FOR (se

small mugs, and angular polygons. The,engineers of the present day assert withconfidence, that the chief security to bederived in works that are supported bybastions, must depend upon cross andreverse firing directedagainst the enemy’slodgments on the glacis. Large halt-moons are made, not only for the pur-pose of covering the curtains and theflanks of bastions, but principally toobtain a reverse filing, which effectuallyprevents the enemy from maintaininghis ground on the glacis of a bastion,before he has taken the two collaterallialf-moons. See a particular exami-nation of this method, and a comparisonof it with Vauban ’s, or the, customaryone, by Mr. Glenie.

M. Minno, Baron of Coehorn, whowas general of artillery in the Dutch service, lieutenant-general of infantry,director-general of all the fortified placesbelonging to the United Provinces , andgovernor of Plunders and all the for-tresses that lay along the Scheldt, hasbeen justly esteemed for his extensiveknowledge in the art of fortifying places,lie was contemporary with Vauban . Thisintelligent and sagacious officer beingthoroughly convinced, that, however ex-pensively the rampart of a town may beconstructed, it could not long sustainthe shock of heavy ordnance, inventedthree different systems, by which hethrows so many obstacles in the way of abesieging enemy, that although the placebe not in reality rendered impregnable,it is nevertheless so far secured as toSnake its conquest a business of consi-derable hazard and expense. We musthowever acknowledge, that the threemethods which have been pointed outby this Dutch general, can only suitplaces and grounds that are nearly on alevel with the surface of the water; thatis to say of 3, 4, or 5 feet; which cir-cumstance plainly indicates, that hisattention has been chiefly directed tothe soil and ground of the United Provinces ; so that his instructions arepeculiarly applicable to low and aquaticsituations. There is much skill dis-covered in his manner of treating thesubject, and considerable ingenuity inthe treatise he has published, whichcertainly contains several improvementsthat are exclusively his own. It wouldbe impossible to force a passage, or topenetrate into any of his works, withoutbeing exposed on all sides to the fire of

6 ) FOE.

the besieged, who are under cover, andfrom whose discharge of ordnance anilmusketry it is scarcely possible for anassailing enemy to secure himself. Hepublished his work before he had muchexperience, and did not follow' it infortifying Bergen-op-zoom .

Scheiter, a German writer, describestwo kinds of fortification, the great orthe superior , and the small or the infe-rior species. It has been erroneouslyand unjustly stated, that the celebratedVauban only copied after Scheiter, atNeuf Brisach.

Every man of the least knowledge orpenetration must see, that the wholesystem of that illustrious engineer dif-fers essentially from the author we havequoted.

Mr. Belidor has also delivered threemethods, all of which he applies to anoctagon of 200 toises.

In his first method the perpendicularto the exterior side is equal to 30 toises,the angle formed by the line of defenceand exterior side is very nearly equal to26° 33' 54", the flanked angle to 81° 52'12", and the outward flanking angle to120° 52' 12".

In this second method the perpendi-cular is equal to 55 toises, the angleformed by the line of defence, andexterior side is very nearly equal to 28°48' 39", the flanked angle to 77° 22' 42",and the outward flanking angle to 122°22' 42".

In his third method the perpendicularis equal to 40 toises, the angle formedby the line of defence, and exterior sideis very nearly equal to 21° 48' 5",' theflanked angle to 91° 23' 50", and theoutward flanking angle to 136° 23' 50".

The face of the bastion in the first andsecond of these methods is equal to 70toises, and in the third to 55 toises.

Scheiter also delivers three methods,which he distinguishes into great, meanandlittie, andin imitation ofCount Pagan,he makes the exterior side of the polygonin the great equal to 200 toises, in themean to 180, and the little to 160.

Simon Steam, a Fleming, wrote a bookon fortification ; in the second chapterof which he exemplifies his method ofconstruction on a hexagon. He con-structs outwards, and supposes eachside of the hexagon, from which hemakes his construction, to be equal to1000 feet. On each side and from eachextremity thereof he sets off 180 feet.