THE NEW METHOD OF Fortification As Practised by Monsieur de VAUBAN Engineer General of FRANCE WITH AN EXPLICATION Of all Terms appertaining to that ART Made English LONDON Printed for Abel Swall at the Unicorn at the West-End of St. Paul's Church-Yard 1691. To His GRACE THE DUKE of ORMOND May it please Your Grace THE General Complaint of the want of Books of Fortification in our English Tongue has encouraged me to Translate â—â—at of Monsieur Vauban To which I â—as invited by the almost Universal Applause 〈◊〉 has received from the most competent â—â—dges Nothing could have emboldned me 〈◊〉 the Presumption of this Address but the â—â—od and Welfare of my Native Countrey 〈◊〉 proposing your Grace to the Imitation of our Nobility and Gentry which seems to be the only Means for this Kingdom to recover its Ancient Glory I doubt not but that brave Example which your Grace continually sets to the whole Nation will inspire the Men of Quality to come up to it as near as possible Which if they had always done Vauban might without any great Detriment to us have been confin'd to the Territories of his Master That your Grace may ever prosper and receive the Honours due to so great Merits as it is the greatest Good can be wished you so it is no less the unâ—eigned Desire of May it please your Grace Your Grace's most Obedient and most humble Servant ABEL SWALL THE PREFACE THis little Tract which was chiefly design'd by the Ingenious Author for the Use and Benefit of young Gentlemen and others addicted to the Study of this part of the Mathematicks who have not leisure or opportunity to read over the vast Systems of Voluminous Writers has deservedly obtain'd so great a Repute among the Curious that it is Translated into several Languages It contains an exact Explication of all the Terms that are attributed to Mathematical Bodies and in general all that is necessary for the Theory and Practice of a good Geometrician Moreover therein is exhibited the true Mensuration of Heights Lengths Planes Solids and Concaves as also the Science call'd The Transmutation of Bodies which is the Subject of the first Part. In the Second are explain'd the Rules that are observ'd by the French Engineers at this day in raising theâ—r Works and at the same time are produced the different Sentiments of the French among themselves as to this Matter it is likewise shewn wherein their manner of Operation differs from that of the Germans and other Nations Lastly The most clear and accurate Method of Fortiâ—ication is plainly taught The Word Geometry is derived from the Greek 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 importing to measure the Earth so that Geometry with respect to its Etymology is nothing else but the Art of measuring Land yet in a larger and more proper Sense it is applied to all sorts of Dimensions As for the Original of this Science it is indeed very uncertan and it is believed by many that the Egyptians were the â—irst Inventers thereof For in regard that the River Nile does every Year overflow the Country of Egypt those Inundations which generally overthrew and confounded all the Land-Marks oblig'd the Inhabitants to devise certain Measures by the means whereof they might be able to distinguish and adjust the Limits of their respective Grounds from those of their Neighbours when the Waters were withdrawn And this Opinion is not altogether to be rejected especially if we consider that Moses is generally reputed to have given them the first Rudiments of this Art However since there were not very many Men who applied themselves to the Study of gooâ— Literature in those early Ages of the World The Mathematicks and Geometry in particular were as it were lock'd up within the Breast of some few Learned and Skilful Artists until the Time of Thales who first publickly professed them in Greece nevertheless the Grecians were not very diligent in promoting and improving these Noble Sciences and only taught them privately neither was there any one that undertook to shew the Usefulness and Necessity of this kind of Learning until Euclid wrote his Elements which gave occasion to the Publishing of a great Number of excellent Treatises on this Subject that are now extant An Advertisement to the Book-Binder 1. CAre must be taken not to cut the Blank Paper on which the Plates are wrought off by reason that the Figures must be so placed as to â—old out of the Book 2. There are Eight Figures which must be placed at the End of the Treatise of Geometry immediately after the Table they are marked thus Geom. Pl. 1 2 3 4 5 6 7 8. 3. The other Figures belong to the Fortiâ—ication and are to be placed at the End of the Book and set in order as they are marked A B C D E F G H I K L M N O P Q R S T V W X. A TABLE of the Matters contained in this Treatise of FORTIFICATION BOOK I. CHAP. I. §. I. OF the Definition of Military Architecture p. 1 §. II. Of the Original of Fortification p. 2 §. III. Of the Parts of Fortification p. 3 §. IV. Of the Division of Military Architecture p 4. CHAP. II. Of the Parts of a Fortress and its Angles ib. CHAP. III. Of the Terms of the Measures p. 6 CHAP. IV. Of the Names and Terms made use of as well in attacking as in the Defence of Places alphabetically set down p. 7 BOOK II. CHAP. I. Of the Maxims of Fortification p. 21 CHAP. II. Of the Situation of Places p. 25 §. I. Of the Advantages and Disadvantages of a Fortress situated on a Mountain p. 25 26 §. II. Of the Advantages and Disadvantages of a Marshy or Fenny Situation p. 27. §. III. Of the Advantages and Disadvantages of a Place encompassed round with Water ibid. §. IV. Of the Advantages and Disadvantages of Places situated upon an open Rising Ground p. 28 §. V. Of the Side of a Mountain p. 29 §. VI. Of a Valley ibid. §. VII Of the Advantages and Disadvantages of a Place situated on the side of a great River ibid. CHAP. III. Of the Quality of the Earth p. 30 CHAP. IV. Of Provision and other Neceâ—â—aries p. 32 BOOK III. CHAP. I. §. I. How to describe any Polygon within a given Circle p. 33 §. II. How to make a Scale p. 34 CHAP. II. How to make the Draught of a Square as also the Orillon and the Hollow Tower p. 35 CHAP. III. Of the Structure of the Body of the Place of the Square p. 38 CHAP. IV. Of the Structure of the Half-Moon before the Curtain of the Square p. 40 CHAP. V. §. 1. Of the Structure of the Ravelin before the Curtain ibid. §. II. To make a Ravelin with Cuneâ—teâ— p. 41 §. III. Of a Ravelin with Counter-guards ibid. §. IV. To make a Ravelin to be placed at the Entrances into Places p. 42 CHAP. VI. To make a Horn-Work before the
the Place is by so much the stronger and consequently better because gains more Sideâ— VI. The Angle of the Bastion must never be greateâ— than 100 Degrees nor less than 60 for being bigger the Face cannot be defended as it ought to be and being less it is not able to resist the Injury of the Weather or the Efforts of the Mines and Cannon See Chap. 1. Sect. 4. of Book IV. VII The greatest Angles are best to fortify VIII The Angle of the Curtain ought never to be less than 90 Degrees nor greater than 110 because if it be larger 't is too much subject to the view of the Enemy See Chap. 1. Sect. 5. of Book IV. IX The great Demi-Gorges are to be preferred before the small ones as well because there is more space to retrench in as because one may make retiring Flanks which adds very much to the strength of the place X. Great Flanks are best XI The Face ought to be never less than the half of the Curtain if it be not in an Irregular Fortificationâ— XII The Faces of the Bastion ought to be defended by the small Shot of the opposite Flanks XIII The shortest Faces are best because they are not so subject to be attacked as when they come ouâ— a great way in the Country See Chap. â— of Book IV. XIV The Curtain ought never to be shorter than 60 Fathoms which is 360 foot English nor longer than 100 if it be not in an Irregular Fortification XV. The Line of Defence must not be of greater length than 120 or 125 fathoms because a Musquet can carry no farther to do execution Holdman goes contrary to this Axiom when he says that it may be 150 fathoms and likewise George Pascha who believes it may be 136 fathoms long XVI The Taluâ— or Level ought by no means to be forced or streightened but oâ—ght to have sloap enough that the Ground or Earth may settle of itself XVII Large and deep Trenches are to be preferred before those that are narrow and hollow or large and less deep because the Enemy will find more difficulty to get over the first sort See Chap. 10. of Book I. XVIII Dry Trenches are to be esteemed before those that are full of Water especially in great Places where Sallies Retreats and Succors are necessary XIX Trenches full of Water that cannot easily be drained ought to be preferred before those that are dry in small Fortresses where Sallies Retreats and Succors are not so necessary XX. The Outworks ought always to be lower than the Body of the Place and those that are at the greatest distance ought to be the lowest CHAP. II. Of the Situation of Places AS it is very rarely permitted to make choice of that space of Ground which is to be fortified but on the contrary the Place is almost always determined whether we design to repair an old Fortification or surround any Town with Bastions and other kind of Works or whether we are to make ourselves Masters of the Passage of a River of any strait Place or an Eminence that is of advantage to command the flat Country or an Island in a River or of one or more jettings out of Land into the Sea for the making a Port and lastly for several other Uses the recital whereof would be too tedious It is necessary upon these Accounts to understand what kind of Situations are best for the Erecting a strong Hold and to know the Opinions of others concerning this Matter I. What are the Advantages of a Fortress situated upon a Mountain 1. This Fortification is not easily Ruined by Mines 2. The Enemy will be at a great deal of difficulty to bring their Machines to batter down this Fortification 3. Those of the place may discover the Enemy at a great distance and so hinder them from making their Approaches nearer 4. The Horse or Batteries of the Enemy which are planted either on plain or rising Ground can no ways do any damage to this Fortification it being always lower 5. Upon an Eminence the Air is always more healthy than in Vallies or lower Places 6. The Enemy will but very rarely be able to take such a Place by Assault What are the Disadvantages of a Fortress built upon a Rock 1. They commonly want Water in such a place 2. It is difficult to bring thither Materials Provisions â—nd other Ammunition 3. These Fortifications are for the most part not very durable having only a sandy or gravelly Earth for Foundation 4. Places so situated are not to be succoured but with great difficulty 5â— Such a Place cannot well be defended becauâ—e what is done by the Cannon from top to bottom is but of little consequence 6. Sallies are there very dangerous especially if they be at any distance from the Counterscarps 7. These Fortifications are almost always Irregular Advertisement It is to be observed that these kind of Situations are good for Cittadels Castles and other small Forts in order to command the Country thereabouts II. The Advantages of a Marshy or Fenny Situation 1. The Enemy cannot come near it without danger of being lost 2. This Fortification is not easily blown up 3. These Places may be fortified for little Charge 4. They have there no need of a great Garison The Disadvantages of a Marshy Situation 1. It is almost impossible to relieve it 2. It must be strengthened with Piles driven in 3. Sallies thence are commonly unsuccessful 4. The Air is there always unhealthy which is the occasion of frequent Distempers because the Water there is always corrupted 5. These Places may be attacked without any great loss of Men provided they stay till the Frosts III. The Advantages of a Place encompassed round with Water 1. It cannot be undermined 2. There is no occasion for any great Worksâ— 3. The Enemy cannot always discharge their Cannon with any certainty because the Water abates much of their force 4. The Besieged may very easily set fire to the Enemies Shiâ—ping 5. â—he Naval Army is too much exposed to the â—iew of the Artillery of the Place The Disadvantages of a Place surrounded with Water 1. The Enâ—my may â—asily stop their Provision and hinder their Succors 2. Boats alone are sufficient to attack such a place and so there is no occasion for Horse 3. These Places are more subject to Diseases than otheâ—s Advertisement We may affirm that these Places that are encompassed all round with Water which cannot be quite drained or at least with great difficulty are the best notwithstanding because they are as it were fortified by Nature IV. The Advantages of Places situated upon an open Rising Ground 1. There is great Plenty of good Earth 2. They are never there in want of Water 3. Almost all these Places are commonly Regular 4. They have there Earth enough to make Retrenchments in case the Enemy make their Attacks with great fury 5. The Enemy had need to have two or three Armies if they would
intercept the Provision and Ammunition coming to those of the Place from all Parts The Disadvantages of Places erected upon Rising Ground 1. The good Soil that there is about such a Place serves only for the Enemy to make Retrenchmen◠〈◊〉 Batteries Approaches Redoubts and other Works from whence they may do great Damage to the Besieged 2. The Enemy may form their Camp as those of the Place did their Fortification that is to say they may give it a Regular Figure and encompass it with a good Trench and a good Rampart 3. The Ground is very good to make Mines under such a place 4. The Enemy may seize all the Fruits growing about these places Advertisement These Places however are best because those of the place will take double the Advantage that the Enemy can have V. The side of a Mountain is a very ill place to fortify and it must be avoided as much as may be because the top of the Mountain almost always commands the Place within VI. The Valley is is no good place to fortify because the Enemy may discover them from the top of the Mountain VII The Advantages of Places situated on the Sides of any Great River 1. You may bring thither by Water whatsoever is necessary for Building and for the Soldiers 2. You may fortify the Circumference after the Regular manner or at least very near it The side towards the Water is fortified with small Charge 3. It may be easily Relieved 4. Earth is there very plentiful for repairing thâ— Works and for making Retrenchments 5. You may there make Sluces to put all the Country thereabouts under Water 6. They never want there any Water 7. The Enemy must have a great many Troops to â—ay Siege to such a Place by reason of the distance of the Qâ—arters 8. If it be attacked only by Land nothing hinders but that the Besieged may pass the River at pleasure and receive Succors by Boats 9. If it be attacked both by Land and by Water there must be two great Armies which will be very Chargeable The Disadvantages of Places situated on the Sides of a Great River 1. The River serves the Enemy for transporting whatsoever is necessary for a Siege 2. The Enemy may cast up great heaps of Earth to Command the Place 3. The Enemy may easily shelter themselves from the Firing of the Besieged having great plenty of Earth Advertisement 'T is not to be denied but that these Places are to be preferred before any of those that we have now mentioned in case they are Masters of the Pass by which the Provision and Ammunition is to come in CHAP. III. Of the Quality of the Earth WHen you have once made choice of a Place for the erecting a Fortress before you Engage yourself in so expensive an undertaking you must examine the Quality of the Earth and consider whether it be Good or Bad For there are very Advantageous Situations the Earth whereof is good for nothing and on the contrary there are Ill Situations that have a very good Soil but they lie subject to be Commanded after such a rate that it would be great folly to settle there As may be evident by the following Observations Sect. I. MOuntains commonly have a stony Ground which is the worst of all as well because it will not stick together as because the Parapers made thereof are good for nothing But if you are compelled to fortify in such a place you must make choice of the best Veins of Earth to make the Parapet and cause it to be brought from elsewhere 'T is true this sort of Earth is of some advantage in that the Besiegers will find it difficult to cover themselves in their Approaches for want of good Earth Sect. II. THE Gravelly or Sandy Earth is likewise very bad by reason that it wants a binding Quality being always apt to tumble down when you are forced to make use of this you must mix some good Earth therewith or some old Dung and the Ramparts must be well lined with Stonâ—s or Bricks and the Parapets with Turfs Sect. III. THE Marshy Ground is better than the two former sorts although generally 't is not very good because when it comes to dry being raised into Ramparts and Parapets it is subject to fall to pieces besides 't is difficult to find Earth enough about a Marshy place for raising Ramparts Parapets and Glacis of a reasonable height and moreover the Foundation of these Works must be always strengthened with Piles But if there bâ— a necessity of raising Fortifications in these places it must be during the Heats that so the Earth may have the greater Consistence Sect. IV. THE best kind of Earth for Fortifying is that which they call Fat or Fertile Ground because 't is pliable and you are not obliged to strengthen the Foundation with Piles nor to line the Ramparts unless you will CHAP. IV. Of Provision and other Necessaries SEing a Place cannot be able to endure a long Siege if it has not wherewithal to make resistance therefore there must be Provision made of whatsoever is necessary for a Soldier under which Head is to be understood Money to pay the Troops Meal Corn Hay Wine Beer Brandy Butter Salt Wood Powder Lead Match Bullets Cannon or Great Guns Musquets Pikes Sulphur Pitch Brimstone Palisadoes Chevaux de Frise Hand-Mills Horse-Mills and Wind-Mills that so if the Enemy should cut off the Water they might not be without something to Grind their Corn. A good Commander will take care of all this An able Physician Chirurgeon and Apothecary are there likewise very necessary To these there might be added some other Things requisite in order to keep the Soldiers in good heart A NEW TREATISE OF Fortification BOOK III. CHAP. I. Sect. 1. How to inscribe any Polygon within a Circle givâ—nâ— THIS Problem is commonly treated of in Geometry Nevertheless because it is impossible to work on a Regular Fortification on Paper without knowing before-hand how to inscribe Regular Figures in a Circle given or taken at pleasure we shall at present discourse something thereof 1. Divide the Diameter of your Circle given A. B. into as many equal parts as you would give sides to your Figure For example into Five 2. Draw the Diameter A. B. and make with this distance of points A. B. 〈◊〉 Aâ—â—â—es to intersect in C. 3. Draw from the Point C. through the second Part which is mark'd by the Point E. of the said Diameter a Riâ—ht Liâ—â— tâ—ll it toâ—ch the â—ircumfeâ—ence 〈◊〉 beâ—oâ—â— the Diâ—meâ—â—r in â— 4. This distance from the Intersection to the first â—â—int A. of the Diameter will be always one side of the Polygon demanded See the Plate B. Fig. 2. Seâ—t â— How to make a Scale AS every thing is to be done by a Scale you must know likewise the manâ—er how it is made which is as follows 1. Divide a Line into 10 equal parts and one of these to shew the