Part 3

_Left_ ABOUT, is when the soldier changes the situation of his person by a semi-circular movement to the left.

ABREAST, a term formerly used to express any number of men in front. At present they are determined by Files.

ABRI, _Fr._ shelter, cover. _Etre à l’abri_, to be under cover, as of a wood, hillock, &c.

ABSCISSA, _in military mathematics_, signifies any part of the diameter or axis of a curve, contained between its vertex or some other fixed point, and the intersection of the ordinate.

In the parabola, the _abscissa_ is a third proportional to the parameter and the ordinate.

In the ellipsis, the square of the ordinate is equal to the rectangle under the parameter and _abscissa_, lessened by another rectangle under the said _abscissa_, and a fourth proportional to the axis, the parameter, and the _abscissa_.

In the hyperbola, the squares of the ordinates are as the rectangles of the _abscissa_ by another line, compounded of the _abscissa_ and the transverse axis.

But it must be remembered, that the two proportions relating to the ellipsis and hyperbola, the origin of the _abscissas_, or point from whence they began to be reckoned, is supposed to be the vertex of the curve, or, which amounts to the same thing, the point where the axis meets it; for if the origin of the _abscissa_ be taken from the centre, as is often done, the above proportions will not be true.

ABSENT, a term used in military returns. It forms a part of regimental reports, to account for the deficiency of any given number of officers or soldiers; and is usually distinguished under two principal heads, viz.

ABSENT _with leave_, officers with permission, or non-commissioned officers and soldiers on furlough.

ABSENT _without leave_. Men who desert are frequently reported _absent without leave_, for the specific purpose of bringing their crime under regimental cognizance, and to prevent them from being tried capitally, for desertion.

ABSOLUTE _Gravity_, in philosophy, is the whole force by which a body, shell, or shot, is impelled towards the centre. See GRAVITY.

ABSOLUTE _Number_, in Algebra, is the known quantity which possesses entirely one side of the equation. Thus, in the equation, _xx_ + 10_x_, = 64, the number 64, possessing entirely one side of the equation, is called the _absolute number_, and is equal to the square of the unknown root _x_, added to 10_x_, or to 10 times _x_.

ABUTMENT. See BRIDGES.

ACADEMY, in antiquity, the name of a villa situated about a mile from the city of Athens, where Plato and his followers assembled for conversing on philosophical subjects; and hence they acquired the name of _Academics_.

The term _Academy_ is frequently used among the moderns for a society, of learned persons, instituted for the cultivation and improvement of arts or sciences. Some authors confound _academy_ with university; but, though much the same in Latin, they are very different things in English. An university is, properly, a body composed of graduates in the several faculties; of professors, who teach in the public schools; of regents or tutors, and students who learn under them, and aspire likewise to degrees; whereas an _academy_ was originally not intended for teaching, or to profess any art, but to improve it; it was not for novices to be instructed in, but for those who were more knowing; for persons of distinguished abilities to confer in, and communicate their lights and discoveries to each other, for their mutual benefit and improvement. The first _academy_ we read of, was established by Charlemagne, by the advice of Alcuin: it was composed of the chief wits of the court, the emperor himself being a member.

_Military_ ACADEMY. There are in England two royal military academies, one at Woolwich, and one at Portsmouth. The first was established by king George II. in 1741, endowed, and supported, for the instructing of the people belonging to the military branch of ordnance, in the several parts of mathematics necessary to qualify them for the service of the artillery, and the business of engineers. The lectures of the masters in theory were then duly attended by the practitioner-engineers, officers, serjeants, corporals, private men, and cadets. At present the gentlemen educated at this academy are the sons of the nobility and military officers. They are called gentlemen cadets, and are not admitted under 14 and not above 16 years of age. They are taught writing, arithmetic, algebra, Latin, French, mathematics, mechanics, surveying, levelling, and fortification, together with the attack and defence; gunnery, mining, laboratory works, geography, perspective, fencing, dancing, &c. The master-general of the ordnance is always captain of the company of gentlemen cadets, and some officer of merit is always captain-lieutenant. There is, besides, a first lieutenant, and two second lieutenants. They are further under the immediate care of a lieutenant-governor, and an inspector, who are officers of great abilities and experience; and the professors and masters are men of known talents and capacity. That at Portsmouth was founded by George I. in 1722, for teaching of the branches of the mathematics which more immediately relate to navigation.

For the American and French _Military Academies_, see SCHOOL.

ACANZI, in military history, the name of the Turkish light-horse that form the van-guard of the Grand Signior’s army on a march.

ACCELERATED _Motion on oblique or inclined-planes_. See MOTION.

ACCELERATED _Motion of pendulums_. See PENDULUMS.

ACCELERATED _Motion of Projectiles_. See PROJECTILES.

ACCENDONES, in military antiquity, a kind of gladiators, or supernumeraries, whose office was to excite and animate the combatants during the engagement.

ACCENSI, in antiquity, were officers attending the Roman magistrates; their business was to summon the people to the public games, and to assist the prætor when he sat on the bench.

_Accensi_, in military antiquity, was also an appellation given to a kind of adjutants appointed by the tribune to assist each centurion and decurion. According to Festus, they were supernumerary soldiers, whose duty it was to attend their leaders, and supply the places of those who were either killed or wounded. Livy mentions them as irregular troops, but little esteemed. Salmasius says, they were taken out of the fifth class of the poor citizens of Rome.

ACCESSIBLE, that which may be approached. We say, in a military stile, that place, or that fortress, is _accessible_ from the sea, or land, i. e. it may be entered on those sides.

An accessible height or distance, in geometry, is that which may be measured by applying a rule, &c. to it: or rather, it is a height, the foot whereof may be approached, and from whence any distance may be measured on the ground.

Heights, both accessible, and inaccessible, may be taken with a quadrant. See ALTITUDE; and the article on Field Fortifications in the _American Military Library_, Theorem 11, 12, 13, 14, 15.

One of the objects of surveying, is the measuring both accessible and inaccessible distances.

ACCLIVITY, in a military sense, is the steepness or slope of any work, inclined to the horizon, reckoned upwards. Some writers on fortification use acclivity as synonymous with _talus_; though _talus_ is commonly used to denote all manner of slopes, either in its ascendent or descendent state.

ACCONTIUM, in ancient military writers, a kind of Grecian dart or javelin, somewhat resembling the Roman _pilum_.

ACCOUTREMENTS, in a military sense, signify habits, equipage, or furniture, of a soldier, such as belts, pouches, cartridge-boxes, saddles, bridles, &c. Accoutrements should be made of stout leather, not of the spongy kind, which is always stretching, and difficult to clean. The belts are about 2¹⁄₄ inches broad, with two buckles to fix them to the pouch. Pouches are made of the stoutest blackened leather, especially the outside flaps, which are of such a substance as to turn the severest rain. Cartridge-boxes are made as light as possible, with holes in each, to hold cartridges. See CARTRIDGE.

ACLIDES, in Roman antiquity, a kind of missive weapon, with a thong fixed to it, whereby it might be drawn back again. Most authors describe the _aclides_ as a sort of dart or javelin: but Scaliger makes it roundish or globular, with a wooden stem to poise it by.

ACOLUTHI, in military antiquity, was a title in the Grecian empire, given to the captain or commander of the _varangi_, or body-guards, appointed for the security of the emperor’s palace.

ACTIAN _games_ in antiquity, were games instituted, or at least restored, by Augustus, in memory of the famous victory, at Actium, over Mark Antony.

ACTIAN _years_, in chronology, a series of years, commencing with the epocha of the battle of Actium, otherwise called the æra of Augustus.

ACTION, in the military art, is an engagement between two armies, or any smaller body of troops, or between different bodies belonging thereto. The word is likewise used to signify some memorable act done by an officer, soldier, detachment or party.

ACTIVITY, in a military sense, denotes laboriousness, attention, labor, diligence and study.

ACUTE _angle_. See ANGLE.

ADACTED applies to stakes, or piles, driven into the earth by large malls shod with iron, as in securing ramparts or pontoons.

ADDICE, a sort of axe which cuts horizontally. It is sometimes called an Adze.

ADIT, a passage under ground, by which miners approach the part they intend to sap. See GALLERY.

ADJUTANT-GENERAL is a staff officer, who aids and assists a general in his laborious duties: he forms the several details of duty of the army, with the brigade-majors, and keeps an exact state of each brigade and regiment, with a roll of the lieutenant-generals, major-generals, colonels, lieutenant-colonels, and majors. He every day at head quarters receives orders from the general officer of the day, and distributes them to the majors of brigades, from whom he receives the number of men they are to furnish for the duty of the army, and informs them of any detail which may concern them. On marching days he accompanies the general to the ground of the camp. He makes a daily report of the situation of all the posts placed for the safety of the army, and of any changes made in their posts. In a day of battle he acts as aid to the general. In a siege he visits the several posts and guards of the trenches, and reports their situation, and how circumstanced: he gives and signs all orders for skirmishing parties (if time permit) and has a serjeant from each brigade to carry any orders which he may have to send. See _American Mil. Lib._ Article STAFF.

ADJUTANT, an officer who aids the major in part of his duty, and performs it in his absence. He receives orders from the brigade-major, if in camp; and when in garrison, from the town-major: after he has carried them to his colonel or officer commanding the regiment, he then assembles the serjeant-major, drum-major and fife-major, with a serjeant and corporal of each company, who write the orders in an orderly book, to shew to their respective officers. If convoys, parties, detachments, or guards, are to be furnished, he gives the number which each company is to furnish, and hour and place for the assembling: he must keep an exact roster and roll of duties, and have a perfect knowlege of all manœuvres, &c. This post is usually given to an active subaltern.

ADMIRAL, on the European establishiments, when on shore, are entitled to receive military honors, and rank with generals in the army.

ADVANCE. See PAY in Advance.

ADVANCED signifies some part of an army in front of the rest, as in _advanced guards_, which always precede the line of march or operations of a body of troops; again, as when a battalion, or guns of a second line are brought up in front and before the first line. This term also applies to the promotions of officers and soldiers.

{_Fossé_} See FORTIFICATION. ADVANCED {_Ditch_} {_Guard._ See GUARD.

ADVANCEMENT, in a military sense, signifies honor, promotion, or preferment, in the army, regiment or company.

ADVANTAGE _Ground_, a ground that gives superiority, or an opportunity of annoyance or resistance.

ADVICE-_Boat_, a vessel employed for intelligence.

ADVOCATE _General_. See JUDGE _Martial_.

ÆNEATORES, in military antiquity, the musicians in an army; including those who sounded the trumpets, horns, _litui_, _buccincæ_, &c.

AFFAIR, in the military acceptation of the word, means any slight action or engagement.

AFFAIR _of Honor_, a duel.

AFFAMER, _une Place_, _Fr._ to besiege a place so closely as to starve the garrison and inhabitants. See BLOCKADE.

AFFIDAVIT, in military law, signifies an oath taken before some person who is properly authorised to administer it; as first, when a soldier is inlisted, when it is stiled an attestation; secondly, by all officers appointed on a court-martial; thirdly, by the commissaries, or muster-masters.

AFFRONTER, _Fr._ to encounter or attack boldly.

AFFUT, the French name for a gun-carriage, and for which we have no appropriate name; the only distinction from all other carriages is, that it belongs to a gun. See CARRIAGE.

AGA, in the Turkish army, is the same as a general with us.

AGE. A young man must be 14 years old before he can become an officer in the English army, or be entered as a cadet at Woolwich, in the English academy.

Persons are enlisted for soldiers from 17 to 45. After the latter age, every inhabitant is exempted from serving in the British militia.

By a late regulation in England, growing boys may be enlisted under 16 years of age. These recruits are chiefly intended for the East-India service.

In the United States 18 to 45 is the legal age for militia and regulars.

The Romans were obliged to enter themselves in the army at the age of 17 years; at 45 they might demand their dismission. Amongst the Lombards, the age of entry was between 18 and 19; among the Saxons, at 13.

AGEMA, in the ancient military art, a kind of soldiery chiefly in the Macedonian armies. The word is Greek, and literally denotes vehemence, to express the strength and eagerness of this corps. Some authors will have _agema_ to denote a certain number of picked men, answering to a legion among the Romans.

AGENCY, a certain proportion of money which is ordered to be subtracted from the pay and allowances of the British army, for transacting the business of the several regiments composing it.

AGENT, a person in the civil department of the British army, between the paymaster-general and the paymaster of the regiment, through whom every regimental concern of a pecuniary nature must be transacted. He gives security to government for all monies which pass through his hands in the capacity of an Agent--and by the Mutiny Act, it was provided, That if an Agent shall withhold the Pay of Officers or Soldiers for the Space of one Month, he should be dismissed from his Office and forfeit 100_l._

The army agency has since been incorporated with the British war office, and forms a special department.

_Military_ AGENT in the United States is a civil officer whose duty is the transporting of clothing and other articles; and the expenditures for other services attached to the military department; they act under direct orders from the War Department.

AGGER, in ancient military writers, denotes the middle part of a military road, raised into a ridge, with a gentle slope on each side, to make a drain for the water, and keep the way dry.

AGGER is also used for the whole road, or military way. Where highways were to be made in low grounds, as between two hills, the Romans used to raise them above the adjacent land, so as to make them of a level with the hills. These banks they called _aggeres_. Bergier mentions several in the _Gallia Belgica_, which were thus raised 10, 15, or 20 feet above ground, and 5 or 6 leagues long. They are sometimes called _aggeres calceati_, or causeways.

AGGER, also, denotes a work of fortification, used both for the defence and the attack of towns, camps, &c. in which sense _agger_ is the same with what was otherwise called _vallum_, and in later times, _agestum_: and among the moderns, _lines_; sometimes, _cavaliers_, _terrasses_, &c.

The _agger_ was usually a bank, or elevation of earth, or other matter, bound and supported with timber; having sometimes turrets on the top, wherein the workmen, engineers, and soldiery, were placed. It had also a ditch, which served as its chief defence. The height of the _agger_ was frequently equal to that of the wall of the place. Cæsar tells us of one he made, which was 30 feet high, and 330 feet broad. Besides the use of _aggers_ before towns, they generally used to fortify their camps with them; for want of which precaution, divers armies have been surprised and ruined.

There were vast _aggers_ made in towns and places on the sea-side, fortified with towers, castles, &c. Those made by Cæsar and Pompey, at Brundusium, are famous. Sometimes _aggers_ were even built across arms of the sea, lakes, and morasses; as was done by Alexander before Tyre, and by M. Antony and Cassius.

The wall of Severus, in the north of England, may be considered as a grand _agger_, to which belong several lesser ones. Besides, the principal _agger_ or _vallum_, on the brink of the ditch, Mr. Horsley describes another on the south side of the former, about 5 paces distant from it, which he calls the south _agger_; and another larger one, on the north side of the ditch, called the north _agger_. This latter he conjectures to have served as a military way; the former, probably, was made for the inner defence, in case the enemy should beat them from any part of the principal _vallum_, or to protect the soldiers against any sudden attack from the provincial Britons.

AGGER _Tarquinii_, was a famous fence built by Tarquinius Superbus, on the east side of Rome, to stop the incursions of the Latins, and other enemies, whereby the city might be invested.

AGGER is also used for the earth dug out of a ditch or trench, and thrown up on the brink of it: in which sense, the Chevalier Folard thinks the word to be understood, when used in the plural number, since we can hardly suppose they would raise a number of cavaliers, or terrasses.

AGGER is also used for a bank or wall, erected against the sea, or some great river, to confine or keep it within bounds; in which sense, _agger_ amounts to the same with what the ancients called _tumulus_ and _moles_; the Dutch, _dyke_; and we, _dam_, _sea-wall_; the Asiatics call them _bunds_, &c.

AGIADES, in the Turkish armies, are a kind of pioneers, or rather field engineers, employed in fortifying the camp, &c.

AGUERRI, _Fr._ an officer or soldier experienced in war; a veteran.

AIDE-DE-CAMP, an officer appointed to attend a general officer, in the field, in winter-quarters, and in garrison; he receives and carries the orders, as occasion requires. He is taken from the line, and all aids-de-camp have extra pay allowed for their duty. This employment is of greater importance than has been generally believed: it has been, however, too often entrusted to young officers of little experience, and of as little capacity; but in the French service they bestow great attention on this article. Marshal de Puysegur mentions the loss of a battle through the incapacity of an aide-de-camp. On the English establishment, generals, being field marshals, have _four_, lieutenant-generals _two_, and major-generals and brigadier-generals _one_.

In the United States the number is established by law; though on service the number must necessarily be equal to the exigency, or the various points to which orders must be sent. See _American Mil. Lib._ Article STAFF.

AIDE _du Parc des Vivres_, _Fr._ an officer in France, acting immediately under the commissary of stores and provisions.

AID-MAJOR. See ADJUTANT.

AIGREMORE, a term used by the artificers in the laboratory, to express the charcoal in a state fitted for the making of powder.

AIGUILLE, an instrument used by engineers to pierce a rock for the lodgement of powder, as in a mine; or to mine a rock, so as to excavate and make roads.

AILE, _Fr._ a wing or flank of an army or fortification.

AIM, the act of bringing the musquet, piece of ordnance, or any other missive weapon, to its proper line of direction with the object intended to be struck.

AIM FRONTLET, a piece of wood hollowed out to fit the muzzle of a gun, to make it of an equal height with the breech, formerly made use of by the gunners, to level and direct their pieces. It is not used at present.

AIR-GUN, a pneumatic machine for exploding bullets, &c. with great violence.

The common air-gun is made of brass, and has two barrels: the inside barrel is of a small bore, from whence the bullets are exploded; and a large barrel on the outside of it. There is likewise a syringe fixed in the stock of the gun by which the air is injected into the cavity between the two barrels through a valve. The ball is put down into its place in the small barrel with the rammer, as in any other gun. Another valve, being opened by the trigger, permits the air to come behind the bullet, so as to drive it out with great force. If this valve be opened and shut suddenly, one charge of condensed air may be sufficient for several discharges of bullets; but if the whole air be discharged on one single bullet, it will drive it out with uncommon force. This discharge is effected by means of a lock placed here, as usual in other guns; for the trigger being pulled, the cock will go down and drive the lever, which will open the valve, and let in the air upon the bullet: but as the expansive power of the condensed air diminishes at each discharge, its force is not determined with sufficient precision for the purposes of war. Hence it has been long out of use among military men.

In the air-gun, and all other cases where the air is required to be condensed to a very great degree, it will be necessary to have the syringe of a small bore, viz. not exceeding half an inch in diameter; because the pressure against every square inch is about 15 pounds, and therefore against every circular inch about 12 pounds. If therefore the syringe be one inch in diameter, when the atmosphere is injected, there will be a resistance of 12 pounds against the piston; and when 10 are injected, there will be a force of 120 pounds to be overcome; whereas 10 atmospheres act against the circular half-inch piston (whose area is only ¹⁄₄ part so large) with only a force equal to 30 pounds; or 40 atmospheres may be injected with such a syringe, as well as 10 with the other. In short, the facility of working will be inversely as the squares of the diameter of the syringe.

AIR-SHAFTS, in mining. See MINING.

ALARM, is a sudden apprehension upon some report, which makes men run to their arms to stand upon their guard; it implies either the apprehension of being suddenly attacked, or the notice given of such an attack being actually made; generally signified by the firing of a cannon, or rocket, the beat of a drum, &c.

ALARM-_Post_, in the field, is the ground appointed by the quarter-master general for each regiment to march to, in case of an alarm.

ALARM-_Post_, in a garrison, is the place allotted by the governor for the troops to draw up in, on any sudden alarm.

_False_-ALARMS, are stratagems of war, frequently made use of to harrass an enemy, by keeping them perpetually under arms. They are often conveyed by false reports, occasioned by a fearful or negligent sentinel. A vigilant officer will sometimes make a false alarm, to try if his guards are strict upon duty.

ALARM _Bell_, the bell rung upon any sudden emergency, as a fire, mutiny, approach of an enemy, or the like, called by the French, Tocsin.