Denonciateur (Fr.). 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 not only entitled to his discharge, but received, moreover, 100 livres in cash, and became master of the horse and equipage, with which he retired unmolested. The officer was summarily dealt with.
Densimeter. An apparatus for obtaining the specific gravity of gunpowder by immersing it in mercury. It consists of an open vessel containing mercury, a frame supporting a glass globe communicating by a tube with the mercury in the open vessel, and joined at top to a graduated glass tube, which communicates by a flexible tube with an ordinary air-pump. Stop-cocks are inserted in the tubes above and below the glass globe, and a diaphragm of chamois-skin is placed over the bottom orifice and one of wire cloth over the top orifice of the globe. The arrangement allows the globe to be filled with mercury to any mark on the graduated tube, or with gunpowder and mercury. The globe can be taken off and weighed in both cases. The specific gravity is obtained from the relation between the weights in the two cases.
Density. The density or specific gravity of gunpowder is one of its most important properties. In the form of dust, the velocity of combustion increases rapidly with the density up to about 1.60, when it decreases. In grained powder the velocity of combustion decreases as the density increases. For English or American powder this velocity is about four-tenths of an inch per second. For French and most of the continental powders, which are less dense than the English, it is about forty-eight-hundredths of an inch. The excellent preservative qualities of English and American powders are largely due to their high densities—the standard being about 1.75. A certain degree of density is absolutely essential to grain powder to prevent the inflamed gases from penetrating the pores of the powder and flashing off the whole mass to the destruction of the gun. In the manufacture of powder the density depends, first, upon the amount of trituration to which the ingredients are subjected in the incorporating mill; second, upon the pressure employed to form the cake; and, third, upon the degree of moisture it contains when subjected to these operations, particularly the last. The pressure-gauge is not a reliable measure of the density given to a powder, though a good indication of the hardness, with which density must not be confounded. Dry powder meal offers a great resistance to compression, but becomes very hard—the work being consumed in consolidating the surface particles. To obtain uniform density a certain amount of moisture is necessary to assist the particles in their movement. As much as 6 per cent. of moisture is used in making prismatic powder.
Department Commander. See Geographical Department, Commander of.
Department, Military. A military subdivision of a country. The whole territory of the United States is divided into military departments, each under a general officer. See Geographical Department, Commander of.
Department of War. That department of a government which takes charge of all matters relating to war. See Secretary of War.
Depenses (Fr.). In a military sense, implies secret service money.
Deploy. Signifies a military movement, in which a body of troops is spread out in such a way that they shall display a wider front and a smaller depth than before deploying. To ploy is to execute the reverse of this movement.
Deployment. The act of unfolding or expanding any given body of men, in order to extend their front.
Deposits, Soldiers’. Soldiers in the U. S. service may deposit with the paymaster any portion of their savings, in sums not less than $5, the same to remain so deposited until final payment on discharge. Interest on deposits at the rate of 4 per cent. per annum will be paid on final settlement upon each deposit from the date thereof to date of discharge. No interest is payable, however, upon any deposit of less than $50, or upon any sum, whatever its amount, which has been on deposit for a less period than six months prior to date of discharge. Deposits are forfeited by desertion.
Depot. Any place at which military stores are deposited for the use of an army. It also signifies a fort or other suitable place appropriated for the reception of recruits, or detached parties belonging to different regiments. In fortification, the term is likewise used to denote a particular place at the trail of the trenches out of the reach of the cannon of a besieged place. It is here that besiegers generally assemble when ordered to attack the outworks, or support the troops in the trenches when there is reason to imagine the besieged intend making a sally.
Depredate. To take plunder or prey; to commit waste; as, the troops depredated on the country; also, in an active sense, to plunder or pillage; to spoil; to lay waste.
Depressed Gun. Any piece of ordnance having its mouth depressed below the horizontal line.
Depression. The pointing of any piece of ordnance so that its shot may be projected short of the point-blank.
Depth. A technical word, peculiarly applicable to bodies of men drawn up in line or column. The depth of a battalion or squadron is the number of men in rank and file from front to rear.
Deputy-Marshal. In the British service, is the senior sergeant-major of each regiment of Foot Guards, who sees after and makes out the routes of deserters, and receives an allowance for so doing.
Deraser (Fr.). To cut off the superfluous clay from a gun-mold previous to its being placed in the pit.
Derayeh, El. A town of Arabia, nearly in the centre of the district called El Nedjed. It is tolerably well fortified, but after a siege of seven months, in 1819, it was nearly destroyed by the troops of Ibrahim Pasha.
Derbend, or Derbent. A town of Russia, the capital of the province of Daghestan. It is surrounded by strong walls and flanked and strengthened by massive bastions. It was taken from Persia by Russia in 1722, restored to the former power in 1735, and retaken by the Muscovites in 1795.
Derivation (Fr.). Drift of rifle projectiles. See Projectiles.
Descend. In a military sense, means to make an attack or incursion as if from a vantage-ground.
Descents. In fortification, are the holes, vaults, and hollow places made by undermining the ground.
Descents into the Ditch. Cuts and excavations 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, etc.
Descriptive Book. A book in which descriptive lists of the soldiers belonging to a company are kept.
Descriptive List of Soldier. A paper giving a short history of the soldier, a description of his person, and the statement of his account. It accompanies him wherever he goes, being intrusted to his detachment or company commander.
Descriptive Memoir. This memoir, which should always accompany a sketch of a topographical reconnoissance, is intended to convey that information relating to the natural features of the ground not expressed upon the sketch; to express that information for which there are no conventional signs, and to present those facts relative to the ground which become important by being considered