objections we have made against the vulgar Chymical Doctrine may as I lately intimated be applied by a little variation to this and therefore I shall need but to touch upon the main things that keep me from acquiescing in this Hypothesis CHAP. II. AND first it seems precarious to affirm that in all bodies or even in all the sensible parts of mixts Acid and Alcalizate parts are found there not having been that I know any Experimental Induction made of particulars any thing near numerous enough to make out so great an assertion and in divers bodies wherein Experience is vouch'd for the inexistence of these Principles that Inexistence is indeed proved not by direct and clear experience but upon a supposition that such and such effects flow from the operations of the assumed Principles Some Spagyrists when they see Aqua fortis dissolve Filings of Copper conclude from thence that the Acid spirits of the Menstruum meet in the metal with an Alcali upon which they work which is but an unsafe way of arguing since good Spirit of Urin which they take to be a volatile Alcali and which will make a great Conflict with Aqua fortis will as I have elsewhere noted dissolve filings of Copper both readily enough and more genuinly than the Acid liquor is wont to do So when they see the Magistery of Pearl or Coral made by dropping oil of Tartar into the solutions of those bodies made with spirit of Vinegar they ascribe the Precipitation to the fixt Alcali of the Tartar that mortifies the Acidity of the spirit of Vinegar whereas the Precipitation would no less insue if instead of Alcalizat oil of Tartar we imploy that highly acid liquor which they call Oleum Sulphuris per Campanam I think also it may be doubted whether those I reason with are so certain as they suppose that at least when they can manifestly discover an Acid for instance in a body the operation of that body upon another which they judge to abound with an Alcali must be the effect of a Conflict between those two jarring Principles or if I may so call them Duellists For an Acid body may do many things not simply as an acid but on the score of a Texture or modification which endows it with other Qualities as well as Acidity whose being associated with those other Qualities in some cases may be but accidental to the effect to be produced since by one or more of these other Qualities the body may act in cases where Prejudice may make a Chymist consider nothing but Acidity Thus when some Chymists see an acid Menstruum as Aqua fortis spirit of Salt oil of Vitriol c. dissolve Iron they presently ascribe the effect to an Acidity of the liquors whereas well dephlegmed Urinous Spirits which they hold to have a great Antipathy to Acids will as I have tried in some of them readily enough dissolve crude Iron even in the Cold. And on the other side Mercury will not work on the filings of Iron though this be so open a metal that even weak liquors will do it and yet if one should urge that Quicksilver readily dissolves Gold in Amalgamation he may expect to be told according to their Doctrine that Mercury has in it an occult acid by which it performs the solution whereas it seems much more probable that Mercury has Corpuscles of such a shape and size as fit them to insinuate themselves into the Commensurate Pores they meet with in Gold but make them unfit to enter readily the Pores of Iron to which Nature has not made them congruous as on the other side the saline Corpuscles of Aqua fortis will easily find admission into the Pores of Iron but not into those of Gold to which they do not correspond as they do to the others And when a knife whose blade is touched with a Load-stone cuts bread and takes up filings of Iron it does neither of them upon the score of Alcali and Acidum but the one upon the visible shape and the stiffness of the blade and the other upon the latent Contrivance or change of Texture produced by the operation of the Load-stone in the particles that compose the Steel This may perhaps be farther illustrated by adding that when blew Vitriol being beaten and finely searced makes a white pouder that whiteness is a quality which the pouder has not as being of a Vitriolate Nature For Rock-Crystal or Venice-glass being finely beaten will have the same operation on the Eye but it proceeds from the transparency of the body and the minuteness multitude and confus'd scituation of the Corpuscles that make up the Pouder And therefore if other bodies be brought by Comminution into parts endow'd with such Mechanical affections as we have named these aggregates will act upon the organs of Sight as white bodies CHAP. III. AND this leads me to another Exception against the Hypothesis of the Duellists which is that the Framers of it seem arbitrarily to have assigned Provinces or Offices to each of their two Principles as the Chymists do to each of their tria prima and the Peripateticks to each of their Four Elements For 't is not enough to Say that an Acid for instance as such performs these things and an Alkali so many others that they divide the Operations and Phaenomena of nature or at least as some more cautious are content to say of mixt bodies between them since Assertions of such great moment ought not to be advanc'd or received without sufficient Proof And perhaps the very distribution of Salts into Acids and Alcalies hath somewhat of arbitrary in it since others may without assuming much more take the freedom to distribute them otherwise there being not only several things wherein Acids and Alcalies agree but also several things wherein Salts of the same denomination widely differ As for Instance some Alkalies according to those I reason with are like salt of Tartar fixt and will endure the violence of the fire others like salt of Urin or Harts-horn are exceedingly fugitive and will be driven up with a scarce sensible degree of Heat some as salt of Tartar will precipitate the solution of Sublimate into an Orange-tawny others as spirit of Blood and Harts-horn precipitate such a solution into a milky substance Oil of Tartar will very slowly operate upon filings of Copper which Spirit of Urin and Harts-horn will readily dissolve in the Fire And among Acids themselves the difference is no less if not much greater Some of them will dissolve bodies that others will not as Aqua fortis will dissolve Silver and Mercury but leave Gold untouched or as Aqua Regis though made without Sal Armoniac that dissolves Gold readily will dissolve Mercury but scurvily and Silver not at all And this may happen when the Menstruum that will not dissolve the body is reputed much stronger than that which does as dephlegm'd spirit of Vinegar will dissolve Lead reduc'd to minute parts in the cold
which is an effect that Chymists are not wont to expect from Spirit of Salt Nay which is more one Acid will precipitate what another has dissolved and contrarily as spirit of Salt will precipitate Silver out of spirit of Nitre And I found oil of Vitriol to precipitate bodies of divers kinds Minerals and others out of some acid Menstruums particularly spirit of Vinegar To this might be added the Properties peculiar to some particular Acids as that Spirit of Nitre or Aqua fortis will dissolve Camphire into an Oil and coagulate common oil into a consistent and brittle substance like Tallow and though it will both corrode Silver Copper Lead and Mercury and keep them dissolved it will quickly let fall almost the whole body of Tin very soon after it has corroded as much as it can of it By all which and some other like Instances I am induc'd to question whether the Acidum and Alkali we are speaking of have the simplicity that Philosophy requires in Principles and shall be kept from wondering if others shall think it as free for them to constitute other Principles as 't is for the Learned men I reason with to pitch upon Acidum and Alkali And some perhaps will be bold to say that since the former of those Principles comprehend such a number of bodies that are many of them very differing and some of them directly contrary in their operations it seems a slight and not Philosophical Account of their Nature to define an Acid by its Hostility to an Alcali which they will say is almost as if one should define a Man by saying that he is an Animal that is at enmity with the Serpent or a Lyon that he is a fourfooted beast that flies from a Crowing Cock. CHAP. IV. BUT although one of the chiefest Conditions that Philosophers may justly require in Principles is that being to explain other things they should be very clear themselves yet I do not much wonder that the Definitions given us of Acidum and Alcali should be but unaccurate and superficial since I find not that they have themselves any clear and determinate Notion or sure marks whereby to know them distinctly without which Chymists will scarce be able to form clear and setled Notions of them For to infer as is usual that because a body dissolves another which is dissoluble by this or that known acid the Solvent must also be acid or to conclude that if a body precipitates a dissolved metal out of a confessedly acid Menstruum the Precipitant must be an Alcali to argue thus I say 't is unsecure since not to repeat what I said lately of Copper I found that filings of Spelter will be dissolved as well by some Alcalies as spirit of Sal Armoniac as by Acids And bodies may be precipitated out of acid Menstruums both by other Acids and by liquors where there appears not the least Alcali As I have found that a solution of Tin-glass made in Aqua fortis would be precipitated both by Spirit of Salt and by common or rain water And as for the other grand way that Chymists employ to distinguish Acids and Alcalies namely by the Heat Commotion and bubbles that are excited upon their being put together that may be no such certain sign as they presume they having indeed a dependance upon particular Contextures and other Mechanical affections that Chymists are not wont to take any notice of For almost any thing that is fitted variously and vehemently to agitate the minute parts of a body will produce Heat in it and so though water be neither an Acid nor an Alcalizate liquor yet it would quickly grow very hot not only with the highly acid Oil of Vitriol but as I have more than once purposely tried and found with the fiery Alcalizat Salt of Tartar And 't is to be noted that neither in the one nor the other of these Incalescent mixtures there is produced any such visible or audible conflict as according to the Doctrine of the Chymists I reason with one would expect And as for the production of bubbles especially if accompanied with a hissing noise neither is that such a certain sign as Chymists imagine For the production of bubbles is not a necessary effect or concomitant of Heat excited by Conflicts but depends very much upon the peculiar Disposition of Bodies put together to extricate produce or intercept particles of Air or Steams for the time equivalent to them and therefore as Oil of Vitriol mixt in a due proportion with fair water may be brought to make the water too hot to be held in ones hand without exciting bubbles so I have found by trials purposely made that Alcalizat Spirit of Urine drawn from some kinds of Quick-lime being mixt with Oil of Vitriol moderately strong would produce an intense Heat whilest it produced either no manifest bubbles at all or scarce any though the Urinous Spirit was strong and in other Trials operated like an Alcali and although also with Spirit of Urin made per se the common way the oil of Vitriol will produce a great hissing and a multitude of conspicuous bubbles On the other side I have sometimes though not so constantly found that some Acid Spirits especially that of Verdigrease made per se would when poured upon Salt of Tartar make a Conflict with it and produce a copious froth though we observed it not to be accompanied with any manifest Heat And I elsewhere mention two bodies upon whose putting together numerous bubbles would for a long time and not without noise be generated and succeed one another though I could perceive no Heat at all to accompany this Tumult As for the Tast which by many is made a great Touchstone whereby to know Acids and Alcalies I consider that there is a multitude of mixt bodies wherein we can so little discern by the Tast which of the Principles is Predominant that this Sense would not oblige one to suspect much less to conclude there were one grain of either of them to be found there such bodies are Diamonds and Rubies and most Gems besides many ignobler Stones and Gold and Silver and Mercury and I know not how many other bodies On the other side there are bodies that abound with Acid or Alcalizat Salts which either have no Tast or a quite differing one from that of the Chymical Principle As though Venice-glass be in great part composed of a fixt Alcali yet to the Tongue it is insipid and Crystalls of Lune and of Lead made with Aqua fortis and containing great store of the Acid particles of the Menstruum have nothing of Acidity in the mouth the latter having a saccharine sweetness and the former an extream bitterness And even in Vegetable substances that have a manifest Tast 't is not so easie to know by that whether it be the Acid or the Alcalizat Principle that is predominant in them as in the Essential oils of Spices and other Vegetables And in
undissolved powder at the bottom and yet if before any Liquor be employed the Sulphur be gently melted and then the Alkali of Tartar be by degrees put to it and incorporated with it as there will result a new Texture discoverable to the eye by the new colour of the Composition so there will emerge a disposition that was not before in either of the Ingredients to be dissolved by Spirit of Wine insomuch that though the mixture be kept till it be quite cold or long after too provided it be carefully secur'd from the access of the air the Spirit of Wine being put to it and shaken with it will if you have gone to work aright acquire a yellow Tincture in a minute of an hour and perhaps in less than half a quarter of an hour a red one being richly impregnated with sulphureous Particles discoverable by the Smell Taste and divers Operations EXPER. II. 'T Is known to several Chymists that Spirit of Salt does not dissolve crude Mercury in the cold and I remember I kept them for a considerable time in no contemptible heat without finding any Solution following But I suppose many of them will be gratified by an Experiment once mention'd to me by an Ingenious German Gentleman namely That if Mercury be precipitated per se that is reduc'd to a red powder without additament by the meer operation of the fire the Texture will be so chang'd that the above-mention'd Spirit will readily dissolve it for I found it upon Trial to do so nay sometimes so readily that I scarce remember that I ever saw any Menstruum so nimbly dissolve any Metalline body whatsoever EXPER. III. THe former Experiment is the more remarkable because that though Oyl of Vitriol will in a good heat corrode Quicksilver as we have already related in the first Section yet I remember I kept a Precipitate per se for divers hours in a considerable degree of Heat without finding it to be dissolved or corroded by the Menstruum And yet having for trials sake put another parcel of the same Mercurial powder into some Aqua fortis or Spirit of Nitre there insued a speedy Dissolution even in the cold And that this Disposition to be dissolved by Spirit of Salt that Mercury acquires by being turned into Precipitate per se that is by being calcin'd is not meerly the effect of the operation of the fire upon it but of some change of Texture produced by that Operation may be probably argued from hence that whereas Spirit of Salt is a very proper Menstruum as I have often tried for the dissolving of Iron or Steel yet when that Metal is reduced by the action of the fire especially if a kind of Vitrification and an irroration with distill'd Vinegar have preceded to Crocus Martis though it be thereby brought to a very fine powder yet I found not that as Spirit of Salt will readily and with heat and noise dissolve Filings of Mars so it would have the same or any thing near such an Operation upon the Crocus but rather after a good while it would leave in the bottom of the Glass a considerable if not the greatest part of it scarce if at all sensibly alter'd And the Menstruum seem'd rather to have extracted a Tincture than made an ordinary Solution since the colour of it was a high yellow or reddish whereas Mars dissolved in Spirit of Salt affords a green Solution Whether by repeated Operations with fresh Menstruum further Dissolutions might in time be made I had not occasion to try and it may suffice for our present purpose that Mars by the operation of the fire did evidently acquire not as Mercury had done a manifest facility but on the contrary a great indisposition to be dissolved by Spirit of Salt To second this Experiment we vary'd it by employing instead of Spirit of Salt strong Oyl of Vitriol which being pour'd on a little Crocus Martis made per se did not as that Menstruum is wont to do upon Filings of crude Mars readily and manifestly fall upon the powder with froth and noise but on the contrary rested for divers hours calmly upon it without so much as producing with it any sensible warmth EXPER. IV. IT agrees very well with our Doctrine about the dependance of the Corrosibility of Bodies upon their Texture that from divers Bodies whilst they are in conjunction with others there result masses and those homogeneous as to sense that are easily dissoluble in Liquors in which a great part of the matter if it were separated from the rest would not be at all dissolved Thus we see that common Vitriol is easily dissolved in meer water whereas if it be skilfully calcin'd it will yield sometimes near half its first weight of insipid Colcothar which not onely is not soluble in water but which neither Aqua Fortis no Aqua Regis though sometimes they will colour themselves upon it are able as far as I have tried to make Solutions of We see likewise that simple water will being boil'd for a competent time with Harts-horn dissolve it and make a Jelly of it And yet when we have taken Harts-horn throughly calcin'd to whiteness not onely we found that common water was no longer a fit Solvent for it but we observed that when we put Oyl of Vitriol it self upon it a good part of the white powder was even by that Corrosive Menstruum left undissolved EXPER. V. IN the Fifteenth of the foregoing Experiments I refer to a way of making the Flower or Powder of common Sulphur become easily dissoluble which otherwise 't is far from being in highly rectified Spirit of Wine Wherefore I shall now adde that 't is quickly perform'd by gently melting the Sulphur and incorporating with it by degrees an equal or a greater weight of sinely powder'd Salt of Tartar or of fixt Nitre For if the mixture be put warm into a Mortar that is so too and as soon as 't is reduc'd to powder be put into a Glass and well shaken with pure Spirit of Wine it will as perhaps I may have elsewhere observed in a few minutes acquire a yellow colour which afterwards will grow deeper and manifest it self by the smell and effects to be a real Solution of Sulphur and yet this Solubleness in Spirit of Wine seems procur'd by the change of Texture resulting from the Commixtion of meer Salt of Tartar which Chymists know to their trouble to be it self a body almost as difficult as Sulphur to be dissolved in phlegmless Spirit of Wine unless the Constitution of it be first alter'd by some convenient additament Which last words I adde because though Spirit of Verdigrease be a Menstruum that uses to come off in Distillation much more intirely than other acid Menstruums from the bodies it has dissolved yet it will serve well for an additament to open as the Chymists speak the body of the Salt of Tartar For this purpose I employ Spirit of Verdigrease not made
as will not be onely very sensible to his hand that holds the Glass whilst the Dissolution is making but will very manifestly discover it self by its Operation upon a Thermoscope Nay I have more than once by wetting the outside of the Glass where the dissolution was making and nimbly stirring the Mixture turn'd that externally adhering water into real Ice that was scrap'd off with a knife in less than a minute of an hour And this thus generated Cold continued considerably intense whilst the action of dissolution lasted but afterwards by degrees abated and within a very few hours ceas'd The particular Phaenomena I have noted in the Experiment and the practical uses that may be made of it I reserve for another place the knowledge of them being not necessary in this where what I have already related may suffice for my present Argument And to shew that not onely a far more intense degree of Cold may emerge in this Mixture than was to be found in either of the Ingredients before they were mingled but a considerable Coldness may be begun to be produc'd between Bodies that were neither of them actually Cold before they were put together I will subjoin a Transcript of what I find to this purpose among my Adversaria EXPER. II. I Remember that once I had a mind to try Whether the Coldness produced upon the Solution of beaten Sal Armoniac in water might not be more probably referr'd to some change of Texture or Motion resulting from the action of the Liquor upon the Salt than to any Infrigidation of the water made by the suddain dispersion of so many Saline grains of powder which by reason of their Solidity may be suspected to be actually more cold than the Water they are put into I therefore provided a Glass full of that Liquor and having brought it to such a Temper that its warmth made the Spirit of Wine in the seal'd Weather-glass manifestly though not nimbly ascend I took out the Thermoscope and laid it in powder'd Sal Armoniac warm'd beforehand so that the tincted Liquor was made to ascend much nimblier by the Salt than just before by the Water and having presently remov'd the Instrument into that Liquor again and poured the somewhat warm Sal Armoniac into the same I found as I imagin'd that within a space of time which I guess'd to be about half a minute or less the Spirit of Wine began hastily to subside and within a few minutes fell above a whole division and a quarter below the mark at which it stood in the water before that Liquor or the Salt were warm'd Nor did the Spirit in a great while reascend to the height which it had when the water was cold The same Experiment being at another time reiterated was tried with the like success which second may therefore serve for a Confirmation of the first EXPER. III. HAving a mind likewise to shew some Ingenious men how much the production of Heat and Cold depends upon Texture and other Mechanical Affections I thought fit to make again a Sal Armoniac by a way I formerly publish'd that I might be sure to know what Ingredients I employ'd and shew their effects as well before conjunction as after it I took then Spirit of Salt and Spirit of fermented or rather putrified Urine and having put a seal'd Weather-glass into an open Vessel where one of them was pour'd in I put the other by degrees to it and observ'd that as upon their mingling they made a great noise with many bubbles so in this conflict they lost their former coldness and impell'd up the Spirit of Wine in the seal'd Thermoscope Then slowly evaporating the superfluous moisture I obtained a fine sort of Sal Armoniac for the most part figur'd not unlike the other when being dissolv'd and filtrated it is warily coagulated This new Salt being gently dry'd I put into a wide Glass of water wherein I had before plac'd a seal'd Weather-glass that the included Spirit might acquire the temper of the ambient Liquor and having stirr'd this Salt in the water though I took it then off the mantle-tree of a Chimney that had had fire in it divers hours before it did as I expected make the tincted Spirit hastily subside and fall considerably low EXPER. IV. SInce if two bodies upon their mixture acquire a greater degree of Cold than either of them had before there is a production of this additional degree of that Quality it will be proper to add on this occasion the ensuing Experiment We took a competent quantity of acid spirit distill'd from Roch-allom that though rectifi'd was but weak which in the spirit of that salt is not strange Of this we put into a wide mouth'd Glass that was not great more than was sufficient to cover the globulous part of a good seal'd Thermoscope and then suffering the instrument to stay a pretty while in the liquor that the Spirit of wine might be cool'd as much as the ambient was we put in little by little some volatile salt sublimed from Sal Armoniac and a fixt Alcali and notwithstanding the very numerous but not great bubbles and the noise and froath that were produced as is usual upon the reaction of Acids and Alcalys the tincted spirit in the Weather-glass after having continued a good while at a stand began a little to descend and continued though but very slowly to do so till the spirit of Allom was glutted with the volatile salt and this descent of the tincted liquor in the Instrument being measur'd appear'd to be about an inch for it manifestly exceeded seven eighths By comparing this Experiment with the first part of the foregoing we may gather that when Volatile and Urinous Salts or Spirits for the saline particles appear sometimes in a dry and sometimes in a liquid form tumultuate upon their being mixt with Acids neither the Heat nor the Cold that ensues is produc'd by a Conflict with the Acids precisely as it is Acid since we have seen that an urinous spirit produc'd an actual Heat with spirit of Salt and the distill'd Salt of Sal Armoniac which is also Urinous with the acid spirit of Roch-Allom produces not a true effervescence but a manifest Coldness As the same Salt also did in a Trial of another sort which was this EXPER. V. WE took one part of Oyl of Vitriol and shaking it into twelve parts of water we made a mixture that at first was sensibly warm then suffering this to cool we put a sufficient quantity of it into a wide mouth'd glass and then we put a good Thermoscope Hermetically seal'd above whose Ball the compounded liquor reached a pretty way After some time had been allowed that the liquor in the Thermometer might acquire the temper of the ambient we put in by degrees as much volatile Salt of Sal Armoniac as would serve to satiate the acid spirits of the mixture for though these two made a notable conflict with
the spittle that usually moistens the tongue their smalness may give them great access to the pores of that organ and the sharpness of their sides and points may fit them to stab and cut and perhaps sear the nervous and membranous parts of the organ of Tast and that variously according to the grand diversities as to shape and bulk of the saporifick particles themselves And this being granted it seemed further conceivable that when the Alkalizate and Acid particles come to be put together in the fluid mixture wherein they swam many of them might after a multitude of various justlings and occursions meet with one another so luckily and opportunely as to recompose little prisms or convene into other bodies almost like those that made up the Crystals of Nitre before 't was exposed to the fire To illustrate which we may conceive that though a prism of iron may be so shaped that it will be wholly unfit to pierce the skin yet it may be so cut by transverse planes reaching to the opposite bases or ends as to afford wedges which by the sharpness of their edges may be fit both to cleave wood and cut the skin and these wedges being again put together after a requisite manner may recompose a prism whose extreams shall be too blunt to be fit for the former use This may be also illustrated by the breaking of a dry stick circularly cut off at the ends which though it is unapt whilst intire and of that bulk to prick the hand yet if it be violently broken the ragged ends of it and the splinters may prove stiff slender and sharp enough to pierce and run into the hand To which divers other such Mechanical Illustrations might be added But since I fear you think as well as I the main conjecture may not be worthy any farther prosecution I shall not insist any longer on it And because the historical part of these Experiments was for the main delivered by me already in the Essay about the Analysis and Redintegration of Nitre I shall now proceed to other Trials EXPER. III. Of two Bodies the one extreamly bitter and the other exceeding salt to make an insipid mixture TO make this Experiment we must very warily pour upon Crystals made of Silver dissolved in good Aqua fortis or Spirit of Nitre strong brine made of common salt and water For the mixture of these two being dried and afterwards brought to fusion in a Crucible and kept a competent while in that state will afford a tough mass the Chymists call Luna Cornea which you may lick divers times and scarce judge it other than insipid nor will it easily be brought to dissolve in much more piercing Menstruums than our spittle as I have elsewhere shewn EXPER. IV. Of two Bodies the one extreamly sweet and the other salter than the strongest Brine to make an insipid mixture THE doing of this requires some skill and much wariness in the Experimenter who to perform it well must take a strong solution of Minium made with an appropriated Menstruum as good Spirit of Vinegar or else Saccharum Saturni it self dissolved in a convenient Vehicle and then must have great care and caution to put to it by degrees a just proportion of strong Spirit of Sal Armoniac or the like Urinous Spirit till the whole be precipitated and if the two former tasts are not sufficiently destroyed in the mixture it may be dried and fluxed as was above directed about Luna Cornea EXPER. V. Of an insipid Body and a sour one to make a Substance more bitter than Gall or Aloes THis is easily performed by dissolving in strong Spirit of Nitre or good Aqua fortis as much pure Silver as the Menstruum will take up for this solution being filtrated has been often esteemed more bitter than so much Gall or Wormwood or any other of those simples that have been famous for that quality And if the superfluous moisture be abstracted you may by coagulation obtain Crystals of Luna that have been judged more strongly bitter than the solution it self And that the corpuscles of these Crystals should leave a far more lasting tast of themselves than the above-mentioned bitter bodies are wont to doe will not seem so marvellous as I remember some that tried have complained if we take notice how deep the particles of these Crystals may pierce into the spungy organs of Tast since if one does but touch the pulp or nail of ones finger first a little wetted with spittle or otherwise with the powder of these Crystals they will so penetrate the skin or nail and stick so fast there that you cannot in a reasonable time wash the stain off of the skin and much less off of the nail but it will continue to appear many hours on the former and many days on the other EXPER. VI. Of an insipid Body and a highly corrosive one to make a Substance as sweet as Sugar THis is easily done by putting upon good Minium purified Aqua fortis or Spirit of Nitre and letting them work upon one another in a gentle heat till the liquour have dissolved its full proportion of the metal For then if the ingredients were good and the operation rightly performed the Menstruum would have a sweetness like that of ordinary Saccharum Saturni But 't was not for nothing that I intimated the ingredients should be also pure and good in their kind for if the Minium be adulterated as often it is or the Spirit of Nitre or Aqua fortis be mingled as it is usual before it be purged with Spirit of common Salt or other unfit ingredients the operation may be successless as I have more than once observed EXPER. VII Of obtaining without addition from the sweetest Bodies Liquours corrosive enough to dissolve Metals IF Sugar be put into a sufficiently capacious Retort and warily distilled for otherwise it will be apt to break the Vessel it will afford among other things a copious red Spirit which being slowly rectified will lose its colour and come over clear The Caput Mortuum of the Sugar which I have more than once had of an odd Contexture may be found either almost or altogether insipid And though the Spirit will be of a very penetrant tast yet it will be very far from any kind of sweetness and though that liquour be thought to be homogeneous and to be one of the Principles of the analized Sugar yet as I have elsewhere shewn I found it to be a mixture of two Spirits with the one of which besides bodies of a less close Texture I dissolved even in the cold crude Copper as was easie to be seen by the deep and lovely colour of the solution And to these sour Spirits afforded by Sugar it self we have restored a kind of Saccharine sweetness by compounding them with the particles of so insipid a body as Minium part of which they will in digestion dissolve A like Spirit to that distilled from Sugar may be
obtained from Honey but in regard of its aptness to swell exceedingly Chymists are not wont to distill it without Sand Brick or some other additament EXPER. VIII To divide a Body bitter in the highest degree into two Substances the one extreamly sour and the other perfectly insipid THis is easily done by putting some fine Crystals of Luna into a good Retort and then distilling them in a Sand-furnace capable of giving them so strong a fire as to drive away all the spirits from the Silver For this remaining behind according to its metalline nature will be insipid and the spirits that are driven away from it will unite in the Receiver into an acid and corrosive Menstruum EXPER. IX To produce variety of Tasts in one insipid Body by associating it with divers Menstruums AS this operation may upon the account I elsewhere mention be serviceable to investigate the figures of the particles of dissolved metals and other bodies so 't is very fit to manifest what we would here have it shew how much Tast may be diversified by and consequently depend upon Texture since a body that has no tast may in conjunction with sapid bodies give them strong tasts all differing from one another and each of them from that which the saporous bodies had before I could propose divers ways of bringing this to trial there being several insipid bodies which I have found this way diversifiable But because I remember not that I have met with any mineral that is dissoluble by near so many saline Menstruums as Zinke I look on that as the most fertile Subject to afford Instances to our present purpose For I have found that it will be dissolved not onely by Aqua fortis Aqua Regis Oil of Vitriol Spirit of Nitre Spirit of Salt and other mineral Menstruums but also by Vegetable Spirits as distilled Vinegar and by Animal ones too as Spirit of Sal Armoniac though the one be Acid and the other Urinous And if the several Solutions which may be made of this mineral by so many differing liquours be compared the number of their differing tasts will suffice to make good the Title of the Experiment EXPER. X. To produce variety of Tasts with one Menstruum by associating it with insipid Bodies THis Proposition a Mathematician would go near to call the Converse of the foregoing and as it may serve as well as that to discover the structure of the minute parts of divers metalline and mineral bodies so it may not onely as well but better than that serve us to illustrate the Corpuscularian Doctrine of Tasts by shewing us that a single and as far as Chymistry teaches us a simple body endowed with a peculiar tast may by being compounded with others each of them insipid of it self produce a considerable number of differing tasts There may be more Instruments than one made use of in this Trial but of those that are known and we may easily obtain the most proper are Spirit of Nitre and good Aqua fortis For that with refined Silver will make a Solution bitter as Gall with Lead 't will be of a Saccharine sweetness with that part of Tin which it will keep dissolved for the greatest 't is wont but to corrode and praecipitate it produces a tast very distant from both the former but not odious with Copper it affords an abominable tast with Mercury and Iron it affords other kinds of bad Tasts Nor are Metals the onely mineral bodies it will work upon For 't will dissolve Tin-glass Antimony Brass to which I could add Emery Zinke and other bodies whereon I have tried it All which together will make up no despicable number of differing Tasts EXPER. XI Of two Liquours the one highly corrosive and the other very pungent and not pleasant to compose a Body of a pleasant and Aromatick Tast. THis Experiment which I elsewhere mention to other purposes does in some regards better suit our present design than most of the foregoing since here the Corrosive Menstruum is neither mortified by fixt nor urinous Salts supposed to be of a contrary nature to it nor yet as 't were tired out nor disarm'd by corroding of metals or other solid bodies The Experiment being somewhat dangerous to make at first in great it may suffice for our present turn to make it in the less quantity as follows Take one ounce of strong Spirit of Nitre or of very good Aqua fortis it self and put to it by little and little which caution if you neglect you may soon repent it and another ounce of such rectified Spirit of Wine as being kindled in a Spoon will flame all away When these two liquours are well mixt and grown cold again you may after some digestion or if hast require without it distill them totally over together to unite them exquisitly into one liquour in which if the operation have been well performed the corrosive particles of the Salts will not onely loose all their cutting acidity wherewith they wounded the palat but by their new composition with the Vinous Spirits the liquour acquires a Vinous tast that is not onely not acid or offensive but very pleasing as if it belonged to some new or unknown Spice EXPER. XII To imitate by Art and sometimes even in Minerals the peculiar Tasts of natural Bodies and even Vegetables THis is not a fit place to declare in what sense I do or do not admit of Souls in Vegetables nor what I allow or deny to the Seminal or Plastick principle ascribed to Plants But perhaps it will not be erroneous to conceive that whatever be the Agent in reference to those Tasts that are said to be specifick to this or that Plant that on whose immediate account it is or becomes of this or that nature is a complication of Mechanical Affections as shape size c. in the particles of that matter which is said to be endowed with such a specifick tast To illustrate this I thought it expedient to endeavour to imitate the tast of some Natural bodies by Artificial Compositions or Preparations but found it not easie beforehand to be assured of the success of such Trials And therefore I shall content my self here to mention three or four Instances that except the first are rather Observations than such Experiments as we are speaking of I remember then that making some Trials to alter the sensible Qualities of Smell Tast c. of Oil of Vitriol and Spirit of Wine I obtained from them among other things that suited with my design a certain Liquour which though at first pleasant would at a certain nick of time make one that had it in his mouth think it had been imbued with Garlick And this brings into my mind that a skilful person famous for making good Sider coming one day to advise with me what he should doe to heighten the tast of it and make it keep the longer complained to me that having among other trials put into a good Vessel
the gross Empereumatical Oils of Woods and even in high Rectified Spirit of Wine which therefore some will have to be an Alcalizat liquor and others list it among Acids though I did not find it neither to be destroyed or much altered by being put upon Coral or salt of Tartar as would happen to an acid Menstruum nor yet by being digested with and distilled from sea Salt as might be probably expected from an Alcalizat one A and among those very bodies which their Tasts perswade Chymists to reckon amongst Acids one may according to what I formerly noted observe so great a difference and variety of relishes that perhaps without being too severe I may say that if I were to allow Acids to be One Principle it should be only in some such Metaphysical sense as that wherein Air is said to be One Body though it consist of the associated effluviums of a multitude of Corpuscles of very differing Natures that agree in very little save in their being minute enough to concur to the Composition of a fluid aggregate consisting of flying parts But having dwelt longer than I intended on One Objection 't is time that I proceed to those that remain CHAP. V. ANother particular I am unsatisfied with in the Hypothesis of Alcali and Acidum is that 't is in divers cases either needless or useless to explain the Phaenomena of Qualities there being several of these produced destroyed or altered where there does not appear any accession recess or change of either of those two Principles as when fluid water by hard beating is turn'd into consistent froth and when transparent red Coral is barely by being beaten and sifted finely changed into a white and opacous powder and as when a very flexible piece of fine silver being hammer'd is brought to have a brisk spring and after a while will instead of continuing malleable crack or cleave under the hammer and as when to dispatch and omit other instances a sufficiently thin leaf of Gold held between the Light and the Eye appears green Another thing of kin to the former that I like not in the Doctrine of Acidum and Alcali is that though the Patrons of it whilest they would seem to constitute but two Principles are fain as I lately intimated to make I know not how many differing sorts of Acids besides some variety of Alcalies yet their Principles are too few and narrow to afford any satisfactory explication of the Phaenomena For I fear 't will be very difficult for them to give a Rational Account of Gravity Springiness Light and Emphatical Colours Sounds and some other Qualities that are wont to be called manifest and much more of several that are confest to be occult as Electricity and Magnetism in which last I see not how the affirming that there is in the Magnet an Acid and an Alcali and that these two are of contrary Natures will help to explain how a Load-stone does as they speak attract the same end of a poised needle with one of its Poles which 't will drive away with the other and determine that needle when freely placed to point North and South and enable it to communicate by its bare touch the same Properties and abundance of other strange ones to another piece of Steel But I forbear to alledge particular Examples referrable to the several Qualities above-mentioned whether manifest or hidden because that in great part is already done in our Notes about particular Qualities in which 't will appear how little able the employing of Alcali and Acidum will be to afford us an account of many things And though I enlarge not here on this objection yet I take it to be of that importance that though there were no other this were enough to shew that the Hypothesis that is liable to it is Insufficient for the explication of Qualities and therefore 't will not I presume be thought strange that I add that as for those that would extend this narrow Chymical Doctrine to the whole object of Natural Philosophy they must do more than I expect they will be able before they can make me their Proselyte there being a multitude of Phaenomena in nature divers whereof I elsewhere take notice of in reference to the Chymists Philosophy in which what Acidum and Alcali have to do I confess I do not understand CHAP. VI. THE last thing which comprizes several others that seems to me a defect in the Doctrine of Alcali and Acidum is that divers if not most of those very things that are pretended to be explicated by them are not satisfactorily explicated some things being taken into the explications that are either not fundamental enough or not clearly intelligible or are chargeable with both those Imperfections And first I am dissatisfied with the very fundamental Notion of this Doctrine namely a supposed Hostility between the tribe of Acids and that of Alkalies accompanied if you will have it so with a friendship or sympathy with bodies belonging to the same tribe or Family For I look upon Amity and Enmity as Affections of Intelligent Beings and I have not yet found it explained by any how those Appetites can be placed in Bodies Inanimate and devoid of knowledge or of so much as Sense And I elsewhere endeavour to shew that what is called Sympathy and Antipathy between such bodies does in great part depend upon the actings of our own Intellect which supposing in every body an innate appetite to preserve it self both in a defensive and an offensive way inclines us to conclude that that body which though designlesly destroys or impairs the state or texture of another body has an Enmity to it though perhaps a slight Mechanical change may make bodys that seem extreamly hostile seem to agree very well and cooperate to the production of the same effects As if the acid spirit of Salt and the volatile Alkali as they will have it that is commonly called Spirit of Urine be put together they will after a short though fierce conflict upon a new contexture unite together into a Salt little if at all differing from Sal Armoniac in which the two reconciled Principles will amicably join in cooling of water dissolving some metalline bodys and producing divers other effects And so if upon a strong solution of Salt of Pot-ashes or of Salt of Tartar good Spirit of Nitre be dropt in a due proportion after the Heat and Tumult and Ebullition are over the Acid and the Alkalizat Salts will convene into such a Concretion as Salt-peter which is taken to be a natural body either homogeneous or at least consisting of parts that agree very friendly together and conspire to constitute the particular kind of Salt that Chymists call Nitre But the Sympathy and Antipathy that is said to be betwixt Inanimate bodys I elsewhere more particularly consider and therefore I shall now add in the second place That the Explications made of Phaenomena according to the Doctrine of Alcali and
Phaenomena where it will not take place and partly because even in those instances wherein 't is thought most applicable the effect seems to depend upon Mechanical Principles EXPER. XII ANd first 't will be difficult to shew what Consanguinity there is between Sal Gem and. Antimony and Iron and Zinke and Bread and Camphire and Lapis Calaminaris and flesh of divers kinds and Oistershels and Harts-horn and Chalk and Quick-lime some of which beong to the Vegetable some to the Mineral and some to the Animal Kingdom and yet all of them and divers others as I have tried may even without the assistance of external Heat be dissolved or corroded by one single Mineral Menstruum Oyl of Vitriol And which is not to be neglected on this occasion some of them may be bodies supposed by Chymists to have an Antipathy to each other in point of Corrosion or Dissolution EXPER. XIII I Observe also that a Dissolution may be made of the same body by Menstruums to which the Chymists attribute as I just now observed they did to some Bodies a mutual Antipathy and which therefore are not like to have a Sympathy with the same third body as I found by trial that both Aqua Fortis and Spirit of Urine upon whose mixture there insues a conflict with a great effervescence will each of them apart readily dissolve crude Zinke and so each of them will the Filings of Copper Not to mention that pure Spirit of Wine and Oyl of Vitriol as great a difference as there is between them in I know not how many respects and as notable a heat as will insue upon their Commixture will each of them dissolve Camphire to which may be added other instances of the like nature As for what is commonly said that Oyls dissolve Sulphur and Saline Menstruums Metals because as they speak Simile simili gaudet I answer That where there is any such similitude it may be very probably ascribed not so much with the Chymists that favour Aristotle to the essential forms of the bodies that are to work on each other nor with the meer Chymists to their Salt or Sulphur or Mercury as such but to the congruity between the pores and figures of the Menstruum and the body dissolved by it and to some other Mechanical Affections of them EXPER. XIV FOr Silver for example not onely will be dissolved by Nitre which they reckon a Salt but be amalgam'd with and consequently dissolved by Quicksilver and also by the operation of Brimstone be easily incorporated with that Mineral which Chymists are wont to account of so oleaginous a nature and insoluble in Aqua Fortis EXPER. XV. ANd as for those Dissolutions that are made with Oylie and inflammable Menstruums of common Sulphur and other inflammable bodies the Dissolution does not make for them so clearly as they imagine For if such Menstruums operate as is alledged upon the account of their being as well as the bodies they work upon of a sulphureous nature whence is it that highly rectified Spirit of Wine which according to them must be of a most Sulphureous nature since being set on fire 't will flame all away without leaving one drop behind it will not unless perhaps after a tedious while dissolve even Flowers of Brimstone which essential as well as express'd Oyls will easily take up as Spirit of Wine it self also will do almost in a trice if as we shall see anon by the help of an Alcali the Texture of the Brimstone be alter'd though the onely thing that is added to the Sulphur being an incombustible substance is nothing near of so sulphureous a nature as the Flowers and need have no Consanguinity upon the score of its Origine with Spirit of Wine as 't is alledged that Salt of Tartar has since I have tried That fixt Nitre employ'd instead of it will do the same EXPER. XVI THe mention of Nitre brings into my mind that the Salt peter being wont to be lookt upon by Chymists as a very inflammable body ought according to them to be of a very sulphureous nature yet we find not that 't is in Chymical Oyls but in water readily dissolved And whereas Chymists tell us that the Solutions of Alcaly's such as Salt of Tartar or of Pot-ashes in common Oyls proceed from the great cognation between them I demand whence it happens that Salt of Tartar will by boiling be dissolved in the exprest Oyl of Almonds or of Olives and be reduc'd with it to a soapy body and that yet with the essential Oyl of Juniper or Aniseeds c. where what they call the Sulphur is made pure and penetrant being freed from the earthy aqueous and feculent parts which Distillation discovers to be in the exprest Oyls you may boil Salt of Tartar twenty times as long without making any Soap of them or perhaps any sensible Solution of the Alkaly And Chymists know how difficult it is and how unsuccessfully 't is wont to be attempted to dissolve pure Salt of Tartar in pure Spirit of Wine by digesting the not peculiarly prepar'd Salt in the cognate Menstruum I will not urge that though the most conspicuous mark of Sulphur be inflammability and is in an eminent degree to be found in Oyl as well as Sulphur yet an Alkaly and water which are neither singly nor united inflammable will dissolve common Sulphur EXPER. XVII BUt to make it probable against the Chymists for I propose it but as an argument ad hominem that the Solution of Sulphur in exprest Oyls depends upon somewhat else besides the abundance of the second Principle in both the bodies I will adde to what I said before an affirmation of divers Chymical Writers themselves who reckon Aqua Regis which is plainly a Saline Menstruum and dissolves Copper Iron Coral c. like Acid Liquors among the Solvents of Sulphur and by that power among other things distinguish it from Aqua Fortis And on the other side if there be a Congruity betwixt an exprest Oyl and another body though it be such as by its easie Dissolubleness in Acid Salts Chymists should pronounce to be of a saline nature an exprest Oyl will readily enough work upon it as I have tried by digesting even crude Copper in Filings with Oyl of sweet Almonds which took up so much of the metal as to be deeply coloured thereby as if it had been a Corrosive Liquor Nay I shall adde that even with Milk as mild a Liquor as 't is I have found by Trial that without the help of fire a kind of Dissolution may though not in few hours be made of crude Copper as appear'd by the greenish blew colour the Filings acquired when they had been well drenched in the Liquor and left for a certain time in the Vessel where the air had very free access to them EXPER. XVIII BEsides the Argument ad hominem newly drawn from Aqua Regia it may be proper enough to urge another of the same
great commotion with hissing and bubbles produced the Copper would not be precipitated because this Urinous spirit will as well as the Salt and much more readily dissolve the same metal and it would be kept dissolved notwithstanding their operation on one another the intervening of which and their action upon the metalline corpuscles may be gathered from hence that the green solution made with spirit of salt alone will by the supervening urinous spirits be changed either into a blewish green or if the proportion of this spirit be very great into a rich blew almost like ultramarine And from these two Experiments we may probably argue that when the Precipitation of a metal c. insues it is not barely on the account of the supposed Antipathy betwixt the Salts but because the causes of that seeming Antipathy do likewise upon a Mechanical account dispose the Corpuscles of the confounded liquors so to cohere as to be too unwieldy for the fluid part CHAP. VI. ANother way whereby the dissolving particles of a Menstruum may be rendred unfit to sustain the dissolved body is to present them another that they can more easily work on A notable Experiment of this you have in the common practice of Refiners who to recover the Silver out of Lace and other such mixtures wherein it abounds use to dissolve it in Aqua fortis and then in the solution leave Copper plates for a whole night or many hours But if you have a mind to see the Experiment without waiting so long you may imploy the way whereby I have often quickly dispatched it As soon then as I have dissolved a convenient quantity which needs not be a great one of Silver in cleansed Aqua fortis I add twenty or twenty five times as much of either distilled water or rain water for though common water will sometimes do well yet it seldome does so well and then into the clear solution I hang by a string a clean piece of Copper which will be presently covered with little shining plates almost like scales of fish which one may easily shake off and make room for more And this may illustrate what we formerly mentioned about the subsiding of metalline corpuscles when they convene in liquors wherein whilst they were dispersed in very minute parts they swam freely For in this operation the little scales of Silver seemed to be purely metalline and there is no saline Precipitant as Salt of Tartar or of Urine imployed to make them subside Upon the same ground Gold and Silver dissolved in their proper Menstruums may be precipitated with running Mercury and if a Solution of blew Vitriol such as the Roman East-Indian or other of the like colours be made in water a clean plate of Steel or Iron being immersed in it will presently be overlaid with a very thin case of Copper-which after a while will grow thick er but does not adhere to the iron so loosely as to be shaken off as the Precipitated silver newly mentioned may be from the Copper-plates whereto it adheres And that in these operations the saline particles may really quit the dissolved body and work upon the Precipitant may appear by the lately mentioned practice of Refiners where the Aqua-fortis that forsakes the particles of the silver falls a working upon the copper-plates imployed about the Precipitation and dissolves so much of them as to acquire the greenish blew colour of a good solution of that metal And the Copper we can easily again without salts obtain by Precipitation out of that liquor with iron and that too remaining dissolved in its place we can precipitate with the tastless powder of another Mineral Besides these two ways of weakning the Menstruum namely by mortifying its saline particles or seducing them to work on other bodies and to forsake those they first dissolved there are some other ways of weakning the Menstruum A Third way of effecting this is by lessening or disturbing the agitation of the solvent And indeed since we find by experience that some liquors when they are heated will either dissolve some bodies they would not dissolve at all when they were cold or dissolve them more powerfully or copiously when hot than cold 't is not unreasonable to suppose that what considerably lessens that agitation of the parts of the Menstruum that is necessary to the keeping the dissolved body in the state of fluidity should occasion the falling of it again to the bottom In slow operations I could give divers examples of the precipitating power of Cold there being divers solutions and particularly that of Amber-greece that I had kept fluid all the Summer which in the Winter would subside And the like may be sometimes observed in far less time in the solutions of Brimstone made in certain oleaginous Menstruums and I have now then had some solutions and particularly one of Benzoin made in spirit of wine that would surprize me with the turbidness which begins the state of Precipitation it would acquire upon a sudden change of the weather towards Cold though it were not in the winter season Another way of weakening the Menstruum and so causing the Precipitation of a body dissolved in it is the diluting or lessening the tenacity of it whether that tenacity proceed from viscosity or the competent number and constipation of the parts Of this we have aninstance in the Magisteries as many Chymists are pleased to call them of Jalap Benzion and of divers others Resinous and Gummous bodies dissolved in spirit of wine For by the affusion of common water the Menstruum being too much diluted is not able to keep those particles in the state of fluidity but must suffer them to subside as they usually do in the form of white powder or as it may happen sometimes make some parts emerge Examples also of this kind are afforded us by the common preparations of Mercurius Vitae For though in oil of Antimony made by the Rectification of the butter the saline particles are so numerous and keep so close to one another that they are able to sustain the Antimonial Corpuscles they carried over with them in Distillation and keep them together with themselves in the form of a liquor yet when by the copious affusion of the water those sustaining particles are separated and removed to a distance from each other the Antimonial Corpuscles and the Mercurial if any such there were being of a ponderous nature will easily subside into that Emetic powder which when well washed the Chymists flatteringly enough call Mercurius Vitae But here I must interpose an advertisement which will help to shew us how much Precipitations depend upon the Mechanical contextures of bodies For though not only in the newly recited examples but in divers others the affusion of water by diluting the salts and weakenning the Menstruum makes the metall or other dissolved body fall precipitately to the bottom yet if the saline particles of the solvent and those of the body
be fitted for so strict an union that the Corpuscles resulting from their Coalitions will not so easily be separated by the particles of water as suffer themselves to be carried up and down with them whether because of the minuteness of these compounded Corpuscles or because of some congruity betwixt them and those of the water they will not be precipitated out of the weakened solution but still continue a part of it as I have tryed partly with some solution of Silver and Gold made in acid Menstruums but much more satisfactorily in solutions of Copper made in the urinous spirit of Sal Armoniac For though that blew solution were diluted with many thousand times as much distilled water as the dissolved metal weighed yet its swimming Corpuscles did by their colour manifestly appear to be dispersed through the whole liquor CHAP. VII BUT to prosecute our former discourse which we broke off after the mention of Mercurius Vitae 't will now be seasonable to add that we have made divers other Precipitations by the bare affusion of water out of solutions and sometimes out of distilled liquors which for brevity sake I here omit that I may hasten to the last way I shall now stay to mention Another way then whereby Precipitations of bodies may be produced by debilitating the Menstruum they swim in is by lessening the proportion of the Solvent to the Solutum without any evaporation of the liquor These last words I add because that when there is an obstruction or any other expulsion of the Menstruum by heat if it be total 't is called Exsiccation as when dry salt of Tartar is obtained from the filtrated Lixivium of the calcined Tartar and though the evaporation be not total yet the effects of it are not wont to be reckoned amongst Precipitations And although the way I am about to propose if it be attentively considered has much affinity with the foregoing and the Phaenomena may perhaps in some sort be reduced to them yet the instances that I shall name having not that I know been thought of by others and being such as every one would not deduce from what I have been mentioning I shall add a word of the inducements I had to make the tryals as well as of the success of them Considering then that Water will not dissolve Salts indefinitely but when it has received its due proportion 't will then dissolve no more but if they be put into it let them fall to the ground and continue undissolved and that if when water is satiated any of the liquor be evaporated or otherwise wasted it will in proportion let fall the salt it had already taken up I concluded that if I could mingle with water any liquor with which its particles would more readily associate than with those of Salt the depriving the solution of so many of its aqueous particles would be equivalent to the evaporation of as much water or thereabouts as they by being united could compose Wherefore making a lixivium of distilled water or clean rain-water and of Salt of Tartar so strong that if a grain more were cast in it it would lie undissolved at the bottom I put a quantity of this fiery Lixivium into a slender cylindrical vessel till it had therein reached such a height as I thought fit then taking as much as I thought sufficient of strong spirit of wine that would burn every drop away that so it might have no flegm nor water of its own I poured this upon the saline solution and shaking the liquors pretty well together to bring them to mix as well as I could I laid the tube in a quiet place and afterwards found as I expected that there was a pretty quantity of white salt of Tartar fallen to the bottom of the vessel which salt had been meerly forsaken by the aqueous particles that sustained it before but forsook it to pass into the spirit of wine wherewith they were more disposed to associate themselves which I concluded because having before I poured on this last named liquor made a mark on the glass to shew how far the lixivium reached I found what I looked for that after the Precipitation the Lixivium that remained yet strong enough to continue unmixed with the incumbent spirit had its surface not where the mark shewed it had been before but a considerable distance beneath it the spirit of wine having gained in extent what it lost in strength by receiving so many aqueous particles into it I chose to make this tryal rather with a Lixivium of Salt of Tartar than with oyl of Tartar per Deliquium because in this last named liquor the aqueous and saline particles are more closely combined and therefore more difficult to be separated than I thought they would be in a Lixivium hastily made though very strong And though by much agitation I have sometimes obtained some salt of Tartar from the above-mentioned oil yet the experiment succeeded nothing near so well with that liquor as with a Lixivium I made also the like tryal with exceedingly dephlegmed spirit of wine and as strong a Brine as I could make of common salt dissolved without heat in common water and I thereby obtained no despicable proportion of finely figured salt that was let fall to the bottom But this experiment to be succesful requires greater care in him that makes it than the former needs To confirm and somewhat to vary this way of Precipitation I shall add that having made a clear solution of choice Gum Arabic in common water and poured upon it a little high rectified spirit of wine on this occasion there was also made and that in a trice a copious precipitation of a light and purely white substance not unpleasant to behold And for further Confirmation I dissolved a full proportion of Myrrhe in fair water and into the filtrated solution which was transparent but of a high brown colour I dropt a large proportion which Circumstance is not to be omitted of carefully dephlegm'd spirit of wine which according to expectation made a copious Precipitate of the Gum. And these instances I the rather set down in this place because they seem to show that simple water is a real Menstruum which may have its dissolving and sustaining virtue weakened by the accession of Liquors that are not doubted to be much stronger than it By specifying the hitherto mentioned wayes whereby Precipitations may be Mechanically performed and accounted for I would by no means be thought to deny that there may be some omitted here which either others that shall consider the matter with more attention or I my self if I shall have leisure to do it may think on For I propose these but as the chief that occurr to my present thoughts and I forbear to add more instances to exemplifie them because I would not injure some of my other papers that have a greater right to those Instances Only this I shall note in general that the Doctrine
small a quantity of Poyson some small Concretions or Coagulations made of the minute particles of the bloud into little clots less agile and more unwieldy than they were when they moved separately which may be illustrated by the little Curdlings that may be made of the parts of Milk by a very small proportion of Runnet or some acid liquor and the little coagulations made of the Spirit of Wine by that of Urine Nor will I now enquire whether besides the retardment of the motion of the bloud some poysons and other analogous Agents may not give the motion of it a new modification as if some Corpuscles that usually are more whirl'd or brandish'd be put into a more direct Motion that may give it a peculiar kind of grating or other action upon the nervous and fibrous parts of the body These I say and other suspicious that have sometimes come into my thoughts I must not stay to examine but shall now rather offer to Consideration Whether since some parts of the humane body are very differing from others in their structure and internal Constitution and since also some Agents may abound in Corpuscles of differing shapes bulks and motions the same Medicine may not in reference to the same humane body be potentially cold or potentially hot according as 't is applied or perhaps may upon one or both of the accounts newly mentioned be cold in reference to one part of the body and hot in reference to the other And these effects need not be always ascrib'd to the meer and immediate action of the Corpuscles of the Medicine but sometimes to the new Quality they acquire in their Passage by associating themselves with the bloud or other fluids of the body or to the expulsion of some calorific or frigorific Corpuscles or to the Disposition they give the part on which they operate to be more or less permeated and agitated than before by some subtile aethereal matter or other Efficients of Heat or Cold. Some of these Conjectures about the Relative Nature of Potentially cold bodies may be either confirmed or illustrated by such Instances as these that Spirit of Wine being inwardly taken is potentially very hot and yet being outwardly applied to some Burns and some hot Tumours does notably abate the Heat of the inflamed parts though the same Spirit applied even outwardly to a tender eye will cause a great and dolorous agitation in it And Camphire which in the Dose of less than a half or perhaps a quarter of a Scruple has been observed to diffuse a Heat through the body is with success externally applied by Physicians and Chirurgeons in refrigerating Medicines But I leave the further Inquiry into the Operations of Medicines to Physicians who may possibly by what has been said be assisted to compose the differences between some famous Writers about the temperament of some Medicines as Mercury Camphire c. which some will have to be cold and others maintain to be hot and shall onely offer by way of confirming in general that Potential Coldness is onely a Relative Quality a few Particulars the first whereof is afforded by comparing together the VI. and the VII Experiment before going which have oceasion'd this Digression about Potential Coldness since by them it seems probable that the same thing may have it in reference to one body and not to another according to the disposition of the body it operates upon or that operates upon it And the Fumes of Lead have been observed sometimes for I have not found the Effect to succeed always to arrest the fluidity of Mercury which change is supposed to be the effect of a Potential Coldness belonging to the Chymists Saturn in reference to fluid Mercury though it have not that operation on any other liquor that we know of And lastly for I would not be too prolix though Nitre and Sal Armoniac be both apart and joyntly Cold in reference to Water and though however Nitre be throughly melted in a Crucible it will not take fire of it self yet if whilst it is in Fusion you shall by degrees cast on it some powder'd Sal Armoniac it will take fire and flash vehemently almost as if Sulphur had been injected But our Excursion has I fear lasted too long and therefore I shall presently re-enter into the way and proceed to set down some Trials about Cold. EXPER. VIII IN the first Experiment we observed that upon the pouring of water upon Sal Armoniac there ensued an intense degree of Cold and we have elsewhere recited that the like effect was produc'd by putting instead of common water Oyl of Vitriol to Sal Armoniac but now to shew further what influence Motion and Texture may have upon such Trials it may not be amiss to adde the following Experiment To twelve ounces of Sal Armoniac we put by degrees an equal weight of water and whilst the Liquor was dissolving the Salt and by that action producing a great Coldness we warily pour'd in twelve ounces also of good Oyl of Vitriol of which new mixture the event was that a notable degree of Heat was quickly produced in the Glass wherein the Ingredients were confounded as unlikely as it seemed that whereas each of the two Liquors is wont with Sal Armoniac to produce an intense Cold both of them acting on it together should produce the contrary Quality But the reason I had to expect the success I met with was this that 't was probable the Heat arising from the mixture of the two Liquors would overpower the Coldness produceable by the operation of either or both of them upon the Salt FINIS EXPER. IX IN most of the Experiments that we have hitherto proposed Cold is wont to be regularly produc'd in a Mechanical way but I shall now adde that in some sort of Trials I found that the Event was varied by unobserv'd Circumstances so that sometimes manifest Coldness would be produced by mixing two Bodies together which at another time would upon their Congress disclose a manifest Heat and sometimes again though more rarely would have but a very faint and remiss degree of either Of this sort of Experiments whose Events I could not confidently undertake for I found to be the dissolution of Salt of Tartar in Spirit of Vinegar and of some other Salts that were not acid in the same Menstruum and even Spirit of Verdigrease made per se though a more potent Menstruum than common Spirit of Vinegar would not constantly produce near such a heat at the beginning of its operation as the greatness of the seeming Effervescence then excited would make one expect as may appear by the following Observation transcrib'd verbatim out of one of my Adversaria Into eight ounces of Spirit of Verdigrease into which we had put a while before a standard-Thermoscope to acquire the like temper with the Liquor we put in a wide-mouthed Glass two ounces of Salt of Tartar as fast as we durst for fear of making
the matter boil over and though there were a great commotion excited by the action and reaction of the Ingredients which was attended with a copious froth and a hissing noise yet 't was a pretty while e're the Glass was sensibly warm on the outside but by that time the salt was all dissolv'd the Liquor in the Thermoscope appear'd to be impell'd up about three inches and an half And yet if my memory do not much deceive me I have found that by mixing Salt of Tartar with another Salt the Texture of the fixt Alkali was so alter'd that upon the affusion of spirit of Verdigrease made without spirit of Vinegar and spirit of Wine though there ensued a great conflict with noise and bubbles yet instead of an Incalescence a considerable degree of Coldness was produced EXPER. X. T Is very probable that further Trials will furnish us with more Instances to shew how the Production of Cold may in some cases be effected varied or hinder'd by Mechanical Circumstances that are easily and usually overlook'd I remember on this occasion that though in the Experiment above recited we observ'd that Oyl of Vitriol and water being first shaken together the volatil salt of Sal Armoniac being afterwards put to them produced a sensible Coldness yet I found that if a little Oyl of Vitriol and of the volatile Salt were first put together though soon after a considerable proportion of water were added there would be produc'd not a Coldness but a manifest degree of Heat which would impell up the liquor in the Thermoscope to the height of some inches And I remember too that though Salt of Tartar will as we shall see e're long grow hot in the water yet having distill'd some Salt of Tartar and Cinaber in a strong fire and put the whole Caput mortuum into distill'd or Rain-water it made indeed a hissing there as if it had been Quick-lime but produced no Heat that I could by feeling perceive I shall adde that not onely as we have seen already some unheeded Circumstances may promote or hinder the artificial Production of Cold by particular Agents but which will seem more strange some unobserv'd and perhaps hardly observable Indisposition in the Patient may promote or hinder the effects of the grand and Catholick Efficients of Cold whatever those be This suspicion I represent as a thing that further experience may possibly countenance because I have sometimes found that the degree of the Operation of Cold has been much varied by latent Circumstances some bodies being more wrought upon and others less than was upon very probable grounds expected And particularly I remember that though Oyl of Vitriol be one of the firiest liquors that is yet known and does perform some of the Operations of fire it self as we shall elsewhere have occasion to shew and will thaw Ice sooner than Spirit of Wine or any other liquor as I have tried yet having put about a pound or more by our estimate of choice rectified Oyl of Vitriol into a strong Glass-Vial proportionable to it we found that except a little that was fluid at the top it was all congeal'd or coagulated into a mass like Ice though the Glass stood in a Laboratory where a fire was constantly kept not far from it and where Oyl of Vitriol very seldom or never has before or since been observ'd to congeal or coagulate so much as in part And the odness of our Phaenomenon was increas'd by this Circumstance that the Mass continued solid a good while after the weather was grown too mild to have such Operations upon Liquors far less indispos'd to lose their fluidity by Cold than even common Oyl of Vitriol is On the other side I remember that about two years ago I expos'd some Oyl of sweet Almonds hermetically seal'd up in a Glass-bubble to observe what Condensation an intense cold could make of it for though Cold expands water it condenses common oyl but the next day I found to my wonder that not onely the oyl remain'd unfrozen by the sharp frost it had been expos'd to but that it had not its transparency troubled though 't is known that oyl will be brought to concrete and turn opacous by a far less degree of Cold than is requisite to freeze water notwithstanding which this liquor which was lodged in a glass so thin that 't was blown at the flame of a Lamp continued fluid and diaphanous in very frosty weather so long till I lost the expectation of seeing it congeal'd or concreted And this brings into my mind that though Camphire be as I formerly noted reckon'd by many potentially cold yet we kept some oyl of it of our making wherein the whole body of the Camphire remain'd being onely by some Nitrous Spirits reduc'd to the form of an Oyl we kept it I say in such intense degrees of Cold that would have easily frozen water without finding it to lose its Transparency or its Fluidity And here I shall put an end to the first Section containing our Notes about Cold the design of which may be not a little promoted by comparing with them the beginning of the ensuing Section For if it be true that as we there shew the nature of Heat consists either onely or chiefly in the local motion of the small parts of a body Mechanically modified by certain conditions of which the principal is the vehemency of the various agitations of those insensible parts and if it be also true as Experience witnesses it to be that when the minute parts of a body are in or arrive at such a state that they are more slowly or faintly agitated than those of our fingers or other organs of feeling we judge them cold These two things laid together seem plainly enough to argue that a Privation or Negation of that Local Motion that is requisite to constitute Heat may suffice for the denominating a body Cold as Coldness is a quality of the Object which as 't is perceiv'd by the mind is also an affection of the Sentient And therefore an Imminution of such a degree of former motion as is necessary to make a body Hot as to sense and which is sufficient to the Production of sensible Coldness may be Mechanically made since Slowness as well as Swiftness being a Mode of Local motion is a Mechanical thing And though its effect which is Coldness seem a Privation or Negation yet the Cause of it may be a positive Agent acting Mechanically by clogging the Agile Calorific Particles or deadning their motion or perverting their determination or by some other intelligible way bringing them to a state of Coldness as to sense I say Coldness as to sense because as 't is a Tactile Quality in the popular acception of it 't is relative to our Organs of Feeling as we see that the same luke-warm water will appear hot and cold to the same mans hands if when both are plung'd into it one of them shall have been newly
enough to produce a sensible Heat especially if we admit that there is such a change made in the Pores as occasions a great increase of this agitation by the ingress and action of some subtile ethereal matter from which alone Monsieur des Cartes ingeniously attempts to derive the Incalescence of Lime and water as well as that of metals dissolved in corrosive Liquors though as to the Phaenomena we have been considering there seems at least to concur a peculiar disposition of body wherein Heat is to be produced to do one or both of these two things namely to retain good store of the igneous Effluvia and to be by their adhesion or some other operation of the fire reduced to such a Texture of its component Particles as to be fit to have them easily penetrated and briskly as well as copiously dissipated by invading water And this Conjecture for I propose it as no other seems favour'd by divers Phaenomena some whereof I shall now annex For here it may be observed that both the dissolved Salt of Tartar lately mentioned and the artificial Liquor that grows hot with the natural reacquires that Disposition to Incalescence upon a bare Constipation or closer Texture of the parts from the superfluous moisture they were drowned in before The Heat that brought them to this Texture having been so gentle that 't is no way likely that the igneous Exhalations could themselves produce such a Heat or at least that they should adhere in such numbers as must be requisite to such an effect unless the Texture of the Salt of Tartar or other body did peculiarly dispose it to detain them since I have found by Trial that Sal Armoniac dissolv'd in water though boiled up with a brisker fire to a dry salt would upon its being again dissolved in water not produce any Heat but a very considerable degree of Cold. I shall adde that though one would expect a great Cognation between the particles of Fire adhering to Quick-Lime and those of high rectified Spirit of Wine which is of so igneous a nature as to be totally inflammable yet I have not found that the affusion of Alkaol of Wine upon Quick-Lime would produce any sensible Incalescence or any visible dissolution or dissipation of the Lime as common water would have done though it seemed to be greedily enough soaked in by the lumps of Lime And I further tried that if on this Lime so drenched I poured cold water there insued no manifest Heat nor did I so much as find the lump swelled and thereby broken till some hours after which seems to argue that the Texture of the Lime was such as to admit the particles of the Spirit of Wine into some of its pores which were either larger or more congruous without admitting it into the most numerous ones whereinto the Liquor must be received to be able suddenly to dissipate the Corpuscles of Lime into their minuter particles into which Corpuscles it seems that the change that the aqueous particles received by associating with the spirituous ones made them far less fit to penetrate and move briskly there than if they had enter'd alone I made also an Experiment that seems to favour our Conjecture by shewing how much the Disposition of Lime to Incalesoence may depend upon an idoneous Texture and the Experiment as I find it registred in one of my Memorials is this EXPER. V. UPon Quick-lime we put in a Retort as much moderately strong Spirit of Wine as would drench it and swim a pretty way above it and then distilling with a gentle fire we drew off some Spirit of Wine much stronger than that which had been put on and then the Phlegm following it the fire was increas'd which brought over a good deal of phlegmatic strengthless Liquor by which one would have thought that the Quick-lime had been slaked but when the remaining matter had been taken out of the Retort and suffer'd to cool it appear'd to have a fiery disposition that it had not before For if any lump of it as big as a Nutmeg or an Almond was cast into the water it would hiss as if a coal of fire had been plunged into the Liquor which was soon thereby sensibly heated Nay having kept divers lumps of this prepared Calx well cover'd from the air for divers weeks to try whether it would retain this property I found as I expected that the Calx operated after the same manner if not more powerfully For sometimes especially when 't was reduced to small pieces it would upon its coming into the water make such a brisk noise as might almost pass for a kind of Explosion These Phaenomena seem to argue that the Disposition that Lime has to grow hot with water depends much on some peculiar Texture since the aqueous parts that one would think capable of quenching all or most of the Atomes of Fire that are supposed to adhere to Quick-lime did not near so much weaken the disposition of it to Incalescence as the accession of the spirituous Corpuscles and their Contexture with those of the Lime increased that igneous Disposition And that there might intervene such an association seems to me the more probable not onely because much of the distill'd Liquor was as phlegmatick as if it had been robb'd of its more active parts but because I have sometimes had Spirit of Wine come over with Quick-lime not in unobserved steams but white fumes To which I shall adde that besides that the Taste and perhaps Odour of the Spirit of Wine is often manifestly changed by a well-made Distillation from Quick-lime I have sometimes found that Liquor to give the Lime a kind of Alcalizat penetrancy not to say fieriness of Taste that was very brisk and remarkable But I will not undertake that every Experimenter nor I my self shall always make trials of this kind with the same success that I had in those above recited in regard that I have found Quick-limes to differ much not onely according to the degree of their Calcination and to their Recentness but also and that especially according to the differing natures of the stones and other bodies calcined Which Observation engages me the more to propose what hath been hitherto deliver'd about Quick-lime as onely Narratives and a Conjecture which I now perceive has detain'd us so long that I am oblig'd to hasten to the remaining Experiments and to be the more succinct in delivering them EXPER. VI. ANd it will be convenient to begin with an instance or two of the Production of Heat wherein there appears not to intervene any thing in the part of the Agent or Patient but Local Motion and the natural Effects of it And as to this sort of Experiments a little attention and reflection may make some familiar Phaenomenon apposite to our present purpose When for example a Smith does hastily hammer a Nall or such like piece of iron the hammer'd metal will grow exceeding hot and yet there appears not
copious diffusion of the parts of one body through those of another whereby both are confusedly tumbled and put into a calorific motion or from this that the parts of the dissolved body come to be every way in great numbers violently scatter'd or from the fierce and confused shocks or justlings of the Corpuscles of the conflicting bodies or masses which may be suppos'd to have the motions of their parts differingly modified according to their respective Natures Or from this that by the plentiful ingress of the Corpuscles of the one into the almost commensurate parts of the other the motion of some etherial matter that was wont before swiftly to permeate the distinct bodies comes to be check'd and disturbed and forced to either brandish or whirl about the parts in a confus'd manner till it have settled it self a free passage through the new mixture almost as the Light does thorow divers troubled liquors and vitrified bodies which at length it makes transparent But without here engaging in a solemn examination of the Hypothesis of Alcali and Acidum and without determining whether any one or more of the newly mention'd Mechanical Causes or whether some other that I have not yet named is to be entitled to the effect it will not be impertinent to propose divers Instances of the Production of Heat by the Operation of one Agent Oyl of Vitriol that it may be consider'd whether it be likely that this single Agent should upon the score of Antipathy or that of its being an Acid Menstruum be able to produce an intense Heat in many bodies of so differing natures as are some of those that we shall have occasion to name And now I proceed to the Experiments themselves Take some ounces of strong Oyl of Vitriol and shaking it with three or four times its weight of common water though both the liquors were cold when they were put together yet their mixture will in a trice grow intensely hot and continue considerably so for a good while In this case it cannot probably be pretended by the Chymists that the Heat arises from the conflict of the Acid and Alcalizate Salts abounding in the two liquors since the common water is suppos'd an elementary body devoid of all salts and at least being an insipid liquor 't will scarce be thought to have Alcali enough to produce by its Reaction so intense a Heat That the Heat emergent upon such a mixture may be very great when the Quantities of the mingled liquors are considerably so may be easily concluded from one of my Memorials wherein I find that no more than two ounces of Oyl of Vitriol being poured but not all at once into four ounces onely of distilled Rain-water made and kept it manifestly warm for a pretty deal above an hour and during no small part of that time kept it so hot that 't was troublesome to be handled EXPER. XIV THe former Experiment brings into my mind one that I mention without teaching it in the History of Cold and it appear'd very surprizing to those that knew not the ground of it For having sometimes merrily propos'd to heat cold liquors with Ice the undertaking seem'd extravagant if not impossible but was easily perform'd by taking out of a bason of cold water wherein divers fragments of Ice were swimming one or two pieces that I perceived were well drenched with the liquor and immersing them suddenly into a wide-mouth'd Glass wherein strong Oyl of Vitriol had been put for this Menstruum presently mingling with the water that adher'd to the ice produc'd in it a brisk heat and that sometimes with a manifest smoke which nimbly dissolved the contiguous parts of Ice and those the next and so the whole Ice being speedily reduced to water and the corrosive Menstruum being by two or three shakes well dispersed through it and mingled with it the whole mixture would grow in a trice so hot that sometimes the Vial that contain'd it was not to be endured in ones hand EXPER. XV. NOtwithstanding the vast difference betwixt common water and high rectified Spirit of Wine whereof men generally take the former for the most contrary body to fire and whereof the Chymists take the later to be but a kind of liquid Sulphur since it may presently be all reduc'd into flame yet as I expected I found upon trial that Oyl of Vitriol being mingled with pure Spirit of Wine would as well grow hot as with common water Nor does this Experiment always require great quantities of the liquors For when I took but one ounce of strong Oyl of Vitriol though I put to it less than half an ounce of choice Spirit of Wine yet those two being lightly shaken together did in a trice conceive so brisk a Heat that they almost fill'd the vial with fumes and made it so hot thar I had unawares like to have burnt my hand with it before I could lay it aside I made the like Trial with the same Corrosive Menstruum and common Aqua vitae bought at a Strong-water-shop by the mixture of which Liquors Heat was produc'd in the Vial that I could not well endure The like success I had in an Experiment wherein Oyl of Vitriol was mixt with common Brandy save that in this the Heat produced seem'd not so intense as in the former Trial which it self afforded not so fierce a Heat as that which was made with rectified Spirit of Wine EXPER. XVI THose Chymists who conceive that all the Incalescencies of bodies upon their being mixt proceed from their antipathy or hostility will not perhaps expect that the parts of the same body either numerically or in specie as the Schools phrase it should and that without manifest conflict grow very hot together And yet having for trials sake put two ounces of Colcothar so strongly calcin'd that it was burnt almost to blackness into a Retort we poured upon it two ounces of strong Oyl of English Vitriol and found that after about a minute of an hour they began to grow so hot that I could not endure to hold my hand to the bottom of the Vessel to which the mixture gave a heat that continued sensible on the outside for between twenty and thirty minutes EXPER. XVII THough I have not observ'd any Liquor to equal Oyl of Vitriol in the number of Liquors with which it will grow hot yet I have not met with any Liquor wherewith it came to a greater Incalescence than it frequently enough did with common Oyl of Turpentine For when we caused divers ounces of each to be well shaken together in a strong vessel fasten'd to prevent mischief to the end of a pole or staff the Ebullition was great and fierce enough to be not underservedly admired by the Spectators And this brings into my mind a pleasant adventure afforded by these Liquors of each of which having for the Production of Heat and other purposes caus'd a good bottle full to be put up with other things into
a box and sent down into the Countrey with a great charge that care should be had of the Glasses the Wagon in which the box was carried happen'd by a great jolt that had almost overturn'd it to be so rudely shaken that these Glasses were both broken and the Liquors mingling in the box made such a noise and stink and sent forth such quantities of smoke by the vents which the fumes had open'd to themselves that the Passengers with great outcries and much haste threw themselves out of the Wagon for fear of being burnt in it The Trials we made with Oyl of Turpentine when strong Spirit of Nitre was substituted in the stead of Oyl of Vitriol belong not to this place EXPER. XVIII BUt though Petroleum especially when rectified be as I have elsewhere noted a most subtile Liquor and the lightest I have yet had occasion to try yet to shew you how much the Incalescence of Liquors may depend upon their Texture I shall adde that having mixt by degrees one ounce of rectified Petroleum with an equal weight of strong Oyl of Vitriol the former Liquor seemed to work upon the Surface of this last named almost like a Menstruum upon a metal innumeious and small bubbles continually ascending for a while into the Oleum Petrae which had its colour manifestly alter'd and deepen'd by the operation of the spirituous parts But by all the action and re-action of these Liquors there was produced no such smoaking and boiling or intense heat as if Oyl of Turpentine had been employed instead of Oyl of Vitriol the change which was produc'd as to Qualities being but a kind of Tepidness discoverable by the Touch. Almost the like success we had in the Conjunction of Petroleum and Spirit of Nitre a more full account whereof may be elsewhere met with In this and the late Trials I did not care to make use of Spirit of Salt because at least if it be but ordinarily strong I found its operation on the Liquors above mention'd inconsiderable and sometimes perhaps scarce sensible in comparison of those of Oyl of Vitriol and in some cases of dephlegm'd Spirit of Nitre EXPER. XIX EXperienced Chymists will easily believe that 't were not difficult to multiply Instances of Heat producible by Oyl of Vitriol upon solid bodies especially Mineral ones For 't is known that in the usual preparation of Vitriolum Martis there is a great effervescence excited upon the affusion of the Oyl of Vitriol upon Filings of Steel especially if they be well drench'd in common water And it will scarce be doubted but that as Oyl of Vitriol will at least partly dissolve a great many both calcin'd and testaceous bodies as I have try'd with Lime Oyster-shells c. so it will during the dissolution grow sensibly if not intensely hot with them as I found it to do both with those newly named and others as Chalk Lapis Calaminaris c. with the last of which if the Liquor be strong it will heat exceedingly EXPER. XX. WHerefore I will rather take notice of its Operation upon Vegetables as bodies which corrosive Menstruums have scarce been thought fit to dissolve and grow hot with To omit then Cherries and divers Fruits abounding in watery juices with which perhaps on that very account Oyl of Vitriol will grow hot I shall here take notice that for trial sake having mixt a convenient quantity of that Liquor with Raisins of the Sun beaten in a Mortar the Raisins grew so hot that if I misremember not the Glass that contain'd it had almost burnt my hand These kind of Heats may be also produc'd by the mixture of Oyl of Vitriol with divers other Vegetable Substances but as far as I have observed scarce so eminently with any dry body as with the crumbs of white bread or even of brown with a little of which we have sometimes produced a surprising degree of Heat with strong or well-dephlegm'd Oyl of Vitriol which is to be suppos'd to have been employed in the foregoing Experiments and all others mention'd to be made by the help of that Menstruum in our Papers about Qualities unless it be in any particular case otherwise declared EXPER. XXI 'T Is as little observed that Corrosive Menstruums are able to work as such on the soft parts of dead Animals as on those of Vegetables and yet I have more than once produced a notable Heat by mixing Oyl of Vitriol with minced flesh whether roasted or raw EXPER. XXII THough common Sea-salt does usually impart some degree though not an intense one of Coldness unto common water during the act of Dissolution yet some Trials have informed me that if it were cast into a competent quantity of Oyl of Vitriol there would for the most part insue an Incalescence which yet did not appear to succeed so regularly as in most of the foregoing Experiments But that Heat should be produc'd usually though not perhaps constantly by the above-named Menstruum and Salt seems therefore worthy of our notice because 't is known to Chymists that common Salt is one main Ingredient of the few that make up common factitious Sal Armoniac that is wont to be sold in the Shops And I have been inform'd that the excellent Academians of Florence have observed that Oyl of Vitriol would not grow hot but cold by being put upon Sal Armoniac Something like which I took notice of in rectified Spirit of Sulphur made per Campanam but found the effect much more considerable when according to the Ingenious Florentine Experiment I made the Trial with Oyl of Vitriol which Liquor having already furnished us with as many Phaenomena for our present purpose as could be well expected from one Agent I shall scarce in this Paper about Heat make any farther use of it but proceed to some other Experiments wherein it does not intervene EXPER. XXIII WE took a good lump of common Sulphur of a convenient shape and having rub'd or chas'd it well we found as we expected that by this attrition it grew sensibly warm and That there was an intestine agitation which you know is Local Motion made by this attrition did appear not onely by the newly mention'd Heat whose nature consists in motion and by the antecedent pressure which was fit to put the parts into a disorderly vibration but also by the sulphureous steams which 't was easie to smell by holding the Sulphur to ones nose as soon as it had been rub'd Which Experiment though it may seem trivial in it self may be worth the consideration of those Chymists who would derive all the Fire and Heat we meet with in sublunary bodies from Sulphur For in our case a mass of Sulphur before its parts were put into a new and brisk motion was sensibly cold and as soon as its parts were put into a greater agitation than those of a mans fingers it grew sensibly hot which argues that 't was not by its bare presence or any emanative action as
the Filings of Steel the tincted Spirit of Wine was not at all impell'd up as before but rather after a while began to subside and fell though very slowly about a quarter of an inch The like Experiment being tried with powder'd Sublimate in common water the liquor in the Thermoscope was scarce at all sensibly either rais'd or deprest which argued the alteration as to Heat or Cold to have been either none or very inconsiderable Having given warning at the beginning of this Section that in it I aimed rather at offering various than numerous Experiments about the Production of Heat I think what has been already deliver'd may allow me to take leave of this Subject without mentioning divers Instances that I could easily adde but think it fitter at present to omit For those afforded me by Trials about Antiperistasis belong to a Paper on that Subject Those that might be offer'd about Potential Heat in humane bodies would perchance be thought but unnecessary after what has been said of Potential Coldness from which an attentive Considerer may easily gather what according to our Doctrine is to be said of the contrary Quality And divers Phaenomena which would have been of the most considerable I could have mentioned of the Production of Heat since in them that Quality is the most exalted I reserve for the Title of Combustibleness and Incombustibility having already suffer'd this Collection or rather Chaos of Particulars about the Production of Heat to swell to too great a bulk FINIS EXPERIMENTS AND OBSERVATIONS About the Mechanical Production OF TASTS By the Honourable ROBERT BOYLE Esq Fellow of the R. Society LONDON Printed by E. Flesher for R. Davis Bookseller in Oxford 1675. EXPERIMENTS AND OBSERVATIONS About the Mechanical Production OF TASTS TO make out the Mechanical Origine or Production of Sapors as far as is necessary for my present purpose 't will be expedient to premise in general that according to our notion of Tasts they may depend upon the bigness figure and motion of the saporifick corpuscles considered separately and as the affections of single and very minute particles of matter or else in a state of conjunction as two or more of these affections and the particles they belong to may be combined or associated either among themselves or with other particles that were not saporous before And as these Coalitions and other Associations come to be diversified so the Tasts resulting from them will be altered or destroyed But to handle these distinctly and fully were a task not onely too difficult and long but improper in this place where I pretend to deliver not Speculations but matters of Fact in setting down whereof nevertheless to avoid too much confusion I am content where I can doe it readily and conveniently in some of my Trials to couch such references as may best point at those Heads whence the Mechanical explications may be derived and consequently our Doctrine confirmed By Tast considered as belonging to the Object under which Notion I here treatof it I mean that quality or whatever else it be which enables a body by its operation to produce in us that sensation which we feel or perceive when we say we tast That this something whether you will call it a quality or whatever else it be that makes or denominates an object saporous or rather if I may be allowed a barbarous term saporifick may so depend upon the shape size motion and other Mechanical affections of the small parts of the tasted body and result from the association of two or more of them not excluding their congruity or incongruity to the organs of Tasting may be made probable by the following Instances EXPER. I. To divide a Body almost insipid into two Bodies of very strong and very differing Tasts 'T IS observed that Salt-peter refined and by that purification freed from the Sea-salt that is wont to be mingled with it does rather cool the tongue than make any great saporifick impressions on it And though I will not say that it is as some have thought an insipid body yet the bitterishness which seems to be its proper tast is but very faint and languid And yet this almost insipid body being distilled by the way of Inflammation which I elsewhere teach or even by the help of an additament of such clay as is it self a tastless body will afford a Nitrous spirit that is extreamly sharp or corrosive upon the tongue and will dissolve several Metals themselves and a fixt salt that is likewise very strongly tasted but of a tast altogether different from that of the Spirit that is extreamly sharp or corrosive upon the tongue and accordingly this salt will dissolve divers compact bodies that the other will not work on and will precipitate divers metals and other concretes out of those solutions that have been made of them by the Spirit EXPER. II. Of two Bodies the one highly Acid and corrosive and the other Alkalizat and fiery to produce a Body almost insipid THis may be performed by the way I have elsewhere mentioned of composing Salt-peter For if upon a liquour of fixt Nitre made per Deliquium you warily drop good Spirit of Nitre till it be just enough to satiate the Alkaly for if there be too much or too little the Experiment may miscarry we may by a gentle evaporation and sometimes without it and that in a few minutes obtain Crystals which being dried after they have been if it be needfull freed from any adhering particles not of their own nature will have upon the tongue neither a sharp nor an alkalizate tast but that faint and scarce sensible bitterness that belongs to Salt-peter if it be pure Salt-peter for the impure may perhaps strongly relish of the common Salt that is usually contained in it The like production of Salt-peter we have sometimes made in far less time and sometimes indeed in a trice by substituting in stead of the fixed Salt of Nitre the saline parts of good Pot-ashes carefully freed by solution and filtration from the earthy and feculent ones I have sometimes considered whether the Phaenomena of these two Experiments may not be explicated by supposing them to arise from the new magnitudes and figures of the particles which the fire by breaking them or forcibly rubbing them one against the other or also against the Corpuscles of the additament may be presumed to give them as if for example since we find the larger and best formed Crystals of Nitre to be of a prismatical shape with six sides we should suppose the corpuscles of Nitre to be little prisms whose angles and ends are too obtuse or blunt to make vigorous and deep impressions on the tongue and yet if these little prisms be by a violent heat split or otherwise broken or forcibly made as it were to grind one another they may come to have parts so much smaller than before and endowed with such sharp sides and angles that being dissolved and agitated by
full of juice of Apples a certain proportion of Mustard-seed with hopes it would make the Sider more spirituous and pickant he found to his wonder and loss that when he came to draw it it stank of Garlick so rank that every body rejected it I remember also that by fermenting a certain proportion for that we found requisite of semen Dauci with Beer or Ale the Liquour had a very pleasant Relish of Limon-pills But that seems much more considerable which I shall now add That with an insipid Metal and a very corrosive Menstruum one may compound a tast that I have several times observed to be so like a Vegetable that I presume it may deceive many This may be done by dissolving Gold without any gross Salt in the mixture of Aqua fortis and the Spirit of Salt or even in common Aqua Regis made by dissolving Sal Armoniac in Aqua fortis For if the Experiment be happily made one may obtain either a Solution or a Salt whose austere tast will very much resemble that of Sloes or of unripe Bullace And this tast with some little variety I found in Gold dissolved without any distilled Liquour at all and also if I much forget not in Gold that by a peculiar Menstruum I had volatilized The last Instance I shall give of the imitation of Tasts I found to have been for the main known to some ingenious Ladies But to make the Experiment succeed very well a due proportion is the principal Circumstance which is wont to be neglected I cannot readily call to mind that which I found to succeed best but the Trial may be indifferently well made after such a manner as this Take a pint or a pound of Malaga or Canary Sack for though French and the like Wines may serve the turn yet they are not so proper and put into it a drachm or two of good odoriferous Orrice Roots cut into thin slices and let them infuse in the Liquour a convenient time 'till you perceive that they have given it a desired tast and smell then keep the thus perfumed Wine exactly stopped in a cool place According to which way I remember that when I hit on the right proportion of Ingredients and kept them a due time in infusion I had many years ago a Wine which being coloured with Cocheneele or some such tingeing ingredient was taken for good Rasberry-Wine not onely by ordinary persons but among others by a couple of eminent Physicians one of whom pretended to an extraordinary criticalness of palate on such occasions both of them wondering how at such an unlikely time of the year as I chose to present them that Liquour among others I could have such excellent Rasberry-Wine Some of which to add that by the by I found to preserve the specifick tast two or three years after it was made A Short EXCURSION About some Changes made OF TASTS BY MATURATION IT will not perhaps be thought impertinent but rather necessary to add a word or two on this occasion for their sakes that think the Maturation of Fruits and the changes of Tasts by which 't is usually known must needs be the effect of the Vegetable Soul of the Plant. For after the Fruit is gathered and so by being no longer a part of the Tree does according to the most common opinion cease to be a part of the living Plant as a Hand or a Foot cut off is no more reckoned among the Lims of the man it belonged to yet 't is very possible that some Fruits may receive maturation after they have been severed from the Plants that bore them For not to mention that Apples gathered somewhat before the time by lying in heaps do usually obtain a mellowness which seems to be a kind or degree of Maturation or that Medlars gathered whilst they are hard and harsh do become afterwards in process of time soft and better tasted in which state though some say they are rotten yet others think that supposed rottenness is the proper Maturity of that kind of Fruit Not to mention these I say or the like Instances 't is a famous Assertion of several Writers of the Indian affairs that the Fruit they call Bananas is usually gathered green and hung up in bunches or clusters in the house where they ripen by degrees and have an advantageous change made both of their colour and of their tast And this an ancient acquaintance of mine a literate and observing person of whom I inquired about it assured me he had himself lately tried and found to be true in America And indeed I see not why a convenient degree of warmth whether external from the Sun and Fire or internal from some degree of fermentation or analogous intestine Commotion may not whether the Fruit be united to the Plant or no put the saporifick Corpuscles into motion and make them by various and insensible transcursions rub against each other and thereby make the little bodies more slender or thin and less rigid or cutting and harsh than they were before and by various motions bring the Fruit they compose to a state wherein it is more soft in point of consistence and abound in Corpuscles less harsh and more pliable than they were before and more congruous to the pores of the organ of Tast And in a word make such a change in the constitution of the Fruit as men are wont to express by the name of Maturity And that such Mechanical changes of Texture may much alter the Qualities and among them the Tast of a Fruit is obvious in bruised Cherries and Apples which in the bruised parts soon come to look and tast otherwise than they did before The possibility of this is also obvious by Wardens when slowly roasted in embers with so gentle a fire as not to burn off the paper they are wont to be wrapt in to be kept clean from the ashes And I have seen in the bordering Country betwixt France and Savoy a sort of Pears whose name I now remember not which being kept for some hours in a moderate heat in a Vessel exactly closed with embers and ashes above and beneath them will be reduced to a juicy Substance of a lovely red colour and very sweet and lushious to the tast Many other sorts of Fruit in other Countries if they were handled after the same way or otherwise skilfully wrought on by a moderate heat would admit as great alterations in point of tast Neither is that sort of Pear to be here omitted which by meer Compression duly ordered without external heat will in a few minutes be brought to exchange its former hardness and harshness for so yielding a Contexture and pleasant a tast as I could not but think very remarkable And that even more solid and stubborn Salts than those of Vegetables may have the sharpness and piercingness of their tasts very much taken off by the bare internal action of one part upon the other without the addition of any
strongly stinking Body to another of a not sweet smell to produce a mixture of a pleasant and strongly Aromatick odour WHat is here proposed is performed at the same time that the Eleventh of the foregoing Experiments of Tasts is made For the Liquour thereby produced if it be well prepared has not onely a spicy tast but also a kind of Aromatick and pleasant smell and I have some now by me that though kept not over-carefully does after some years retain much of its former odour though not so much as of its tast EXPER. VII By digesting two Bodies neither of them well sented to produce Bodies of a very subtile and strongly fragrant odour WE took a pound for instance of Spanish Wine and put to it some ounces of Oil of Vitriol then keeping them for a reasonable time in digestion we obtained as we expected a mixture odoriferous enough But this Triall you will find improved by that which insues EXPER. VIII By the bare addition of a Body almost inodorous and not well sented to give a pleasant and Aromatick smell to Spirit of Wine THis we have several times done by the ways elsewhere related for another scope the summ of which as far as it needs be mentioned in this place is this We took good Oil of blew Vitriol that was brought from Dantzick though the very common will serve well and having put to it by degrees an equal weight of Spirit of Wine totally inflammable we digested them together for two three or four weeks sometimes much longer and then with better success from which when we came to distill the mixture we had a very fragrant Spirit which was sometimes so subtile that though distilled in a tall Glass with a gentle Heat it would in spite of our care to secure the closeness of the Vessels at the junctures pierce through and fill the Laboratory with a perfume which though men could not guess what body afforded it yet they could not but wonder at it Whence we may learn both how much those spirituous and inflammable particles the Chymists call the vegetable Sulphur of Wine may work on and ennoble a mineral Sulphur for that such an one there is in Oil of Vitriol I have elsewhere proved by experience and how much the new Commistions and Contextures made by digestion may alter the odours of Bodies whether Vegetable or Mineral That also another Constitution of the same matter without any manifest addition or recess of particles may proceed to exhibit a very differing smell will appear by the following Triall EXPER. IX To make the forementioned fragrant Body without addition or fire degenerate into the rank smell of Garlick TO make out this I need onely relate that I have more than once put the above mentioned fragrant Liquour in stopt Glasses whereof the one and not the other stood in a warm place till in process of time I found that odoriferous Liquour so to degenerate in point of sent that one would have thought it to have been strongly infected with Garlick And the like unpleasant Smell I observed in a certain Oil made of Vegetable and Mineral Substances distilled together And on this occasion I will add though not as an Argument this Observation which though I shall not undertake it will always succeed I think may not impertinently be set down in this place partly because of the likeness of the odour produced to that which was the effect of the last named Triall and partly or rather chiefly because it may shew us that a Body which it self is not onely inodorous but very fixt may yet in some cases have a great stroke in the Phaenomena of Odours whether by being wrought on by and sometimes mingled with the parts of the odorous body and thereby giving it a new modification I shall not now stay to enquire We took then good Salt of Tartar and put to it several times its weight of the expressed juice of Onions we kept them in a light digestion for a day or two and then unstopping the Vial we found the former smell of the Onions quite degenerated into a rank smell of Garlick as was judged even when fresh juice of Garlick was procured to compare them To vary this Experiment we made with fixt Salts and some other strongly sented Juices Trialls whose events 't would perhaps be tedious here to relate EXPER. X. With an inodorous Body and another not well-sented to produce a muskie smell THis we have sometimes done by casting into Spirit not Oil of Vitriol a large proportion of small Pearls unbroken For the action of the acid Menstruum upon these being moderated partly by the weakness of the Menstruum and partly by the intireness of the Pearls the dissolution would sometimes last many hours Holding from time to time my nose to the open orifice of the Glass 't was easie to perceive a pleasant muskie smell which also others to whom I mentioned it took notice of as well as I. And if I misremember not I took notice of the like smell upon Pearls not onely dissolved in Spirit of Vinegar but in another Liquour that had but a bad sent of its own The foregoing Experiment calls to my mind that which follows EXPER. XI With fixt Metals and Bodies either inodorous or stinking to produce strong and pleasant smells like those of some Vegetables and Minerals THat Gold is too fixt a body to emit any odour and that Aqua Regis has an odour that is very strong and offensive I think will be easily granted But yet Aurum fulminans being made as 't is known by precipitating with the inodorous Oil of Tartar the Solution made of the former in the latter and this Precipitate being to be farther proceeded with in order to another Experiment we fulminated it per se in a Silver Vessel like that but better contrived that is if I misremember not somewhere described by Glauberus And among other Phaenomena of this operation that belong not to this place we observed with pleasure that when the fulmination was recently made the steams which were afforded by the metal that had been fired were endowed with a delightful smell not unlike that of musk From which Experiment and the foregoing we may learn that Art by lucky Contextures may imitate the odours that are presumed to be natural and specifick and that Mineral and Vegetable Substances may compound a smell that is thought to be peculiar to Animals And as Art sometimes imitates Nature in the production of Odours as may be confirmed by what is above related concerning counterfeit Rasberry-Wine wherein those that drank it believed they did not onely tast but smell the Rasberry so sometimes Nature seems to imitate her self in giving like odours to bodies extreamly differing For not yet to dismiss the smell of Musk there is a certain Seed which for the affinity of its odour to that perfume they call the Musk-seed and indeed having some of it presented me by a
couple of imperfections that more particularly relate to the Doctrine of Qualities And first I do not think it a Convincing Argument that is wont to be imployed by the Aristotelians for their Elements as well as by the Chymists for their Principles that because this or that Quality which they ascribe to an Element or a Principle is found in this or that body which they call mixt therefore it must owe that Quality to the participation of that Principle or Element For the same Texture of parts or other modification of matter may produce the like Quality in the more simple and the more compounded body and they may both separately derive it from the same Cause and not one from the Participation of the other So Water and Earth and Metals and Stones c. are heavy upon the account of the common Cause of Gravity and not because the rest partake of the Earth as may appear in Elementary water which is as simple a body as it and yet is heavy So water and oil and exactly deflegm'd Spirit of Wine and Mercury and also Metals and Glass of Antimony and Minium or calcin'd Lead whilest these three are in fusion are fluid being made so by the variously determined motions of their minute parts and other Causes of Fluidity and not by the participation of water since the arid Calces of Lead and Antimony are not like to have retained in the fire so volatile a liquor as water and since Fluidity is a Quality that Mercury enjoys in a more durable manner than Water it self For that metalline liquor as also Spirit of Wine well Rectified will not be brought to freeze with the highest degree of Cold of our sharpest winters though a far less degree of Cold would make water cease to be fluid and turn it into Ice To this I shall only add in the second place that 't is not unpleasant to see how arbitrarily the Peripateticks derive the Qualities of bodies from their four Elements as if to give an instance in the lately named Quality Liquidity you shew them exactly deflegmed Spirit of Wine and ask them whence it has its great Fluidness they will tell you from water which yet is far less fluid than it and this spirit of wine it self is much less so than the flame into which the spirit of wine is easily resoluble But if you ask whence it becomes totally inflammable they must tell you from the fire and yet the whole body at least as far as sense can discover is fluid and the whole body becomes flame and then is most fluid of all so that fire and water as contrary as they make them must both be by vast odds predominant in the same body This spirit of wine also being a liquor whose least parts that are sensible are actually heavy and compose a Liquor which is seven or eight hundred times as heavy as Air of the same bulk which yet experience shews not to be devoid of weight must be supposed to abound with Earthy particles and yet this spirituous liquor may in a trice become Flame which they would have to be the lightest body in the world But to enlarge on this subject would be to forget that the design of this Tract engages me to deal not with the Peripatetic School but the Spagyrical To which I shall therefore return and give you this advertisement about it that what I have hitherto objected is meant against the more common and received Doctrine about the Material Principles of bodies reputed mixt as 't is wont by vulgar Chymists to be applied to the rendring an account of the Qualities of substances Corporeal and therefore I pretend not that the past objections should conclude against other Chymical Theories than that which I was concerned to question And if adept Philosophers supposing there be such or any other more than ordinarily Intelligent Spagyrists shall propose any particular Hypotheses differing from those that I have questioned as their Doctrine and Reasons are not yet known to me so I pretend not that the past Arguments should conclude against them and am willing to think that Persons advantaged with such peculiar opportunities to dive into the Mysteries of Nature will be able to give us if they shall please a far better account of the Qualities of bodies than what is wont to be proposed by the generality of Chymists Thus dear Pyrophilus I have laid before you some of the chief Imperfections I have observed in the vulgar Chymists Doctrine of Qualities and consequently I have given you some of the chief Reasons that hinder me from acquiescing in it And as my objections are not taken from the Scholastical subtleties nor the doubtful speculations of the Peripateticks or other Adversaries of the Hermetick Philosophy but from the nature of things and from Chymical experiments themselves so I hope if any of your Spagyrical friends have a minde to convince me he will attempt to doe it by the most proper way which is by actually giving us clear and particular explications at least of the grand Phaenomena of Qualities which if he shall do he will find me very ready to acquiesce in a Truth that comes usher'd in and endear'd by so acceptable and useful a thing as a Philosophical Theory of Qualities FINIS REFLECTIONS UPON THE Hypothesis OF ALCALI and ACIDUM By the Honourable ROBERT BOYLE Esq Fellow of the R. Society LONDON Printed by E. Flesher for R. Davis Bookseller in Oxford 1675. THough the following Discourse was at first written by way of Appendix to the Treatise of the Imperfection of the Chymical Doctrine of Qualities yet the bulk of it swelling beyond what was foreseen made it seem expedient to publish it as a Tract by it self REFLECTIONS UPON THE Hypothesis OF Alcali and Acidum CHAP. I. I Presume it will not be difficult to discern that much of what has been said about the Imperfection of the vulgar Chymical Doctrine concerning Qualities may with easie variations be applied to some other Hypotheses that are of kin to that Doctrine and particularly to their Theory that would derive both the Qualities of Bodies and the rest of the Phaenomena of Nature from what they call Acidum and Alcali For though these two differences may be met with in a great number and variety of bodies and consequently the Consideration of them may frequently enough be of good use especially to Spagyrists and Physitians when they are conversant about the secondary and if I may so call them Chymical Causes and Operations of divers mixt bodies yet I confess I cannot acquiesce in this Hypothesis of Alkali and Acidum in the latitude wherein I find it urged and applied by the Admirers of it as if it could be usefully substituted in the place of Matter and Motion The Hypothesis being in a sort subordinate to that of the tria prima in ascribing to two contrary saline Principles what vulgar Chymists do to their Salt Sulphur and Mercury most of the
to be stopt and detained by other bodies or entangled among themselves and consequently very difficult to be carried upwards in regard that whilst they are thus fastened either to one another or to any stable body each single Corpuscle is not onely to be considered as having its own peculiar bulk since its cohesion with the other corpuscle or body that detains it makes them fit to be look'd upon per modum Unius that degree of heat they are exposed to being presumed uncapable of disjoyning them And this may be one Reason why Water though it be specifically heavier than Oil yet is much more easily brought to exhale in the form of vapours than is Oil whose corpuscles by the lasting stains they leave on cloath wood wool c. which water will but transiently moisten not stain seems to be of very intangling figures The fourth and last qualification requisite in a Volatile body is that the parts do loosely adhere or at least be united in such a manner as does not much indispose them to be separated by the fire in the form of fumes or vapours For he that considers the matter will easily grant that if the contexture of the corpuscles whereof a body consists be intricate or their cohesion strong their mutual implication or their adherence to each other will make one part hinder another from flying separately away and their conjunction will make them too heavy or unweildy to be elevated together as intire though compounded parts Thus we see that in Spring or the beginning of Summer a wind though not faint is unable to carry off the lightest leaves of trees because they stick fast to the bows and twigs on which they grow but in Autumn when that adhesion ceases and the leaves sit but loosely on a wind no stronger than that they resisted before will with ease blow them off and perhaps carry them up a good way into the Air. But here note that it was not without some cause that I added above that in a fluid body the parts should at least be united in such a manner as does not much indispose them to be separated For 't is not impossible that the parts of a body may by the figures and smoothness of the surfaces be sufficiently apt to be put into motion and yet be indisposed to admit such a motion as would totally separate them and make them fly up into the Air. As if you take two pieces of very flat and well-polished marble or glass and lay them one upon the other you easily make them slide along each others surfaces but not easily pull up one of them whilest the other continues its station And when Glass is in the state of fusion the parts of it will easily slide along each other as is usual in those of other fluids and consequently change places and yet the continuity of the whole is not intirely broken but every corpuscle does somewhere touch some other corpuscle and thereby maintain the cohesion that indisposes it for that intire separation accompanied with a motion upwards that we call avolation And so when Salt-peter alone is in a Crucible exposed to the fire though a very moderate degree of it will suffice to bring the Salt to a state of fusion and consequently to put the corpuscles that compose it into a restless motion yet a greater degree of heat than is necessary to melt it will not extricate so much as the Spirits and make them fly away CHAP. III. THE foregoing Doctrine of the Volatility of bodies may be as well illustrated as applied if we proceed to deduce from it the generall ways of Volatilization of bodies or of introducing volatility into an assigned portion of matter For these wayes seem not inconveniently reducible to five which I shall severally mention though Nature and Art do usually imploy two or more of them in conjunction For which Reason I would not when I speak of one of these wayes be understood as if excluding the rest I meant that no other concurred with it The first of the five ways or means of Volatilizing a body is to reduce it into minute parts and caeteris paribus the more minute they are the better That the bringing a body into very minute parts may much conduce to the volatilizing of it may be gathered from the vulgar practice of the Chymists who when they would sublime or distill Antimony Sal Armoniac Sea-salt Nitre c. are wont to beat them to powders to facilitate their receiving a further comminution by the action of the fire And here I observe that in some bodies this comminution ought not to be made onely at first but to be continued afterwards For Chymists find by experience though perhaps without considering the reason of it that Sea-salt and Nitre will very hardly afford their Spirits in Distillations without they be mingled with powdered clay or bole or some such other additament which usually twice or thrice exceeds the weight of the Salt it self Although these additaments being themselves fixt seem unlikely to promote the volatilization of the bodies mixt with them yet by hindering the small grains of Salt to melt together into one lump or masse and consequently by keeping them in the state of Comminution they much conduce to the driving up of the Spirits or the finer parts of the Salts by the operation of the fire But to prosecute a little what I was saying of the Conduciveness of bringing a body into small parts to the volatilization of it I shall add that in some cases the Comminution may be much promoted by employing Physical after Mechanical ways and that when the parts are brought to such a pitch of exiguity they may be elevated much better than before Thus if you take filings of Mars and mix them with Sal Armoniack some few parts may be sublimed but if as I have done you dissolve those filings in good Spirit of Salt instead of Oil of Vitriol and having coagulated the solution you calcine the greenish Crystalls or vitriolum Martis that will be afforded you may with ease and in no long time obtain a Crocus Martis of very fine parts so that I remember when we exquisitely mingled this very fixt powder with a convenient proportion of Sal Armoniac and gradually press'd it with a competent fire we were able to elevate at the first Sublimation a considerable part of it and adding a like or somewhat inferiour proportion of fresh Sal Armoniac to the Caput Mortuum we could raise so considerable a part of that also and in it of the Crocus that we thought if we had had Conveniency to pursue the operation we should by not many repeated Sublimations have elevated the whole Crocus which to hint that upon the by afforded a Sublimat of so very astringent a Tast as may make the trial of it in stanching of blood stopping of fluxes and other cases where potent astriction is desired worthy of a Physicians Curiosity CHAP. IV. THE
second means to volatilize bodies is to rub grind or otherwise reduce their corpuscles to be either smooth or otherwise fitly shaped to clear themselves or be disintangled from each other By reason of the minuteness of the corpuscles which keeps them from being separately discernible by the Eye 't is not to be expected that immediate and ocular Instances should be given on this occasion but that such a change is to be admitted in the small parts of many bodies brought to be volatile seems highly probable from the account formerly given of the requisites or conditions of Volatility whose introduction into a portion of matter will scarce be explicated without the intervention of such a change To this second Instrument of Volatilization in concurrence with the first may probably be referred the following Phaenomena In the two first-of which there is imployed no additional volatile Ingredient and in the fourth a fixt body is disposed to volatility by the operation of a Liquour though this be carefully abstracted from it 1. If Urine freshly made be put to distill the Phlegm will first ascend and the Volatile salt will not rise 'till that be almost totally driven away and then requires a not inconsiderable degree of fire to elevate it But if you putrefie or digest Urine though in a well-closed Glass-Vessel for seven or eight weeks that gentle warmth will make the small parts so rub against or otherwise act upon one another that the finer ones of the Salt will perhaps be made more slender and light and however will be made to extricate themselves so far as to become volatile and ascending in a very gentle heat leave the greatest part of the phlegm behind them 2. So if Must or the sweet juice of Grapes be distilled before it have been fermented 't is observed by Chymists and we have tried the like in artificial Wine made of Raisins that the phlegm but no ardent Spirit will ascend But when this Liquour is reduced to Wine by fermentation which is accompanied with a great and intestine commotion of the justling parts hitting and rubbing against one another whereby some probably come to be broken others to be variously ground and subtilized the more subtile parts of the Liquour being extricated or some of the parts being by these operations brought to be subtile they are qualified to be raised by a very gentle heat before the phlegm and convene into that fugitive Liquour that Chymists for its activity call Spirit of Wine Nor is it onely in the slighter Instances afforded by Animals and Vegetables that Volatility may be effected by the means lately mentioned For experience hath assured me that 't is possible by an artificial and long digestion wherein the parts have leisure for frequent justlings and attritions so to subtilize and dispose the corpuscles even of common Salt for Volatility that we could make them ascend in a moderate fire of Sand without the help of Bole Oil of Vitriol or any Volatilizing additament and which is more considerable the Spirit would in rising precede the Phlegm and leave the greatest part thereof behind it This intestine commotion of parts capable of producing Volatility in the more disposed portions of a body though it be much more easie to be found in Liquours or in moist and soft bodies yet I have sometimes though rarely met with it in dry ones And particularly I remember that some years ago having for trial sake taken Mustard-seed which is a body pregnant with subtile parts and caused it to be distilled per se in a Retort I had as I hoped without any more ado a great many grains of a clear and figured Volatile salt at the very first distillation which Experiment having for the greater security made a second time with the like success I mentioned it to some Lovers of Chymistry as what I justly supposed they had not heard of I leave it to farther Inquiry whether in a body so full of Spirits as Mustard-seed the action and re-action of the parts among themselves perhaps promoted by just degrees of fire might not suffice to make in them a change equivalent in order to Volatilization and the yielding a Volatile Salt to that which we have observed Fermentation and Putrefaction to have made in the juice of Grapes Urine and some other bodies How far the like success may be expected in other Trialls I cannot tell especially not having by me any Notes of the events of some Attempts which that Inquiry put me upon Onely I remember in general that as some trials I made with other Seeds and even with Aromatick ones did not afford me any Volatile Salt so the success of other trials made me now and then think that some subjects of the Vegetable kingdom whence we are wont to drive over acid Spirits but no dry Salt may be distilled with so luckily regulated a heat as to afford something though but little of Volatile Salt and that perhaps more bodies would be found to doe so were they not too hastily or violently prest by the fire whereby such saline schematisms of the desired parts of the matter are by being dissipated or confounded destroyed or vitiated as in a slow dextrous or fortunate way of management would come forth not in a liquid but a saline form Of which Observation we may elsewhere mention some Instances and shall before the close of this Paper name one afforded us by crude Tartar 3. Though Silver be one of the fixedst bodies that we know of yet that 't is not impossible but that chiefly by a change of Texture it may strangely be disposed to Volatility I was induced to think by what I remember once happened to me A Gentleman of my acquaintance studious of Chymical Arcana having lighted on a strange Menstruum which he affirmed and I had some cause to believe not to be corrosive he abstracted it from several metalls for the same Liquour would serve again and again and brought me the Remainders with a desire that I would endeavour to reduce those of Lead and Silver into the pristine metals again which he had in vain attempted to doe whereupon though I found the white Calx of Lead reducible yet when I came to the Calx of Silver I was not able to bring it into a body and having at length melted some Lead in a gentle fire to try whether I could make it swallow up the Calx in order to a farther operation I was not a little surprized to find that this mild heat made the Calx of Silver presently fly away and sublime in the form of a farina volatilis which whitened the neighbouring part of the Chimney as well as the upper part of the Crucible 4. From that which Chymists themselves tell us I think we may draw a good Argument ad hominem to prove that Volatility depends much upon the texture and other Mechanical affections of a body For divers of those Hermetick Philosophers as they are called that
in close Vessels be made to carry over with it some of the Lead As we clearly found by the increased weight of the Quick-silver that passed into the Receiver which by the way may make us cautious how we conclude Quick-silver to be pure meerly from its having been distilled over There remains but one body more heavy than those I come from naming and that is Gold which being also of a fixity so great that 't is indeed admirable I doe not wonder that not onely the more wary Naturalists but the more severe among the Chymists themselves should think it incapable of being volatilized But yet if we consider how very minute parts Gold may be rationally supposed to consist of and to be divisible into me thinks it should not seem impossible that if men could light on Volatil Salts endowed with figures fit to stick fast to the corpuscles of the Gold they would carry up with them bodies whose solidity can scarce be more extraordinary than their minuteness is And in effect we have made more than one Menstruum with which some particles of Gold may be carried up But when I employed that which I recommended to you formerly under the name of Menstruum peracutum which consists mainly and sometimes onely of Spirit of Nitre several times drawn from Butter of Antimony I was able without a very violent fire in a few hours to elevate so much crude Gold as in the neck of the Retort afforded me a considerable Quantity of Sublimate which I have had red as blood and whose consisting partly of Gold manifestly appeared by this that I was able with ease to reduce that metall out of it In reckoning up the Instruments of Volatilization we must not quite leave out the mention of the Air which I have often observed to facilitate the elevation of some bodies even in close Vessels wherein though to fill them too full be judged by many a Compendious practise because the steams have a less way to ascend yet Experience has several times informed me that at least in some cases they take wrong measures and that to pass by another Cause of their disappointment a large proportion of Air purposely left in the Vessels may more than compensate the greater space that is to be ascended by the vapours or exhalations of the matter that is to be distilled or sublimed And if in close Vessels the presence of the Air may promote the ascension of bodies it may well be expected that the elevation of divers of them may be furthered by being attempted in open Vessels to which the Air has free access And if we may give any credit to the probable Relations of some Chymists the Air does much contribute to the volatilization of some bodies that are barely though indeed for no short time exposed to it But the account on which the Air by its bare presence or peculiar operations conduces to the Volatilization of some bodies is a thing very difficult to be determined without having recourse to some Notions about Gravity and Levity and of the Constitution of the corpuscles that compose the Air which I take to be both very numerous and no less various And therefore I must not in these occasional Notes lanch out into such a Subject though for fear I should be blamed for too much slighting my old acquaintance the Air I durst not quite omit the power it has to dispose some bodies to Volatility A moderate attention may suffice to make it be discerned that in what hath been hitherto delivered I have for the most part considered the small portions of matter to be elevated in Volatilization as intire Corpuscles And therefore it may be now pertinent to intimate in a Line or two that there may be also Cases wherein a kind of Volatilization improperly so called may be effected by making use of such additaments as break off or otherwise divide the particles of the corpuscles to be elevated and by adhering to and so clogging one of the particles to which it proves more congruous inable the other which is now brought to be more light or disingaged to ascend This may be illustrated by what happens when Sal Armoniac is well ground with Lapis Calaminaris or with some fix'd Alkali and then committed to distillation For the Sea-salt that enters the Composition of the Sal Armoniac being detained by the stone or the Alkali there is a divorce made between the common Salt and the urinous and fuliginous Salts that were incorporated with it and being now disingaged from it are easily elevated I elsewhere mention that I have observed in Man's Urine a kind of native Sal Armoniac much less Volatile than the fugitive that is sublim'd from Man's Blood Harts-horn c. and therefore supposing that a separation of parts may be made by an Alkali as well in this Salt as in the common factitious Sal Armoniac I put to fresh Urine a convenient proportion which was a plentifull one of Salt of Pot-ashes that being then at hand and distilling the Liquor it yielded according to expectation a Spirit more Volatile than the Phlegm and of a very piercing tast which way of obtaining a Spirit without any violence of fire and without either previously abstracting the Phlegm as we are fain to do in fresh Urine or tediously waiting for the fermentation of stale Urine I taught some Chymists because of the usefulness of Spirit of Urine which being obtained this innocent way would probably be employed with much less suspicion of corrosiveness than if in the operation I had made use of Quick-lime Another Illustration of what I was not long since saying may be fetch'd from the Experiment of making Spirit of Nitre by mixing Salt-peter with Oil of Vitriol and distilling them together For the Oil does so divide or break the corpuscles of the Nitre that the now-disposed particles of that Salt which amount to a great portion of the whole will be made easily enough to ascend even with a moderate fire of Sand and sometimes without any fire at all in the form of Spirits exceeding unquiet subtle and apt to moak away To which Instances of this imperfect kind of Volatilization more might be added but that you may well think I have detain'd you but too long already with indigested Notes about one Quality CHAP. VII THe last means of Volatilizing bodies is the operation of the Fire or some other actual Heat But of this which is obvious it would be superfluous to discourse Onely this I shall intimate that there may be bodies which in such degrees of fire as are wont to be given in the vulgar operations of Chymists will not be elevated which yet may be forced up by such violent and lasting fires as are employed by the Melters of Ores and Founders of Guns and sometimes by Glass-makers And on this Consideration I shall here observe to you since I did not doe it at my entrance on these Notes that Chymists are wont to
precipitated them not with a Solution of Salt but the Spirit of Salt the phlegm being abstracted and some few of the looser saline particles though the remaining masse were prest with a violent fire that kept the Retort red-hot for a good while yet the Nitrous and Saline spirits would by no means be driven away from the Silver but continued in fusion with it and when the masse was taken out these Spirits did so abound in it that it had no appearance of a Metal but looked rather like a thick piece of Horn. The next Instance I shall name is afforded us by that kind of Turbith which may be made by Oil of Vitriol in stead of the Aqua fortis imployed in the common Turpethum Minerale For though Oil of Vitriol be a distilled liquour and Mercury a body volatile enough yet when we abstracted four or five parts of Oil of Vitriol from one of Quick-silver especially if the operation were repeated and then washed off as much as we could of the saline particles of the Oil of Vitriol yet those that remained adhering to the Mercury made it far more fixt than either of the liquours had been before and inabled it even in a Crucible to endure such a degree of fire before it could be driven away as I confess I somewhat wondered at The like Turbith may be made with Oil of Sulphur per Campanam But this is nothing to what Helmont tells us of the operation of his Alkahest where he affirms that that Menstruum which is volatile enough being abstracted from running Mercury not onely coagulates it but leaves it fixt so that it will endure the brunt of fires acuated by Bellows omnem follium ignem If this be certain it will not be a slender proof that Fixity may be Mechanically produced and however the Argument will be good in reference to the Helmontian Spagyrists For if as one would expect there do remain some particles of the Menstruum with those of the metal it will not be denied that two volatile substances may perfectly fix one another And if as Helmont seems to think the Menstruum be totally abstracted this supposition will the more favour our Doctrine about Fixity since if there be no material additament left with the Quick-silver the Fixation cannot so reasonably be ascribed to any thing as to some new Mechanical modification and particularly to some change of Texture introduced into the Mercury it self And that you may think this the less improbable I will now proceed to some Instances whereof the first shall be this That having put a mixture made of a certain proportion of two dry as well as volatile bodies viz. Sal Armoniac and Flower or very fine powder of Sulphur to half its weight of common running Mercury and elevated this mixture three or four times from it in a conveniently shaped and not over-wide glass the Mercury that lay in the bottom in the form of a ponderous and somewhat purplish powder was by this operation so fixt that it long endured a strong fire which at length was made so strong that it melted the Glass and kept it melted without being strong enough to force up the Mercury which by some trials not so proper to be here mentioned seemed to have its salivating and emetick powers extraordinarily infringed and sometimes quite suppressed But this onely upon the bye In all the other Instances wherewith I shall conclude these Notes I shall employ one Menstruum Oil of Vitriol and shew you the efficacy of it in fixing some parts of volatile bodies with some parts of it self by which examples it may appear that a Volatile body may not onely lessen the volatility of another body as in the lately mentioned case of our spirituous Sal Armoniac but that two Substances that apart were volatile may compose a third that will not onely be less volatile but considerably if not altogether fixt We mixed then by degrees about equal parts of Oil of Vitriol and Oil of Turpentine and though each of them single especially the latter will ascend with a moderate fire in a Sand-furnace yet after the Distillation was ended we had a considerable quantity sometimes if I mis-remember not a fifth or sixth part of a Caput Mortuum black as a Coal and whereof a great part was of a scarce to be expected fixtness in the fire To give a higher proof of the disposition that Oil of Vitriol has to let some of its parts grow fixt by combination with those of an exceeding volatile additament I mixed this liquour with an equal or double weight of highly rectified Spirit of Wine and not onely after but sometimes without previous digestion I found that the fluid parts of the mixture being totally abstracted there would remain a pretty quantity of a black Substance so fixt as to afford just cause of wonder And because Camphire is esteemed the most fugitive of consistent bodies in regard that being but laid in the free air without any help of the fire it will fly all away I tried what Oil of Vitriol abstracted from Camphire would doe and found at the bottom of the Retort a greater quantity than one would expect of a Substance as black as pitch and almost as far from the volatility as from the colour of Camphire though it appeared not that any of the Gum had sublim'd into the neck of the Retort From all which Instances it seems manifestly enough to follow that in many cases there needs nothing to make associated particles whether volatile or not become fixt but either to implicate or intangle them among themselves or bring them to touch one another according to large portions of their surfaces or by both these ways conjoyntly or by some others to procure the firm Cohaesion of so many particles that the resulting Corpuscles be too big or heavy to be by the degree of fire wherein they are said to be fixt driven up into the Air. FINIS Experiments and Notes ABOUT THE MECHANICAL ORIGINE OR PRODUCTION OF CORROSIVENESS AND CORROSIBILITY By the Honourable ROBERT BOYLE Esq Fellow of the R. Society LONDON Printed by E. Flesher for R. Davis Bookseller in Oxford 1675. Experiments and Notes ABOUT THE MECHANICAL PRODUCTION OF CORROSIVENESS AND CORROSIBILITY SECT I. About the Mechanical Origine of Corrosiveness I Do not in the following Notes treat of Corrosiveness in their strict sense of the word who ascribe this Quality only to Liquors that are notably acid or sowre such as Aqua fortis Spirit of Salt Vinegar Juice of Lemons c. but that I may not be oblig'd to overlook Unnous Oleous and divers other Solvents or to coin new names for their differing Solutive Powers I presume to employ the word Corrosiveness in a greater lautude so as to make it almost equivalent to the Solutive power of Liquors referring other Menstruums to those that are Corrosive or fretting though not always as to the most proper yet as to the principal and best known
species which I the less scruple here to do because I have elsewhere more distinctly enumerated and sorted the Solvents of bodies The Attributes that seem the most proper to qualifie a Liquor to be Corrosive are all of them Mechanical being such as are these that follow First That the Menstruum consist of or abound with Corpuscles not too big to get in at the Pores or Commissures of the body to be dissolved nor yet be so very minute as to pass through them as the beams of Light do through Glass or to be unable by reason of their great slenderness and flexibility to disjoyn the parts they invade Secondly That these Corpuscles be of a shape â—itting them to insinuate themselves more or less into the Pores or Commissures above-mentioned in order to the dissociating of the solid parts Thirdly That they have a competent degree of solidity to disjoyn the Particles of the body to be dissolved which Solidity of Solvent corpuscles is somewhat distinct from their bulk mention'd in the first Qualification as may appear by comparing a stalk of Wheat and a metalline Wire of the same Diameter or a flexible wand of Osier of the bigness of ones little finger with a rigid rod of Iron of the same length and thickness Fourthly That the Corpuscles of the Menstruum be agile and advantaged for motion such as is fit to disjoyn the parts of the invaded body either by their shape or their minuteness or their fitness to have their action befriended by adjuvant Causes such as may be first the pressure of the Atmosphere which may impell them into the Pores of bodies not fill'd with a Substance so resisting as common Air As we see that water will by the prevalent pressure of the Ambient whether Air or Water be raised to the height of some inches in capillary Glasses and in the pores of Spunges whose consistent parts being of easier cession than the sides of Glass-pipes those Pores will be enlarged and consequently those sides disjoyn'd as appears by the dilatation and swelling of the Spunge And secondly the agitation that the intruding Corpuscles may be fitted to receive in those Pores or Commissures by the transcursion of some subtile ethereal matter or by the numerous knocks and other pulses of the swimming or tumbled Corpuscles of the Menstruum it self which being a fluid body must have its small parts perpetually and variously moved whereby the engaged Corpuscles like so many little Wedges and Leavers may be enabled to wrench open or force asunder the little parts between which they have insinuated themselves But I shall not here prosecute this Theory which to be handled fully would require a discourse apart since these Conjectures are propos'd but to make it probable in the general That the Corrosiveness of bodies may be deduced from Mechanical Principles But whether best from the newly propos'd ones or any other need not be anxiously consider'd in these Notes where the things mainly intended and rely'd on are the Experiments and Phaenomena themselves EXPER. I. 'T Is obvious that though the recently exprest Juice of Grapes be sweet whilst it retains the Texture that belongs to it as 't is new especially if it be made of some sorts of Grapes that grow in hot Regions yet after fermentation 't will in tract of time as 't were spontaneously degenerate into Vinegar In which Liquor to a multitude of the more solid Corpuscles of the Must their frequent and mutual Attritions may be supposed to have given edges like those of the blades of swords or knives and in which perhaps the confused agitation that preceded extricated or as it were unsheathed some acid particles that deriv'd from the sap of the Vine or perchance more originally from the juice of the Earth were at first in the Must but lay conceal'd and as it were sheathed among the other particles wherewith they were associated when they were prest out of the Grapes Now this Liquor that by the forementioned or other like Mechanical Changes is become Vinegar does so abound with Corpuscles which on the account of their edges or their otherwise sharp and penetrative shape are Acid and Corrosive that the better sort of it will without any preparation dissolve Coral Crabs-eyes and even some Stones Lapis stellaris in particular as also Minium or the Calx of Lead and even crude Copper as we have often tried And not onely the distill'd Spirit of it will do those things more powerfully and perform some other things that meer Vinegar cannot but the saline particles wont to remain after Distillation may by being distill'd and cohobated per se or by being skilfully united with the foregoing Spirit be brought to a Menstruum of no small efficacy in the dissolution and other preparations of metalline bodies too compact for the meer Spirit it self to work upon From divers other sweet things also may Vinegar be made and even of Honey skilfully fermented with a small proportion of common water may be made a Vinegar stronger than many of the common Wine-vinegars as has been affirmed to me by a very candid Physician who had occasion to deal much in Liquors EXPER. II. NOt onely several dry Woods and other Bodies that most of them pass for insipid but Honey and Sugar themselves afford by Distillation Acid Spirits that will dissolve Coral Pearls c. and will also corrode some Metals and metalline Bodies themselves as I have often found by Trial. So that the violent Operation of the fire that destroys what they call the Form of the distill'd body and works as a Mechanical Agent by agitating breaking dissipating and under a new constitution reassembling the parts procures for the Distiller an Acid Corrosive Menstruum which whether it be brought to pass by making the Corpuscles rub one another into the figure of little sharp blades or by splitting some solid parts into sharp or cutting Corpuscles or by unsheathing as it were some parts that during the former Texture of the body did not appear to be acid or whether it be rather effected by some other Mechanical way may in due time be further considered EXPER. III. 'T Is observ'd by Refiners Goldsmiths and Chymists that Aqua Fortis and Aqua Regia which are Corrosive Menstruums dissolve Metals the former of them Silver and the latter Gold much more speedily and copiously when an external heat gives their intestine motions a new degree of Vehemency or Velocity which is but a mechanical thing and yet this superadded measure of Agitation is not onely in the abovemention'd Instances a powerfully assistant Cause in the Solutions made by the lately mention'd Corrosive Liquors but is that without which some Menstruums are not wont sensibly to corrode some bodies at all as we have tried in keeping Quick-silver in three or four times its weight of Oyl of Vitriol since in this Menstruum I found not the Mercury to be dissolved or corroded though I kept it a long time in
the Cold Whereas when the Oyl of Vitriol was excited by a convenient heat which was not faint it corroded the Mercury into a fine white Calx or powder which by the affusion of fair water would be presently turn'd into a yellowish Calx of the colour and nature of a Turbith I remember also that having for trials sake dissolv'd in a weak Spirit of Salt a fourth part of its weight of fine Crystals of Nitre we found that it would not in the cold at least during a good while that we waited for its operation dissolve Leaf-gold but when the Menstruum was a little heated at the fire the Solution proceeded readily enough And in some cases though the external heat be but small yet there may intervene a brisk heat and much cooperate in the dissolution of a Body as for instance of Quick-silver in Aqua Fortis For it is no prodigy to find that when a full proportion of that fluid Metal has been taken the Solution though at first altogether liquid and as to sense uniform comes to have after a while a good quantity of coagulated or crystalliz'd matter at the bottom of which the cause may be that in the very act of Corrosion there is excited an intense degree of heat which conferring a new degree of agitation to the Menstruum makes it dissolve a good deal more than afterwards when the Conflict is over it is able to keep up EXPER. IV. WE have observed also that Agitation does in some cases so much promote the Dissolutive power of Saline bodies that though they be not reduc'd to that subrilty of parts to which a strong Distillation brings them yet they may in their grosser and cruder form have the power to work on Metals as I elsewhere shew that by barely boiling some Solutions of Salts of a convenient structure as Nitre Sal Armoniac c. with foliated Gold Silver c. we have corroded these Metals and can dissolve some others And by boiling crude Copper in Filings with Sublimate and common water we were able in no long time to make a Solution of the Metal EXPER. V. SOmetimes also so languid an Agitation as that which seems but sufficient to keep a Liquor in the state of fluidity may suffice to give some dry bodies a corroding power which they could not otherwise exercise as in the way of writing ones name or a Motto upon the blade of a knife with common Sublimate For if having very thinly overlaid which side you please with Bees-wax you write with a bodkin or some pointed thing upon it the Wax being thereby removed from the strokes made by the sharp body 't is easie to etch with Sublimate since you need but strew the powder of it upon the place bared of the Wax and wet it well with meer common water for strong Vinegar is not necessary For after a while all the parts of the blade that should not be fretted being protected by the Case or Film of Wax the Sublimate will corrode onely where way has been made for it by the bodkin and the Letters will be more or less deeply ingraven or rather etch'd according to the time the Sublimate is suffer'd to lye on And if you aim onely at a legible impression a few minutes of an hour as four or five may serve the turn EXPER. VI. THis brings into my mind an Observation I have sometimes had occasion to make that I found more useful than common and it is That divers Bodies whether distill'd or not distill'd that are not thought capable of dissolving other Bodies because in moderate degrees of heat they will not work on them may yet by intense degrees of heat be brought to be fit Solvents for them To which purpose I remember that having a distill'd Liquor which was rather sweet to the taste than either acid lixiviate or urinous though for that reason it seem'd unfit to work on Pearls and accordingly did not dissolve them in a considerable time wherein they were kept with it in a more than ordinarily warm digestion yet the Glass being for many hours amounting perhaps to some days kept in such an heat of sand as made the Liquor boil we had a Dissolution of Pearls that uniting with the Menstruum made it a very valuable Liquor And though the Solvents of crude Gold wont to be employed by Chymists are generally distill'd Liquors that are acid and in the lately mention'd Solvent made of crude Salts and common water Acidity seem'd to be the predominant quality which makes the use of Solutions made in Aqua Regia c. suspected by many Physicians and Chymists yet fitly chosen Alcalizate Bodies themselves as repugnant as they use to be to Acids without the help of any Liquor will be enabled by a melting Fire in no long time to penetrate and tear asunder the parts even of crude Gold so that it may afterwards be easily taken up in Liquors that are not acid or even by water it self EXPER. VII THe Tract about Salt-peter that gave occasion to these Annotations may furnish us with an eminent Instance of the Production of Solvents For though pure Salt-peter it self when dissolv'd in water is not observ'd to be a Menstruum for the Solution of the Metals hereafter to be named or so much as of Coral it self yet when by a convenient Distillation its parts are split if I may so speak and by Attrition or other Mechanical ways of working on them reduc'd to the shapes of Acid and Alcalizate Salts it then affords two sorts of Menstruums of very differing natures which betwixt them dissolve or corrode a great number and variety of Bodies as the Spirit of Nitre without addition is a Solvent for most Metals as Silver Mercury Copper Lead c. and also divers Mineral Bodies as Tin glass Spelter Lapis Calaminaris c. and the fixed Salt of Nitre operates upon Sulphureous Minerals as common Sulphur Antimony and divers other Bodies of which I elsewhere make mention EXPER. VIII BY the former Trials it has appear'd that the increase of Motion in the more penetrating Corpusoles of a Liquor contributes much to its Solutive power and I shall now adde that the Shape and Size which are Mechanical Affections and sometimes also the Solidity of the same Corpuscles does eminently concur to qualifie a Liquor to dissolve this or that particular body Of this even some of the more familiar practices of Chymists may supply us with Instances For there is no account so probable as may be given upon this supposition why Aqua Fortis which will dissolve Silver without medling with Gold should by the addition of a fourth part of its weight of Sal Armoniac be turn'd into Aqua Regia which without medling with Silver will dissolve Gold But there is no necessity of having recourse to so gross and compounded a Body as Sal Armoniac to enable Aqua Fortis to dissolve Gold For the Spirit of common Salt alone being mingled in a
due proportion will suffice for that purpose Which by the way shews that the Volatile Salt of Urine and Soot that concur to the making up of Sal Armoniac are not necessary to the dissolution of Gold for which a Solvent may be made with Aqua Fortis and crude Sea-salt I might adde that the Mechanical affections of a Menstruum may have such an interest in its dissolutive power that even Mineral or Metalline Corpuscles may become useful Ingredients of it though perhaps it be a distill'd Liquor as might be illustrated by the Operations of some compounded Solvents such as is the Oyl of Antimony made by repeated Rectifications of what Chymists call its Butter which whatever some say to the contrary does much abound in Antimonial Substance EXPER. IX BUt I shall return to our Aqua Regia because the mention I had occasion to make of that Solvent brought into my mind what I devis'd to make it probable that a smaller change than one would lightly imagine of the bulk shape or solidity of the Corpuscles of a Menstruum may make it fit to dissolve a Body it would not work on before And this I the rather attempted because the warier sort of Chymists themselves are very shye of the inward use or preparations made of Gold by the help of Aqua Fortis because of the odious stink they find and the venenosity they suspect in that corrosive Menstruum Whereas Spirit of Salt we look upon as a much more innocent Liquor whereof if it be but diluted with fair water or any ordinary drink a good Dose may be safely given inwardly though it have not wrought upon Gold or any other body to take off its acrimony But whether or no this prove of any great use in Physick wherein perhaps if any quantity of Gold be to be dissolved a greater proportion of Spirit of Nitre would be needed the success will not be unfit to be mention'd in reference to what we were saying of Solvents For whereas we find not that our Spirit of Salt here in England will at all dissolve crude Gold we found that by putting some Leaf-gold into a convenient quantity of good Spirit of Salt when we had dropt-in Spirit of Nitre shaking the Glass at each drop till we perceived that the mixture was just able in a moderate heat to dissolve the Gold we found that we had been oblig'd to employ but after the rate of twelve drops of the latter Liquor to an ounce of the former so that supposing each of these drops to weigh a grain the fortieth part of Spirit of Nitre being added served to turn the Spirit of Salt into a kind of Aqua Regia But to know the proportion otherwise than by ghess we weigh'd six other drops of the same Spirit of Salt and found them to amount not fully to three grains and an half Whence it appeared that we added but about a seventieth part of the Nitrous Spirit to that of Salt The Experiments that have been hitherto recited relate chiefly to the Production of Corrosive Menstruums and therefore I shall now adde an account of a couple of Trials that I made manifestly to lessen or quite to destroy Corrosiveness in Liquors very conspicuous for that quality EXPER. X. WHereas one of the most corrosive Menstruums that is yet known is Oyl of Vitriol which will fret in pieces both divers Metals and Minerals and a great number and variety of animal and vegetable bodies yet if you digest with it for a while onely an equal weight of highly rectified Spirit of Wine and afterwards distill the mixture very warily for else the Experiment may very easily miscarry you may obtain a pretty deal of Liquor not corrosive at all and the remaining substance will be reduc'd partly into a Liquor which though acid is not more so than one part of good Oyl of Vitriol will make ten times as much common water by being well mingled with it and partly into a dry substance that has scarce any taste at all much less a corrosive one EXPER. XI ANd though good Aqua Fortis be the most generally employed of corrosive Menstruums as being capable of dissolving or corroding not onely many Minerals as Tin-glass Antimony Zinke c. but all Metals except Gold for though it make not a permanent Solution of crude Tin it quickly frets the parts asunder and reduces it to an immalleable substance yet to shew how much the power of corroding may be taken away by changing the Mechanical Texture of a Menstruum even without seeming to destroy the fretting Salts I practis'd and communicated to divers Virtuosi the following Experiment elsewhere mentioned to other purposes We took equal parts of good Aqua Fortis and highly dephlegm'd Spirit of Wine and having mingled them warily and by degrees without which caution the Operation may prove dangerous we united them by two or three Distillations of the whole mixture which afterwards we found not to have the least fretting taste and to be so deprived of its corrosive nature that it would not work upon Silver though by Precipitation or otherwise reduc'd to very small parts nay it would scarce sensibly work in a good while on Filings of Copper or upon other bodies which meer Vinegar or perhaps Rhenish wine will corrode Nay I remember that with another Spirit that was not Urinous and afterwards with Alkool of Wine we shew'd a more surprizing Specimen of the power of either destroying or debilitating the Corrosiveness of a Menstruum and checking its Operation For having caused a piece of Copper plate to be put into one ounce of Aqua Fortis when this Liquor was eagerly working upon the Metal I caus'd an ounce of the Alkool of Wine or the other Spirit to be poured which it should warily be upon the agitated mixture whose effervescence at the first instant seemed to be much increased but presently after was checked and the Corrosiveness of the Menstruum being speedily disabled or corrected the remaining Copper was left undissolved at the bottom Nor are these the onely acid Menstruums that I have many years since been able to correct by such a way For I applied it to others as Spirit of Nitre and even Aqua Regis it self but it has not an equal operation upon all and least of all as far as I can remember upon Spirit of Salt as on the other side strong Spirit of Nitre was the Menstruum upon which its effects were the most satisfactory Most of the Chymists pretend that the Solutions of bodies are perform'd by a certain Cognation and Sympathy between the Menstruum and the body it is to work upon And it is not to be denied that in divers Instances there is as it were a Consanguinity between the Menstruum and the body to be dissolved as when Sulphur is dissolved by Oyls whether exprest or distill'd But yet as the opinion is generally proposed I cannot acquiesce in it partly because there are divers Solutions and other
nature of the things and Helmont's Writings have been lately alledg'd against their Hypothesis I consider how slight accounts they are wont to give us even of the familiar Phaenomena of Corrosive Liquors For if for example you ask a vulgar Chymist why Aqua fortis dissolves Silver and Copper 't is great odds but he will tell you 't is because of the abundance of fretting Salt that is in it and has a cognation with the Salts of the Metal And if you ask him why Spirit of Salt dissolves Copper he will tell you 't is for the same reason and yet if you put Spirit of Salt though very strong to Aqua fortis this Liquor will not dissolve Silver because upon the mixture the Liquors acquire a new Gonstitution as to the Saline Particles by vertue of which the mixture will dissolve instead of Silver Gold Whence we may argue against the Chymists that the Inability of this compounded Liquor to work on Silver does not proceed from its being weaken'd by the Spirit of Salt as well because according to them Gold is far the more compact metal of the two and requires a more potent Menstruum to work upon it as because this same compounded Liquor will readily dissolve Copper And to the same purpose with this Experiment I should alledge divers others if I thought this the fittest place wherein I could propose them SECT II. About the Mechanicall Origine of CORROSIBILITY COrrosibility being the quality that answers Corrosiveness he that has taken notice of the Advertisement I formerly gave about my use of the Term Corrosiveness in these Notes may easily judge in what sense I employ the name of the other Quality which whether you will stile it Opposite or Conjugate for want of a better word I call Corrosibility This Corrosibility of Bodies is as well as their Corrosiveness a Relative thing as we see that Gold for instance will not be dissolved by Aqua fortis but will by Aqua Regis whereas Silver is not soluble by the latter of these Menstruums but is by the former And this relative Affection on whose account a Body comes to be corrodible by a Menstruum seems to consist chiefly in three things which all of them depend upon Mechanical Principles Of these Qualifications the first is that the Body to be corroded be furnish'd with Pores of such a bigness and figure that the Corpuscles of the Solvent may enter them and yet not be much agitated in them without giving brisk knocks or shakes to the solid parts that make up the walls if I may so call them of the Pores And 't is for want of this condition that Glass is penetrated in a multitude of places but not dissipated or dissolv'd by the incident beams of Light which permeate its Pores without any considerable resistance and though the Pores and Commissures of a Body were less minute and capable of letting in some grosser Corpuscles yet if these were for want of solidity or rigidness too flexible or were of a figure incongruous to that of the Pores they should enter the Dissolution would not insue as it happens when pure Spirit of Wine is in the cold put upon Salt of Tartar or when Aqua fortis is put upon powder of Sulphur The second Qualification of a Corrodible Body is that its consistent Corpuscles be of such a Bulk and Solidity as does not render them uncapable of being disjoyn'd by the action of the insinuating corpuscles of the Menstruum Agreeable to this and the former Observation is the practice of Chymists who oftentimes when they would have a Body to be wrought on by a Menstruum otherwise too weak for it in its crude estate dispose it to receive the action of the Menstruum by previously opening it as they speak that is by enlarging the Pores making a comminution of the Corpuscles or weakening their Cohesion And we see that divers Bodies are brought by fit preparations to be resoluble in Liquors that would not work on them before Thus as was lately noted Lime-stone by Calcination becomes in part dissoluble in water and some Metalline Calces will be so wrought on by Solvents as they would not be by the same Agents if the preparation of the Metalline or other Body had not given them a new Disposition Thus though crude Tartar especially in lumps is very slowly and difficultly dissoluble in cold water yet when 't is burnt it may be presently dissolved in that Liquor and thus though the Filings and the Calx of Silver will not be at all dissolv'd by common water or Spirit of Wine yet if by the interposition of the Saline Particles of Aqua Fortis the Lunar Corpuscles be so disjoyn'd and suffer such a comminution as they do in Crystals of Lune the Metal thus prepared and brought with its Saline Additament into a new Texture will easily enough dissolve not onely in water but as I have tried in well rectified Spirit of Wine And the like Solubility I have found in the Crystals of Lead made with Spirit of Verdigrease or good distill'd Vinegar and in those of Copper made with Aqua Fortis The last Disposition to Corrosibility consists in such a cohesion of the parts whereof a Body is made up as is not too strict to be superable by the action of the Menstruum This Condition though of kin to the former is yet somewhat differing from it since a body may consist of parts either bulky or solid which yet may touch one another in such small portions of their Surfaces as to be much more easily dissociable than the minute or less solid parts of another Body whose contact is more full and close and so their Cohesion more strict By what has been said it may seem probable that as I formerly intimated the Corrosibility of Bodies is but a Mechanical Relation resulting from the Mechanical Affectious and Contexture of its parts as they intercept Pores of such sizes and figures as make them congruous to those of the Corpuscles of the Menstruum that are to pierce between them and disjoyn them That the Quality that disposes the body it affects to be dissolv'd by Corrosive and other Menstruums does as hath been declared in many cases depend upon the Mechanical Texture and Affections of the body in reference to the Menstruum that is to work upon it may be made very probable by what we are in due place to deliver concerning the Pores of Bodies and Figures of Corpuscles But yet in compliance with the design of these Notes and agreeably to my custom on other Subjects I shall subjoyn a few Experiments on this occasion also EXPER. I. IF we put highly rectified Spirit of Wine upon crude Sulphur or even Flowers of Sulphur the Liquor will lie quietly thereon especially in the cold for many hours and days without making any visible Solution of it and if such exactly dephlegmed Spirit were put on very dry Salt of Tartar the Salt would lie in an
first with Spirit of Vinegar and then of Wine after the long and laborious way prescribed by Basilius and Zwelfer but easily and expeditiously by a simple Distillation of crude Verdigrease of the better sort For when you have with this Liquor being if there be need once rectified dissolv'd as much good Salt of Tartar as 't will take up in the cold if you draw off the Menstruum ad siccitatem the remaining dry Salt will be manifestly alter'd in Texture even to the eye and will readily enough in high rectified Spirit of Wine afford a Solution which I have found considerable in order to divers uses that concern not our present Discourse EXPER. VI. TO the Consideration of the Followers of Helmont I shall recommend an Experiment of that famous Chymist's which seems to sute exceeding well with the Doctrine propos'd in this Section For he tells us that if by a subtle Menstruum to which he ascribes that power Quicksilver be devested or depriv'd of its external Sulphur as he terms it all the rest of the fluid Metal which he wittily enough stiles the Kernel of Mercury will be no longer corrosible by it So that upon this Supposition though common Quicksilver be observ'd to be so obnoxious to Aqua Fortis that the same quantity of that Liquor will dissolve more of it than of any other Metal yet if by the deprivation of some portion of it the latent Texture of the Metal be alter'd though not that I remember the visible appearance of it the Body that was before so easily dissolved by Aqua Fortis ceases to be at all dissoluble by it EXPER. VII AS for those Chymists of differing Sects that agree in giving credit to the strange things that are affirm'd of the Operations of the Alkahest we may in favour of our Doctrine urge them with what is deliver'd by Helmont where he asserts that all solid Bodies as Stones Minerals and Metals themselves by having this Liquor duly abstracted or distill'd off from them may be changed into Salt equiponderant to the respective bodies whereon the Menstruum was put So that supposing the Alkahest to be totally abstracted as it seems very probable to be since the weight of the body whence 't was drawn off is not alter'd what other change than of Texture can be reasonably imagin'd to have been made in the transmuted bodies and yet divers of them as Flints Rubies Saphyrs Gold Silver c. that were insoluble before some of them in any known Menstruums and others in any but Corrosive Liquors come to be capable of being dissolv'd in common water EXPER. VIII 'T Is a remarkable Phaenomenon that suits very well with our opinion about the interest of Mechanical Principles in the Corrosive Power of Menstruums and the Corrosibility of bodies that we produc'd by the following Experiment This we purposely made to shew after how differing manners the same body may be dissolv'd by two Menstruums whose minute parts are very differingly constituted and agitated For whereas 't is known that if we put large grains of Sea-salt into common water they will be dissolved therein calmly and silently without any appearance of conflict If we put such grains of Salt into good Oyl of Vitriol that Liquor will fall suriously upon them and produce for a good while a hissing noise with fumes and a great store of bubbles as if a potent Menstruum were corroding some stubborn metal or mineral And this Experiment I the rather mention because it may be of use to us on divers other occasions For else 't is not the onely though it be the remarkablest that I made to the same purpose EXPER. IX FOr whereas Aqua Fortis or Aqua Regis being pour'd upon Filings of Copper will work upon them with much noise and ebullition I have tried that good Spirit of Sal Armoniac or Urine being put upon the like Filings and left there without stopping the Glass will quickly begin to work on them and quietly dissolve them almost as water dissolves Sugar To which may be added that even with Oyl of Turpentine I have though but slowly dissolved crude Copper and the Experiment seemed to favour our Conjecture the more because having tried it several times it appear'd that common unrectified Oyl would perform the Solution much quicker than that which was purified and subtiliz'd by rectification which though more subtle and penetrant yet was it seems on that account less fit to dissolve the Metal than the grosser Oyl whose particles might be more solid or more advantageously shap'd or on some other Mechanical account better qualified for the purpose EXPER. X. TAke good Silver and having dissolv'd it in Aqua Fortis precipitate it with a sufficient quantity of good Spirit of Salt then having wash'd the Calx which will be very white with common water and dried it well melt it with a moderate fire into a fusible Mass which will be very much of the nature of what Chymists call Cornu Lunae and which they make by precipitating dissolv'd Silver with a bare Solution of common Salt made in common water And whereas both Spirit of Salt and Silver dissolv'd in Aqua Fortis will each of them apart readily dissolve in simple water our Luna Cornea not onely will not do so but is so indispos'd to Dissolution that I remember I have kept it in Digestion some in Aqua fortis and some in Aqua Regia and that for a good while and in no very faint degree of heat without being able to dissolve it like a Metal the Menstruums having indeed ting'd themselves upon it but left the Composition undissolv'd at the bottom With this Instance of which sort more might be afforded by Chymical Precipitations I shall conclude what I design'd to offer at present about the Corrosibility of Bodies as it may be consider'd in a more general way For as to the Disposition that Particular Bodies have of being dissolved in or of resisting Determinate Liquors it were much easier for me to enlarge upon that Subject than it was to provide the Instances above recited And these are not so few but that 't is hop'd they may suffice to make it probable that in the Relation betwixt a Solvent and the Body it is to work upon that which depends upon the Mechanical affections of one or both is much to be consider'd and has a great interest in the operations of one of the bodies upon the other FINIS OF THE MECHANICAL CAUSES OF CHYMICAL PRECIPITATION By the Honourable ROBERT BOYLE Esq Fellow of the R. Society LONDON Printed by E. Flesher for R. Davis Bookseller in Oxford 1675. Advertisement THough I shall not deny that in Grammatical strictness Precipitation should be reckoned among Chymical Operations not Qualities yet I did not much scruple to insert the following Discourse among the Notes about Particular Qualities because many if not most of the Phaenomena mentioned in the ensuing Essay may be considered as depending some of them
upon a power that certain bodies have to cause Precipitation and some upon such a Disposition to be struck down by others as may if men please be called Precipitability And so these differing Affections may with at least tolerable Congruity be referred to those that we have elsewhere stiled Chymical Qualities But though I hope I may in these few Lines have said enough concerning the name given to these Attributes yet perhaps it will be found in time that the things themselves may deserve a larger Discourse than my little leasure would allow them For that is not a causeless Intimation of the Importance of the subject wherewith I conclude the following Tract since besides that many more Instances might have been particularly referred to the Heads treated of in the Insuing Essay there are improper kinds of Precipitation besides those mentioned in the former part of the Discourse to which one may not incongruously refer divers of the Phaenomena of Nature as well in the greater as in the lesser world whereof either no Causes at all or but improper ones are wont to be given And besides the simple Spirits and Salts usually employed by Chymists there are many compounded and decompounded bodies not only factitious but natural and some such as one would scarce suspect that may in congruous subjects produce such Precipitations as I speak of And the Phaenomena and Consequents of such operations may in divers cases prove conducive both to the Discovery of Physical Causes and the Production of useful effects though the particularizing of such Phaenomena do rather belong to a History of Precipitations than to such a Discourse as that which follows wherein I proposed not so much to deliver the latent Mysteries as to investigate the Mechanical Causes of Precipitation OF THE MECHANICAL CAUSES OF CHYMICAL PRECIPITATION CHAP. I. BY Precipitation is here meant such an agitation or motion of a heterogeneous liquor as in no long time makes the parts of it subside and that usually in the form of a powder or other consistent body As on many occasions Chymists call the substance that is made to fall to the bottom of the liquor the Precipitate so for brevity sake we shall call the body that is put into the liquor to procure that subsiding the Precipitant as also that which is to be struck down the Precipitable substance or matter and the liquor wherein it swims before the separation the Menstruum or Solvent When a hasty fall of a heterogeneous body is procured by a Precipitant the Operation is called Precipitation in the proper or strict sense But when the separation is made without any such addition or the substance separated from the fluid part of the liquor instead of subsiding emerges then the word is used in a more comprehensive but less proper acceptation As for the Causes of Precipitation the very name it self in its Chymical sense having been scarce heard of in the Peripatetic Schools it is not to be expected that they should have given an account of the Reasons of the thing And 't is like that those few Aristotelians that have by their converse with the laboratories or writings of Chymists taken notice of this Operation would according to their custom on such occasions have recourse for the explication of it to some secret sympathy or antipathy between the bodies whose action and reaction intervenes in this Operation But if this be the way proposed of accounting for it I shall quickly have occasion to say somewhat to it in considering the ways proposed by the Chymists who were wont to refer Precipitation either as is most usual to a sympathy betwixt the Precipitating body and the Menstruum which makes the Solvent run to the embraces of the Precipitant and so let fall the particles of the body sustained before or with others to a great antipathy or contrariety between the acid salt of the Menstruum and the fixed salt of the Oil or solution of calcined Tartar which is the most general and usual Precipitant they imploy But I see not how either of these causes will either reach to all the Phaenomena that have been exhibited or give a true account even of some of those to which it seems applicable For first in Precipitations wherein what they call a sympathy between the liquors is supposed to produce the effect this admired sympathy does not in my apprehension evince such a mysterious occult Quality as is presumed but rather consists in a greater congruity as to bigness shape motion and pores of the minute parts between the Menstruum and the Precipitant than between the same Solvent and the body it kept before dissolved And though this sympathy rightly explained may be allowed to have an interest in some such Precipitations as let fall the dissolved body in its pristine nature and form and only reduced into minute powder yet I find not that in the generality of Precipitations this Doctrine will hold For in some that we have made of Gold and Silver in proper Menstruums after the subsiding matter had been well washed and dried several Precipitates of Gold made some with oil of Tartar which abounds with a fixed salt and is the usual Precipitant and some with an Urinous Spirit which works by Vertue of a salt highly fugitive or Volatile I found the powder to exceed the weight of the Gold and Silver I had put to dissolve and the Eye it self sufficiently discovers such Precipitates not to be meer metalline powders but Compositions whose consisting not as hath been by some body suspected of the combined Salts alone but of the metalline parts also may be strongly concluded not only from the ponderousness of divers of them in reference to their bulk but also manifestly from the reduction of true malleable metals from several of them CHAP. II. THE other Chymical way of explicating Precipitations may in a right sence be made use of by a Naturalist on some particular occasions But I think it much too narrow and defective as 't is in a general way proposed to be fit to be acquiesced in For first 't is plain that 't is not only Salt of Tartar and other fixed Alcalies that precipitate most bodies that are dissolved in acid Menstruums as in making of Aurum fulminans oil of Tartar precipitates the Gold out of Aqua Regis But acid liquors themselves do on many occasions no less powerfully precipitate metals and other bodies out of one another Thus spirit of Salt as I have often tried precipitates Silver out of Aqua fortis The corrosive Spirit of Nitre copiously precipitates that white powder whereof they make Bezoardicum Minerale Spirit or oil of Sulphur made by a glass-bell precipitates Corals Pearls c. dissolved in Spirit of Vinegar as is known to many Chymists who now use this Oleum Sulphuris per Campanam to make the Magistery of Pearls c. for which vulgar Chymists imploy Oleum Tartari per deliquium I have sometimes made a Menstruum wherein
though there were both Acid and Alcalizate Salts yet I did not find that either acid Spirits or oil of Tartar or even Spirit of Urine would precipitate the dissolved substances And I have observed both that Salts of a contrary nature will precipitate bodies out of the same Menstruum as not only Salt of Tartar but Sea-salt being dissolved will precipitate each other and each of them apart will precipitate Silver out of Aqua fortis and that even where there is a confessed contrariety betwixt two liquors it may be so ordered that neither of them shall precipitate what is dissolved by the other of which I shall have occasion to give ere long a remarkable instance But it will best appear that the abovementioned Theories of the Peripateticks and Chymists are at least insufficient to solve the Phaenomena many of which were probably not known to most of them and perhaps not weigh'd by any if we proceed to observe the Mechanical ways by which Precipitations may be accounted for whereof I shall at present propose some Number and say somewhat of each of them apart not that I think all of them to be equally important and comprehensive or that I absolutely deny that any one of them may be reduced to some of the other but that I think it may better elucidate the subject to treat of them severally when I shall have premised that I wouldnot thence infer that though for the most part Nature does principally effect Precipitations by one or other of these ways yet in divers cases she may not imploy two or more of them about performing the operation To precipitate the Corpuscles of a metal out of a Menstruum wherein being once throughly dissolved it would of it self continue in that state the two general ways that the nature of the thing seems to suggest to him that considers it are either to add to the weight or bulk of the dissolved Corpuscles and thereby render them unfit to accompany the particles of the Menstruum in their motions or to weaken the sustaining power of the Menstruum and thereby disable it to keep the metalline particles swimming any longer which falling of the deserted parts of the metal or other bodie does oftentimes the more easily insue because in many cases when the sustaining particles of the Menstruum come to be too much weakned that proves an occasion to the metalline Corpuscles disturbed in the former motion that kept them separate to make occursions and coalitions among themselves and their fall becomes the effect though not equally so of both ways of Precipitation as on the other side there are several occasions on which the same Precipitant that brings the swimming particles of the metal to stick to one another does likewise by mortifying or disabling the saline Spirits or other parts of the solvent weaken the sustaining power of that liquor CHAP. III. TO descend now to the distinct Considerations about these two ways The first of the most genera Causes of Precipitation is such a Cohaesion procured by the Precipitant in the solution as makes the compounded corpuscles or at least the associated particles of the dissolved body too heavy to be sustained or too bulky to be kept in a state of fluidity by the liquor That in many Precipitations there is made a coalition betwixt the small parts of the Precipitant and those of the dissolved metal or other body and frequently also with the saline spirits of the Menstruum may be easily shewn by the weight of the Precipitate which though carefully washed and dryed often surpasses and sometimes very considerably that of your crude metal that was dissolved of which we lately gave an instance in Aurum fulminans and precipitated Silver we may yet give a more conspicuous one in that which Chymists call Luna Cornea For if having dissolved Silver in good Aqua fortis you Precipitate it with the solution of Sea-salt in fair water and from the very white Precipitate wash the loose adhering salts the remaining powder being dryed and slowly melted will look much less like a metalline body than like a piece of horn whence also it takes its name so considerable is the additament of the saline to the metalline particles And that part of such additaments is retained may not only be found by weighing but in divers cases may be argued from what is obvious to the Eye as if you dissolve Mercury in Aqua fortis and into the philtrated solution drop spirit of Salt or salt-water or an urinous spirit as of Sal Armoniac you will have a very white Precipitate but if instead of any of these you drop-in deliquated salt of Tartar your Precipitate will be of a brick or orange colour From which experiment and some others I would gladly take a rise to perswade Chymists and Physitians that 't is not so indifferent as those seem to think who look on Precipitation butas a kind of Comminution by what means the precipitation is performed For by reason of the strict adhesion of divers saline particles of the precipitant and the solvent the precipitated body notwithstanding all the wonted ablutions may have its qualities much diversified by those of the particles of the liquors when these are fitted to stick very fast to it Which last words I add because though that sometimes happens yet it does not always there being a geater difference than every body takes notice of between Precipitations as you will be induced to think if you precipitate the solution of Silver with Copper with spirit of Sal Armoniac with salt water with oil of Tartar with quick-silver with crude Tartar and with Zink And in the lately proposed Example you will think it probable that 't is not all one whether to dissolved Mercury or Silver you imploy the subtile distilled Spirits of Salt or the gross body whether in a dry form or barely dissolved in common water And thus much of the Conduciveness of weight to the striking down the Corpuscles of a dissolved Body That also the Bulk of a body may very much contribute to make it sink or swim in a liquor appears by obvious instances Thus Salt or Sugar being put into water either in lumps or even in powder that is but gross falls at first to the bottom and lies there notwithstanding the Air that may be intercepted between its parts or externally adhere to it But when by the infinuating action of the water it is dissolved into minute particles these are carried up and down with those of the liquor and subside not The like happens when a piece of silver is cast into Aqua fortis and in many other cases On the other side I have several times observed that some bodies that had long swam in a Menstruum whilst their minute parts were kept from convening in it did afterwards by the coalition of many of those particles into bodies of a visible bulk coagulate and subside though sometimes to hinder the evaporation of
the Menstruum the vessels were kept stopt Of this I elsewhere mention divers examples and particularly in urinous and animal spirits well dephlegm'd I have found that after all had for a considerable time continued in the form of a perfect liquor and as to sense homogeneous store of solid corpuscles convening together setled at the bottom of the glasses in the form of saline Crystals Having also long kept a very red solution of Sulphur first unlock'd as they speak made with highly rectified spirit of urine I observed that at length the Sulphureous particles making little concretions between themselves totally subsided and left the liquor almost devoid of tincture By which you may see that 't was not impertinent to mention as I lately did among the subordinate causes of Precipitation the associating of the particles of a dissolved body with one another Of which I elsewhere give a notable Example in the shining powder that I obtained from Gold dissolved in a peculiar Menstruum without any Precipitant by the coalition of the metalline particles to which a tract of time gave opportunity to meet and adhere in a convenient manner If in what the Chymists call Presipitate per se the Mercury be indeed brought to lose its fluidity and become a powder without being compounded with any additional body which doubt I elsewhere state and discourse of it will afford us a notable instance to prove that the coalitions of particles into clusters of the self same matter will render them unfit for the motion requisite to fluidity For in this odd precipitation by fire wherein the same Menstruum is both the Liquor and the Precipitate being not all made at once the Corpuscles that first disclose themselves by their redness are rejected by those of the Mercury that yet remains fluid as unable to accompany them in the motions that belong to Mercury as such CHAP. IV. BEfore I dismiss that way of Precipitating that depends upon the unwieldiness which the Precipitant gives to the body it is to strike down it may not be impertinent especially in reference to the foregoing part of this Paper to consider that perhaps in divers cases the Corpuscles of a dissolved body may be made unfit to be any longer sustained in the Menstruum though the Precipitant adds very little to their bulk or at least much more to their specific weight than to it For I have elsewere shewn that in divers solutions made of bodys by acid Menstruums there are either generated or extricated many small Aerial particles and it will be easily granted that these may be small enough to be detained in the pores of the liquor and be invisible there if we consider what a multitude of aerial and formerly imperceptible bubbles is afforded by common water in our Pneumatical Receivers when the incumbent air that before pressed the liquor is pumpt out And if the Corpuscles of the dissolved body have any little Cavities or pores fit to lodge Aerial particles or have asperous surfaces between whose prominent parts the generated air may conveniently lie in such cases I say these Invisible bubbles may be lookt upon as making with the solid Corpuscles they adhered to little aggregates much lighter in specie than the Corpuscles themselves would be and consequently if the Precipitant consist of particles of such a size and shape as are fit to expel these little bubbles and lodge themselves in the cavities possessed by them before there will be produced new aggregates composed of the Corpuscles of the dissolved body and the particles of the Precipitant which aggregates though they do take up very little or perhaps not at all more room takeing that word in a popular sense than those whereof the Aerial bubbles made a part will yet be Specifically heavier than the former Aggregates were and may thereby overcome the sustaining power of the Menstruum One thing more may be fit to be taken notice of before we pass on further namely that 't is upon the score of the Specific gravity of a body and not barely upon the action of the Precipitant that an aggregate or a Convention of particles does rather fall to the bottom than rise to the top For though the Agents that procured the Coalition make the cluster of particles become of a bulk too unwieldy to continue in the liquor as parts of it yet if each of them be lighter in specie than an equal bulk of the Menstruum or if they so convene as to intercept a sufficient number of little bubbles or aerial Corpuscles between them and so become lighter than as much of the Menstruum as they take up the room of they will not be precipitated but emerge as may be seen in the Preparation of those Magisteries of Vegetables I elswhere mention where some deeply colour'd plants being made to tinge plentifully the Lixivium they are boyled in are afterwards by the addition of Alum made to curdle as it were into coloured Concretions which being totally or in part too big to swim as they did before they conven'd and too light in comparison of the Menstruum to subfide emerge to the top and float there An easier and neater Example to the same purpose I remember I shewed by dissolving Camphire in highly rectified spirit of Wine 'till the solution was very strong For though the Camphire when put in Lumps into the spirit sunk to the bottom of it yet when good store of water a liquor somewhat heavier in Specie than Camphire was poured upon the solution the Camphire quickly concreted and returned to its own nature and within a while emerged to the top of the mingled liquors and floated there These particulars I was willing to mention here that I might give an instance or two of those precipitations that I formerly spake of as improperly so called And here I must not decline taking notice of a Phaenomenon that sometimes occurs in Precipitations and at first sight may seem contrary to our Doctrine about them For now and then it happens that after some drops of the Precipitant have begun a Precipitation at the top or bottom of the Solvent one shakes the vessel that the Precipitant may be the sooner diffused through the other liquor but then they are quickly surprized to find that instead of hastning the compleat Precipitation the matter already precipitated disappears and the solvent returns to be clear or as to sense as uniform as it was before the Precipitant was put into it Bu this Phaenomenon does not at all cross our Theory For when this happens though that part of the Solvent to which the Precipitant reaches is disabled for Reasons mentioned in this Discourse to support the dissolved body yet this quantity of the Precipitant is but small in proportion to the whole bulk of the solvent And therefore when the agitation of the vessel disperses the clusters of loosly concreted particles through the whole liquor which is seldom so exactly proportioned to the body it
was to work on as to be but just strong enough to dissolve it that greater part of the Liquor to which before the shaking of the vessel the Precipitant did not reach may well be lookt upon as a fresh Menstruum which is able to mortifie or overpower the small quantity of the Precipitant that is mingled with it and so to destroy its late operation on the body dissolved by which means the solution returns as to sense to its former state Which may be illustrated by a not unpleasant Experiment I remember I have long since made by precipitating a brick-coloured powder out of a strong solution of Sublimate made in fair water For this subsiding matter being laid to dry in the Philter by which 't was separated from the water would retain a deep but somewhat dirty colour and if then putting it into the bottom of a wine glass I poured upon it either clear oil of Vitriol or some other strong acid Menstruum the Alcalizat particles being disabled and swallowed up by some of the acid ones of the Menstruum the other acid ones would so readily dissolve the residue of the powder that in a trice the colour of it would disappear and the whole mixture be reduced into a clear Liquor without any sediment at the bottom Thus much may suffice at present about the first general way of Precipitating Bodies out of the Liquors they swam in CHAP. V. THE other of the two principal ways by which Precipitations may be effected is the disabling of the Solvent to sustain the dissolved body There may be many instances wherein this second way of effecting Precipitations may be associated by Nature with the first way formerly proposed but notwithstanding the cases wherein Nature may as I formerly noted imploy both the ways therein yet in most cases they sufficiently differ in regard that in the former way the subsiding of the dissolved body is chiefly if not only caused by the additional weight as well as action of the external Precipitant whereas in most of the instances of the later way the effect is produced either without salt of Tartar or any such Precipitant or by some other quality of the Precipitant more than by its weight or at least besides the weight it adds Though I forget not that I lately gave an example of a shining powder of Gold that fell to the bottom of a Menstruum without the help of an External Precipitant But that was done so slowly that it may be disputed whether it were a true Precipitation and I alledged it not as such but to shew that the increased bulk of Particles may make them unfit to swim in Menstruums wherein they swam whilst they were more minute And the like answer may be accommodated to the Precipitate per se newly mentioned This premised I proceed now to observe that the general way I last proposed contains in it several subordinate wayes that are more particular of which I shall now mention the chief that occur to me and though but briefly illustrate each of them by examples And first a Precipitation may be made if the saline or other dissolving particles of the Menstruum are mortified or rendred unfit for their former function by particles of a Precipitant that are of a contrary nature Thus Gold and some other minerals being dissolved in Aqua Regis will be precipitated with spirit of urine and other such liquors abounding with volatile and salino-sulphureous Corpuscles upon whose account it is that they act whence these salts themselves though cast into a Menstruum in a dry form will serve to make the like Precipitations And I the rather on this occasion mention Urinous spirits than Salt of Tartar because those volatile particles add much less of weight to the little Concretions which compose the Precipitated powder Upon instances of this kind many of the modern Chymists have built that Antipathy betwixt the Salts of the solvent and those of the Menstruum to which they ascribe almost all Precipitations But against this I have represented something already and shall partly now and partly in the sequel of this discourse add some farther reasons of my not being satisfied with this Doctrine For besides that 't is insufficient to reach many of the Phaenomena of Precipitations as will ere long be shown and besides that 't is not easie to make out that there is any real antipathy betwixt inanimate bodies I consider 1. That some of those Menstruums to which this Antipathy is attributed do after a short commotion whereby they are disposed to make convenient occursions and coalitions amicably unite into concretions participating of both the Ingredients as I have somewhere shewn by an Example purposely devis'd to make this out to do which I dropped a clear solution of fixed Nitre instead of the usual one of common salt upon a solution of silver in Aqua-fortis For the saline particles of the Solvent and those of the Precipitant will as I have elsewhere recirecited for the most part friendly unite into such Crystals of Nitre for the main as they were obtained from And though this notion of the Chymists if well explained be applicable to far more instances than the proposers of it seemed to have thought on and may be made good use of in Practice yet I take it to be such as is not true Universally and where it is true ought to be explicated according to Mechanical Principles For if the particles of the Menstruum and those of the Precipitant be so framed that upon the action of the one upon the other there will be produced Corpuscles too big and unwieldy to continue in the state of fludity there will insue a Precipitation But if the constitution of the corpuscles of the Precipitating and of the Dissolved body be such that the Precipitant also it self is fit to be a Menstruum to dissolve that body in then though there be an union of the Salts of the Precipitant and the metal or other Solutum and perhaps of the solvent too yet a Precipitation will not necessarily follow though the saline particles of the two liquors seemed by the heat and ebullition excited between them upon their meeting to exercise a great and mutual antipathy To satisfie some Ingenious men about this particular I dissolved Zink or Speltar in a certain urinous spirit for there are more than one that may serve the turn and then put to it a convenient quantity of a proper acid spirit but though there would be a manifest conflict thereby occasioned betwixt the two liquors yet the speltar remained dissolved in the mixture And I remember that for the same purpose I devised another Experiment which is somewhat more easie and more clear I dissolved Copper calcined perse or even crude in strong spirit of salt for unless it be such it will not be so proper and having put to it by degrees a good quantity of spirit of Sal-Armoniac or fermented Urine though there would be a
put among themselves or with those of the additament into a complicated state or intangled contexture This being the usual and principal way of producing Fixity we shall dwell somewhat the longer upon it and give Instances of several degrees of Fixation For though they do not produce that quality in the strictest acceptation of the word Fixity yet 't is usefull in our present inquiry to take notice by what means that volatility comes to be gradually abated since that may facilitate our understanding how the Volatility of a body comes to be totally abated and consequently the body to be fixt CHAP. IV. AND first we find that a fixt additament if its parts be conveniently shaped may easily give a degree of fixity to a very volatile body Thus Spirit of Nitre that will of it self easily enough fly away in the Air having its saline particles associated with those of fixt Nitre or salt of Tartar will with the Alkaly compose a salt of a Nitrous nature which will endure to be melted in a Crucible without being deprived even of its Spirits And I have found that the spirits of Nitre that abound in Aqua fortis being concoagulated with the Silver they corrode though one would not expect that such subtile Corpuscles should stick fast to so compact and solid a body as Silver yet Crystalls produced by their Coalition being put into a Retort may be kept a pretty while in fusion before the metal will let go the Nitrous spirits When we poured Oil of Vitriol upon the Calx of Vitriol though many Phlegmatick and other Sulphureous particles were driven away by the excited Heat yet the saline parts that combined with the fixt ones of the Colcothar stuck fast enough to them not to be easily driven away And if Oil of Vitriol be in a due proportion dropt upon Salt of Tartar there results a Tartarum vitriolatum wherein the acid and alkalizate parts cohere so strongly that 't is not an ordinary degree of fire will be able to disjoyn them Insomuch that divers Chymists have though very erroniously thought this compounded Salt to be indestructible But a less heavy liquour than the ponderous Oil of Vitriol may by an Alkaly be more strongly detained than that Oil it self experience having assured me that Spirit of Salt being dropt to satiety upon a fixt Alkaly I used either that of Nitre or of Tartar there would be made so strict an union that having without additaments distilled the resulting salt with a strong and lasting fire it appeared not at all considerably to be wrought upon and was not so much as melted But 't is not the bare Mixture or Commistion of Volatile particles with Fixt ones yea though the former be predominant in quantity that will suffice to elevate the latter For unlesse the figures of the latter be congruous and fitted to fasten to the other the volatile parts will fly away in the Heat and leave the rest as fixt as before as when sand or ashes are wetted or drenched with water they quickly part with that water without parting with any degree of their Fixity But on the other side it is not always necessary that the body which is fitted to destroy or much abate the volatility of another substance should be it self fixt For if there be a skilful or lucky coaptation of the figures of the particles of both the bodies these particles may take such hold of one another as to compose corpuscles that will neither by reason of their strict union be divided by Heat nor by reason of their resulting grossness be elevated even by a strong fire or at least by such a degree of Heat as would have sufficed to raise more indisposed bodies than either of the separate Ingredients of the mixture This observation if duly made out does so much favour our Doctrine about the Mechanical Origine of Fixation and may be of such use not onely to Chymists in some of their operations but to Philosophers in assigning the causes of divers Phaenomena of Nature that it may be worth while to exemplifie it by some Instances The first whereof I shall take from an usual practice of the Chymists themselves which I the rather doe to let you see that such known Experiments are too often over-looked by them that make them but yet may hint or confirm Theories to those that reflect on them The Instance I here speak of is that which is afforded by the vulgar Preparation of Bezoardicum Minerale For though the rectified Butter or Oil of Antimony and the Spirit of Nitre that are put together to make this white Praecipitate are both of them distilled liquours yet the copious powder that results from their Union is by that Union of volatile parts so far fixt that after they have edulcorated it with water they prescribe the calcining of it in a Crucible for five or six hours which operation it could not bear unless it had attained to a considerable fixation This discourse supposes with the generality of Chymists that the addition of a due quantity of spirit of Nitre is necessary to be employed in making the Bezoardicum Minerale But if it be a true Observation which is attributed to the Learned Guntherus Billichius but which I had no Furnace at hand to examine when I heard of it if I say it be true that a Bezoardicum Minerale may be obtained without spirit of Nitre barely by a slow evaporation made in a Glasse-dish of the more fugitive parts of the Oil of Antimony this Instance will not indeed be proper in this place but yet will belong to the second of the foregoing ways of introducing Fixity I proceed now to alleage other particulars in favour of the above-mentioned Observation If you take strong Spirit of Salt that when the Glass is unstopt will smoak of it self in the cold air and satiate it with the volatile Spirit of Urine the superfluous moisture being abstracted you will obtain by this preparation which you may remember I long since communicated to you and divers other Virtusi a compounded Salt scarce if at all distinguishable from Sal Armoniac and which will not as the Salts it consists of will doe before their coalition easily fly up of it self into the air but will require a not despicable degree of fire to sublime it Of these semivolatile Compositions of Salt I have made and elsewhere mentioned others which I shall not here repeat but passe on to other Instances pertinent to our present design I lately mentioned that the Volatility of the spirits of Nitre may be very much abated by bringing them to coagulate into Crystalls with particles of corroded Silver but I shall now add that I guessed and by trial found that these Nitrous spirits may be made much more fixt by the addition of the Spirit of Salt which if it be good will of it self smoak in the Air. For having dissolved a convenient quantity of Crystalls of Silver in distilled water and