Part 28

DECAGON, in fortification, is a polygon figure, having 10 sides, and as many angles; and if all the sides are equal, and all the angles, it is called a regular decagon, and may be inscribed in a circle. The sides of a regular decagon are, in power and length, equal to the greatest segment of an hexagon inscribed in the same circle, and cut in extreme and mean proportion.

DECAGONE. _Fr._ See DECAGON.

_To_ DECAMP, to march an army or body of men from the ground where it before lay encamped. It also signifies to quit any place or position in an unexpected manner. See CAMP.

DECANUS, in Roman military history, an officer who presided over ten other officers, and was head of the contubernium, or serjeant of a file of Roman soldiers; hence our _Deacons_.

DECHARGEURS, _Fr._ are men appointed to attend the park of artillery, and to assist the non commissioned officers, &c. who are employed on that service. It is the duty of the former to keep a specific account of articles received and consumed, in order to enable the latter to furnish their officers with accurate statements.

_To_ DECIMATE, to divide any body of men into as many tenths as the aggregate number will afford, and to make them cast lots for the purpose of being punished.

DECIMATION, in Roman military history, a punishment indicted upon such soldiers as quitted their post, or behaved themselves cowardly in the field. The names of all the guilty were put into an urn or helmet, and as many were drawn out as made the tenth part of the whole number: the latter were put to the sword and the others saved.

DECIMER, _Fr._ See DECIMATE.

DECLARATION _of war_, a public proclamation made to the citizens, or subjects of a state, declaring them to be at war with any foreign power, and forbidding all and every one to aid or assist the common enemy, at their peril.

DECLIVITY, as opposed to acclivity, means a gradual inclination, or obliquity reckoned downwards.

DECOMPTE, _Fr._ signifies a liquidation, or balance, which from time to time was made in the old French service, between the captain of a company and each private soldier, for monies advanced, or in hand. In the British service every infantry soldier is settled with on the 24th day in each month. The cavalry is paid every second month. In the American army the soldiers are required to be paid every two months at least.

DECOUVERTE, _Aller à la découverte_, _Fr._ To patrole. In the old French service, the party ordered to perform this duty, when in a garrison, usually went three miles round the fortifications to pick up stragglers who could not account for themselves, and to secure spies, should any be lurking about.

_Aller à la_ DECOUVERTE, when applied to any party that is detached from the army, signifies to reconnoitre the enemy. Cavalry are usually employed upon this duty.

DECOY, a stratagem to carry off the enemy’s horses in a foraging party, or from the pasture; to execute which, you must be disguised, and mix on horseback in the pasture, or amongst the foragers on that side on which you propose to fly; you must then begin, by firing a few shots, which are to be answered by such of your party as are appointed to drive up the rear, and are posted at the opposite extremity of the pasture, or foraging ground; after which they are to gallop from their different stations towards the side fixed for the flight, shouting and firing all the way: the horses being thus alarmed, and provoked by the example of others, will break loose from the pickets, throw down their riders and the trusses, and setting up a gallop, will naturally direct their course to the same side; insomuch that, if the number of them was ever so great, you might lead them in that manner for several leagues together: when you are got into some road, bordered by a hedge, or ditch, you must stop as gently as possible; and without making any noise; the horses will then suffer themselves to be taken without any opposition. It is called in French _Haraux_; and marshal Saxe is the only author that mentions it.

DECOYED, an enemy is said to be decoyed when a small body of troops draws them into action, whilst the main body lies in ambush ready to act with the greatest effect.

DECURIO, in Roman military history, a commander of ten men in the army, or chief of a decury.

DECURY, ten Roman soldiers ranged under one chief, or leader, called the Decurio.

DEEP, troops are told off in ranks of two, or 3 deep, and on some occasions in 4 or more.

DEFAULTER. See DESERTER.

DEFEAT, the overthrow of an army.

DEFECTION. See MUTINY.

DEFENCE, in fortification, consists of all sorts of works that cover and defend the opposite posts; as flanks, parapets, casemates, and fausse-brays. It is almost impossible to fix the miner to the face of a bastion, till the defences of the opposite one are ruined; that is, till the parapet of its flank is beaten down, and the cannon, in all parts that can fire upon that face which is attacked, is dismounted. See FORTIFICATION.

_Active_ DEFENCE, generally considered, means every species of offensive operation which is resorted to by the besieged, to annoy the besiegers. Such for instance, is the discharge of heavy ordnance from the walls, the emission of shells, and the firing of musquetry. A mass of water may likewise be understood to mean active defence, provided it can be increased according to the exigency of the service, and be suddenly made to overflow the outworks, or entrenchments of the besieging enemy. Mines which are carried beyond the fortifications may likewise be included under this head.

_Passive_ DEFENCE is chiefly confined to inundations, and is effected by letting out water in such a manner, that the level ground which lies round a fortified town or place may be entirely overflowed and become an inert stagnant pool. Mere _submersion_ is, in fact, the distinguishing character of this species of defence, which does not afford any other movement than what naturally arises from the greater or lesser elevation of the waters, without the means of urging them beyond a given point.

_Distant_ DEFENCE, consists in being able to interrupt the enemy’s movements by circuitous inundations; to inundate, for instance, a bridge, when a convoy is passing, or to insulate batteries, the heads of saps or lodgments which have been made in the covert way is to act upon a distant defence. By this species of defence an enemy’s communications may be perpetually intercepted, and his approaches so obstructed as to force him to leave dangerous intervals.

See Belidor’s treatise on Hydraulic Architecture.

_Line of_ DEFENCE, represents the flight of a musquet ball from the place where the musqueteers stand, to scour the face of the bastion. It should never exceed the reach of a musquet. It is either fichant or razant: the first is when it is drawn from the angle of the curtain to the flanked angle; the last, when it is drawn from a point in the curtain, razing the face of the bastion.

_Line of_ DEFENCE is the distance between the salient angle of the bastion, and the opposite flank; that is, it is the face produced to the flank. See FORTIFICATION.

DEFENCE _of rivers_, in military affairs, is a vigorous effort to prevent the enemy from passing; to effect which, a careful and attentive officer will raise redoubts, and if necessary join curtains thereto: he will place them as near the banks as possible, observing to cut a trench through the ground at the windings of the river, which may be favorable to the enemy, and to place advanced redoubts there, to prevent his having any ground fit to form on, &c. See RIVERS.

_To be in a posture of_ DEFENCE, is to be prepared to oppose an enemy, whether in regard to redoubts, batteries, or in the open field.

_To_ DEFEND, to fortify, secure, or maintain a place or cause.

DEFENSE, _Fr._ See _Ligne de_ DEFENSE.

DEFENSE, _Fr._ _être en défense_, technically signifies to be in a state of defence, or able to resist. The French usually say: _Cette redoute est en défense_. This redoubt is in a state of defence.

DEFENSES _d’une place_, _Fr._ See DEFENCE in FORTIFICATION.

DEFENSIVE, serving to defend; in a state or posture of defence.

DEFENSIVE-_war_. See WAR.

DEFIANCE. See CHALLENGE.

DEFICIENT, wanting to complete, as when a regiment, troop, or company has not its prescribed number of men.

DEFILE, in military affairs, a strait narrow passage, or road, through which the troops cannot march, otherwise than by making a small front, and filing off; so that the enemy may take an opportunity to stop, or harrass their march, and to charge them with so much the more advantage, because the rear cannot come up to the relief of the front.

_To_ DEFILE, is to reduce divisions or platoons into a small front, in order to march through a defile; which is most conveniently done by quarter facing to either the right or left, and then covering to either right or left, and marching through by files, &c. It has been mentioned by a writer on military manœuvres, that defiling should be performed with rapidity, for this obvious reason, that a body of men which advances towards, or retires from an approaching enemy, may get into line, or into columns prepared for action, without loss of time. There may, however, be exceptions to this general rule. For instance, if the regiment is passing a bridge, either retreating or advancing, and the bridge is not firm, the pressure upon it must be as little as possible; because if it should break down, the regiment is suddenly separated, and the remainder may be cut to pieces. In passing a common defile the pace must be proportioned to the nature of the ground.

DEFILING _a lodgment_. See ENFILADE.

DEFORMER, _Fr._ in a military sense, signifies to break: as _déformer une colonne_, to break a column.

DEFY. See CHALLENGE.

DEGAST, _Fr._ the laying waste an enemy’s country, particularly in the neighborhood of a town which an army attempts to reduce by famine, or which refuses to pay military exactions.

DEGORGEOIR, _Fr._ a sort of steel pricker used in examining the touch-hole of a cannon; called a priming wire.

DEGRADATION, in a military life, the act of depriving an officer for ever of his commission, rank, dignity, or degree of honor; and taking away, at the same time, title, badge, and every other privilege of an officer.

DEGRADER, _Fr._ To degrade. The character of a soldier in France was formerly, and we presume still is, so scrupulously watched, that criminals were never delivered over to the charge of the civil power, or sent to be executed, without having been previously degraded; which was done in the following manner:

As soon as the serjeant of the company to which the culprit belonged, had received orders from the major of the regiment, to degrade and render him incapable of bearing arms; he accoutred him cap-a-pied, taking care to place his right hand upon the but-end of the musquet, while the soldier remained tied. He then repeated the following words: _finding thee unworthy to bear arms, we thus degrade thee_. “Te trouvant indigne de porter les armes, nous t’en dégradons.” He then drew the musquet from his arm backwards, took off his cross-belt, sword, &c. and finally gave him a kick upon the posteriors. After which the serjeant retired, and the executioner seized the criminal. See DRUM-OUT.

DEGRE. See DEGREE.

DEGREE. Though this term properly belongs to geometry, nevertheless it is frequently used both in fortification, and gunnery. Hence it will not be improper to state, that it is a division of a circle, including a 360th part of its circumference. Every circle is supposed to be divided into 360°, parts called degrees, and each degree into 60′, other parts, called minutes; each of these minutes being divided into 60″ seconds, each second into thirds, and so on.

DEHORS, in the military art, are all sorts of out-works in general, placed at some distance from the walls of a fortification, the better to secure the main places, and to protect the siege, &c. See FORTIFICATION.

DELINEATION, an outline or sketch. See DESIGN.

DELIVER. See SURRENDER.

DEMI-BASTION, or _half-bastion_, is a work with only one face and one flank. See FORTIFICATION.

DEMI-CANNON. See CANNON.

DEMI-CULVERIN. See CANNON.

DEMI-DISTANCE _des polygones_, _Fr._ is the distance between the exterior polygons and the angles.

DEMI-DISTANCES, _Fr._ half distances: as _serrez la colonne à demi-distances_, close to the column at half distances.

DEMI-FILE, _Fr._ is that rank in a French battalion, which immediately succeeds to the _serre-demi-file_, and is at the head of the remaining half of its depth.

DEMI-LANCE, a light lance or spear.

DEMI-LINE, in fortification, is a work placed before the curtain to cover it and prevent the flanks from being discovered sideways. It is made of two faces, meeting in an outward angle. See FORTIFICATION.

DEMI-GORGE, in fortification, is half the gorge, or entrance into the bastion, not taken directly from angle to angle, where the bastion joins the curtain, but from the angle of the flank to the centre of the bastion; or the angle which the two curtains would make, by their prolongation. See FORTIFICATION.

DEMISSION, _Fr._ Resignation.

DEMOLITION, the act of overthrowing buildings.

DENIZEN, a free man, residing in a country or state, and owing allegiance, as opposed to Alien, which means a person not a citizen, and who owes or acknowleges a foreign allegiance.

DENONCIATEUR _d’un déserteur_, _Fr._ During the old government of France, a military regulation existed by which any person who discovered a deserter, was entitled to his full discharge, if a soldier: and to one hundred livres, or eleven dollars reward.

DENONCIATEUR, in a general sense, may not improperly be called a military informer. So rigid indeed, were the regulations (even in the most corrupt state of the French government) against every species of misapplication and embezzlement, that if a private dragoon gave information to the commissary of musters of a troop horse that had passed muster, having been used in the private service of an officer, he was entitled not only to his discharge, but received moreover one hundred livres in cash, and became master of the horse and equipage, with which he retired unmolested. It is not mentioned in the publication from which we extract this remark, whether the officer was cashiered, &c. but we presume he was.

One hundred and fifty livres were likewise paid to any dragoon, or soldier who should give information of a premeditated duel; he obtained moreover his discharge.

DENSITY _of bodies_. See MOTION.

DEPASSER (or DEBORDER), _Fr._ To over-run. In oblique movements, particular care should be taken not to afford an enemy that advances on the same points with yourself, the means of outflanking you; which must inevitably happen, should any part of your troops over-run their proper ground. For the instant such an error occurs, your antagonist will only have to form a retired flank, oppose you in front on that part, and charge the remainder in flank, after having cut off all the troops that had over-run.

_Se laisser_ DEPASSER, to suffer yourself to be overtaken.

DEPENSES, _Fr._ In a military sense, implies secret service money.

DEPLOY, to display, to spread out; a column is said to deploy, when the divisions open out, or extend to form line on some one of those divisions.

DEPLOYMENT, or _flank march_, in a military sense, the act of unfolding or expanding any given body of men, so as to extend their front. A _deployment_ may be made in various ways. The principal one is, from the close column into line. A battalion in close column may form in line on its front, on its rear, or on any central division, by the _deployment_, or flank march, and by which it successively uncovers and extends its several divisions.

In the passage of an obstacle, parts of the battalion are required to form in close column, and again _deploy_ into line; although the division formed upon, continues to be moveable. This, however, depends wholly upon the nature of the ground or country, over which the battalion is marching.

DEPLOYMENT _into line on a front division, the right in front_, is effected by halting that division in the alignement, and all the others in their true situations, parallel and well closed up to it; and then by taking a point for forming upon, and dressing by it in the prolongation of that division. For a minute explanation of the deployments on a rear and central division. See _American Military Library_.

_Oblique Deployments_ differ from those movements, which are made when a battalion stands perpendicular to the line on which it is to form. These _deployments_ are frequently made on an oblique line advanced, on an oblique line retired: and when the close column halted is to form in line in the prolongation of its flank, and on either the front, rear, or central division. See _Am. Mil. Lib._

DEPOT, any particular place in which military stores are deposited for the use of the army. In a more extensive sense, it means several magazines collected together for that purpose. It also signifies an appropriated fort, or place, for the reception of recruits, or detached parties, belonging to different regiments. During hostilities, the greatest attention should be given to preserve the several _depots_ which belong to the fighting army. Hence the line of operation should be invariably connected with them; or rather no advance should be made upon that line, without the strictest regard being paid to the one of communication.

DEPOT is also used to denote a particular place at the tail of the trenches, out of the reach of the cannon of the place, where the troops generally assemble, who are ordered to attack the out-works, or support the troops in the trenches, when there is reason to imagine the besieged intend making a vigorous sally.

DEPOT, likewise means a temporary magazine for forage, for fascines, gabions, tools, and every other thing necessary for the support of an army, or for carrying on a siege.

DEPOUILLE, _Fr._ _mettre en dépouille_, is an expression made use of in casting of cannon, and signifies to strip it of the matting, clay, &c.

DEPOUILLES _de l’ennemi_, _Fr._ See SPOILS.

DEPRESSION, the placing of any piece of ordnance, so that its shot be thrown under the point blank line.

DEPRESSED _gun_, any piece of ordnance having its mouth depressed below the horizontal line.

DEPTH _of a battalion or squadron_, in military affairs, the number of ranks, or the quantity of men. Infantry were formerly drawn up 6 or 8 deep, that is, it consisted of so many ranks; but now the line of infantry are generally drawn up only 3 deep, and in defence of a breastwork but two deep. When infantry is drawn up 3 deep, the first rank is called the front rank; the second, the centre rank; and the third, the rear rank; and the files which bind the right and left, are called the flanks. The cavalry is drawn up 2 deep.

DEPTH, a technical word peculiarly applicable to bodies of men drawn up in line or column.

DEPTH _of formation_. The fundamental order of the infantry in which they should always form and act, and for which all their various operations and movements are calculated, is _three ranks_. The formation in _two ranks_ is regarded as an occasional exception that may be made from it, where an extended and covered front is to be occupied, or where an irregular enemy, who deals only in fire, is to be opposed. The formation in two ranks, and at open files, is calculated only for light troops in the attack and pursuit of a timid enemy, but not for making an impression on an opposite regular line, which vigorously assails, or resists.

DEPTH is not only applicable to men drawn up in line, and standing at close, or open files two or three _deep_, but it may likewise signify the relative depth of an army marching towards any given object, in desultory columns.

DEPUTY, a term given to persons employed in the civil departments of the army, and subject to superior trusts.

DEPUTY _pay-masters_.

DEPUTY _muster-masters_.

DEPUTY _commissaries_.

DEPUTY _judge-advocate_.

DEROUTE, _Fr._ The total overthrow of an army, battalion, or of any armed party. See DEFEAT.

_To_ DESCEND, signifies to leave any position on an eminence for immediate action.

_To_ DESCEND _upon_, to invade. When an enemy from surrounding heights suddenly marches against a fortified place, he is said to descend upon it. The term is also applied to troops debarking from their ships for the purpose of invasion.

DESCENT. Hostile invasion of any state or kingdom.

DESCENTES, _dans le fossé_, _Fr._ See DESCENTS _into the ditch_.

DESCENTS _into the ditch_, are cuts and excavations which are made by means of saps in the counterscarp beneath the covert way. They are covered with thick boards and hurdles, and a certain quantity of earth is thrown upon the top, in order to obviate the bad effects which might arise from shells, &c.

When the ditch or fossé is full of water, the _descent_ must be made to its edge, after which the ditch must be filled with strong fascines covered with earth. When the ditch is dry, the saps are carried on to the bottom, and traverses are made in order to secure a lodgment, or to render the approaches of the miner more practicable. When the ditch or fossé which is full of water, has little or no bank, the _descent_ is simply made over it, care being taken to cover its enfilade or range with blinds and chandeliers, or to execute it as much out of that line as possible.

DESCENTS, in fortification, are the holes, vaults, and hollow places, made by undermining the ground.

DESCRIPTION, _Signalement_, _Fr._ The description of a man’s person, his appearance, &c. It not only signifies the figure, but an exact and specific detail of such marks and prominent features, that by comparing the copy taken on paper with the original, the latter may be instantly recognised. It is the custom in all well regulated armies for every regiment to have an exact description of each man that belongs to it, specifically drawn out in the adjutant’s books. So that when a soldier deserts, a copy is instantly taken, and forwarded to those places to which he is most likely to resort.

DESERTER, in a military sense, a soldier who, by running away from his regiment, troop, or company, abandons the service.

DESERTERS. A prudent officer will always be cautious of what he entrusts to a deserter; the judgment of the officer and his knowlege of human character, are the only guides which he has in his conduct; the motives of the deserter are therefore to be considered, whether it was the result of depravity in himself or of causes which might affect a generous mind. In this case, however, he should be as cautious as if it proved to be depravity only. A deserter on reaching the lines is put under arrest and conducted to the commanding officer, where he is examined, and it is usual to notify him he will be punished with death as a spy if he gives false information. Though great caution is required in regard to the information given by deserters, great advantage may be derived from their information, as attacks premeditated, the positions of officers, corps, and magazines, and head quarters, of discontents in the army, or disagreements among the superior officers.

DESERTERS from the militia may be apprehended by any person in the same manner, that deserters are from the regular army. Persons apprehending a deserter are entitled to 10 dollars.

_Penalty of_ DESERTION. All officers and soldiers, who having received pay, or having been duly enlisted in the U. S. service, shall be convicted of having deserted the same, shall suffer death or such other punishment as by a court-martial shall be inflicted. _Art. War_, § 20, 21, 22, 23.