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Garrison Service in any part of the World out of the United Kingdom. Active Service, implying duty in the Field against an Enemy.

FORGE. A portable forge, including every material for Smith's Work, is attached to the Train of Artillery, and to Regiments of Cavalry.

The forge Carts are issued in the latter instance from the Ordnance Magazines as an Ordnance Store; but they are to be kept in repair twelve years, out of the allowance granted for farriery.

FORLORN HOPE. A body, or party, of Officers and Men, generally Volunteers, who are detached for the purpose of leading the attack of an Army when Storming a Fortress; from this circumstance and the great danger which they have to encounter from being the first to receive the whole fire of the Enemy, the detachment has received this name. Promotion is usually bestowed on the

survivors.

FORMATION. The drawing up, or arrangement, of Troops according to prescribed rules.

FORT MAJOR. Officers employed as Fort Majors, if under the rank of Captains, take rank and precedence as the junior Captains in the Garrisons in which they are

serving. Effective Field Officers cannot hold the situation of Fort Major, without resigning their Regimental Appointment.

FORTS, are a species of Field Works constructed to secure a post of importance, either to form points d'appui to the wings of an Army or to command the resources of a district. They are divided into two classes; Star forts and Bastioned forts, generally separated from the exterior ground by a ditch and covered way. The former present a series of projecting and re-entering angles; these salient angles should not be less than 60°, nor should the re-entering angles be less than 90°. A Star fort is seldom constructed on a Polygon of more than eight sides, as the trouble which would then become necessary for its construction, would be fully as great as that requisite for a square Bastioned fort, without attaining the superior advantages afforded by the latter. One general rule for

tracing Star forts is, to construct an equilateral triangle on each of the sides of the Polygon on which the fort is to be erected. This method, however, is not so applicable to square and pentagonal Star forts, in the construction of which the flanked angle is usually obtained by means of a perpendicular and lines of defence.

The tracing of Bastioned forts is nearly the same as in Permanent fortification, and as their construction requires much care, precaution, and labour, they ought to be reserved for cases requiring a strong defence. The lines of

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FORTIFICATION.

defence should not exceed eighty toises, otherwise they will be too long for the range of musquetry, and the flanked angles will consequently be very ineffectually protected by the fire from the flanks.

FORTRESS. A strong hold, a fortified place.

FORTIFICATION. Defensive Fortification, is the art of surrounding a place by works so disposed as to render it capable of a lasting defence against a besieging army. Offensive Fortification, comprehends the various works employed in conducting a siege.

Natural Fortification, consists of those obstacles which Nature affords to retard the progress of an enemy, such are woods, deep ravines, rocks, marshes, &c.; while,

Artificial Fortification, is that which is raised by human ingenuity to aid the advantages of the ground, or supply its deficiencies. It is divided into Permanent and Field Fortification.

Permanent Fortification, intended for the defence of towns, frontiers, and seaports, is constructed in time of peace and of durable materials, while Field Fortification being raised only for the temporary purpose of protecting troops in the field, its materials are those afforded by local circumstances and a limited time. In a work like the present, it cannot be expected that we should enter at large into the various systems invented by Engineers for the perfect defence of towns; it will be sufficient therefore to give a general outline of a Fortification, referring the reader to those works on the subject, mentioned in the introductory Address. It is a study highly essential to Officers of every rank, and requiring the careful perusal of volumes specially devoted to the explanation of its principles. The most celebrated systems of Fortification were those of Marshal Vauban, but they contained many serious defects; and Cormontaingne, the most successful of modern Engineers, having devoted his attention to the various plans which existed before his time, finally decided on the first system of Vauban as the most susceptible of improvement. The method which he adopted for this purpose was well deserving the name of a new system, but its author modestly contented himself with calling it “An improved tracing of the First System of Vauban by Cormontaingne ", a name by which it is now generally known.

The Town is supposed to be enclosed by a Polygon, upon which the enceinte, or line of the principal works, is constructed. The sides of this Polygon never exceed

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180 toises in length, being the range of the Artillery usually mounted on the ramparts of a Fortification; they are bisected by perpendicular lines, the length of which is proportioned to the number of sides of which the Polygon is composed, being one eighth of the length of the exterior side for a square, one seventh for a pentagon, and one sixth for a hexagon, or any other polygon. Through the inner extremities of these perpendiculars, lines, called the Lines of Defence, are drawn to the angles of the Polygon. At each of these angles, Bastions are then constructed, the faces of which are a portion of the Lines of Defence, to which their flanks are drawn perpendicularly. The length of the faces is made from fifty to sixty toises, in order to afford ample space in the interior of the Bastion.

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The extremities of the flanks being connected by a line of work called the Curtain, completes the enceinte, or Body of the Place. Upon this tracing is placed a broad Rampart surrounding the place, on the exterior edge of which an earthen Parapet is raised. The object of the Rampart is to give the troops and artillery a sufficient command over the exterior country. The height and thickness of the Parapet is such as to protect and effectually screen the defenders from the direct fire of the Enemy. This height has been limited to seven feet and a half, and as the parapet is exposed to the fire of the heaviest artillery, it is made proportionably broad to withstand its effects, and this object is obtained by giving it a thickness of eighteen feet of soft earth, properly turfed on all its sides. The upper surface of the parapet, called the superior slope, is inclined towards the country so as to enable the fire of the musquetry to defend the Covered way. The parapet is terminated externally by the exterior slope, which prevents the earth from crumbling and falling into the ditch, and towards the town by the interior slope, the base of which is made equal to one third of its height, in order to enable the troops to fire over it without constraint. The Banquette is placed behind this parapet, and the clear space left on the rampart, called its terrepleine, has been limited to about eighteen or twenty toises, terminated towards the town by a slope of 45°. This enceinte is surrounded by the Main Ditch, the Counterscarp of which is directed to the inner angle of the shoulder, formed by the meeting of the crests of the parapets of the flank and face of the bastion. The Ditch is generally made from fifteen to eighteen toises wide, in order that the Enemy in crossing it may be exposed for a considerable time to the fire of the defenders. With respect to its depth it must be so regulated as to prevent the assailants from being able to see, and breach the foot of the revêtement of the escarp, besides rendering an escalade difficult. These objects are best accomplished, when its depth below the surface of the ground is made nearly equal to the command of the works above it. The sides of the ditch are faced with a wall of masonry, called a revêtement. The Demilune is placed in advance of the curtain and is surrounded by a ditch, whose depth is diminished to several feet from that of the

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