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.

CHAP I. Of the Maxims of Fortification.

SInce it is impossible to build a Fortress, without having considered before-hand what Reasons there are to induce an Enginier to do it after such a manner, that there is no great matter to be ob∣jected against it; there are some certain Maxims established, according to which, when a Fortification is raised, there can be but little said against its Advantages to those that are within; as you may easily examine it your self by the following Obser∣vations.

I.

All the Parts which are to enclose a space of Ground, ought to be flank'd, that is to say, view'd on every side, that so there may be no shelter about the place where the Enemy may lodge himself, but what may be discovered by those within, not only from the front, but from the sides, and even from behind, if it be possible.

II.

Whatsoever encloses a durable Fortification, must be either Flank, Face, or Curtain, and built after such a manner, that the first Discharges of the Cannon may not be able to pierce its thickness.

III.

Regular Fortification is much to be preferred be••ore that which is Irregular.

IV.

It is impossible to fortify a Triangle after the Regular way, because the Angle of the Gorge is always less by 90 Degrees.

V.

The straighter the Angle of the Center is, the Place is by so much the stronger, and consequently better, because gains more Side••.

VI.

The Angle of the Bastion must never be greate•• 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, 'tis 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 Fortification••

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 sub∣ject to be attacked, as when they come ou•• a great way in the Country. See Chap. ••. 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 far∣ther 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 fa∣thoms long.

XVI.

The Talu•• or Level ought by no means to be forced or streightened, but o••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.