GLOSSARY of Military Terms Employed in the Text

(Consult also Alphabetical Index)

Abatis.—An obstacle consisting of felled trees, often interlaced with wire. The trees are felled or placed with their tops toward the enemy, the butts often remain attached to the stumps, or are secured to the ground by stakes.

Adjutant.—The executive officer of a command.

Advance cavalry.—See Cavalry.

Advance guard.—A body of troops which marches in front of a command in column of route to facilitate the march and protect the main body from surprise. See Chap. IV.

Advance party.—The leading formed element of an advance guard.

Advance supply depot.—A station for the issue of ammunition, rations and other supplies, where the trains attached to the combatant troops are sent to refill. See Chap. XVII.

Advanced position.—A defensive position in advance of the main line of defense.

Aiming point.—See Artillery fire.

Ambuscade.—A surprise attack delivered by a body lying in wait for its enemy.

Angle of site.—The inclination or slope of the ground as affecting the angles of elevation of artillery.

Applicatory method.—A system of military peace training by means of the solution of practical problems in strategy and tactics. These problems are solved on a map or on the terrain, and are called map problems, terrain exercises, war games, etc. See Chap. I.

Artillery.—The heavier pieces of ordnance, as distinguished from small arms and machine guns. Artillery includes guns, howitzers, and mortars of various calibers, and the troops attached thereto. All modern artillery is rifled. Mobile artillery is habitually mounted, both for transport and use, on wheeled carriages, and accompanies the mobile troops. See Ordnance.

Artillery fire.—See Chap. VIII. The usual method of fire of modern artillery is that which employs indirect laying. The guns are concealed and the target is usually not visible to the gunners. The officer directing the fire ascertains the range and direction of the target from one of the guns of the battery, called the directing gun. He also determines the difference in azimuth or direction (at the directing gun) between the target and some conspicuous object visible to all the gunners. This point is called the aiming point and the angular difference of azimuth of the target and the aiming point is known as the deflection. This is set off on the gun sight in such manner that when the sight is directed on the aiming point the gun will be directed on the target. Due to their different positions the deflections at the other guns will vary slightly from that at the directing gun. This variation is called the deflection difference. By varying the deflection and deflection difference the officer in charge may distribute the fire over the front of the target. The range is determined by the process known as bracketing. The approximate range having been estimated or determined by a mechanical range finder, a shot or group of shots is fired at the estimated range. They burst on impact, and from observation of the smoke it is possible to determine whether the shots are short of or over the target. The range is then increased or decreased and the firing continued until two consecutive bursts are obtained, one on either side of the target. Thus if a shot at 3,000 yds. bursts short of the target and one at 3,400 bursts over, it is known that the target lies between these ranges. Two shots at known ranges, one over and one short, form a bracket. The length of the bracket may be reduced by interpolating intermediate shots. Bracketing need not be done by a single piece. To save time a number of shots on both sides of the estimated range may be fired simultaneously by different pieces.

Barrage.—A zone or belt of the terrain more or less continuously swept by the fire of field artillery, with the purpose of preventing or discouraging the passage of hostile troops across the fire swept space. Such a barrage or curtain of fire might be designed to break down the fighting power of a line of battle by preventing the forwarding of ammunition, supplies and reinforcements. It may also be established in front of hostile line for the purpose of checking or breaking up an assault or counter-attack, etc.

Base depot.—See p. 365.

Billeting.—Quartering troops in the homes of local residents, who may be required also to furnish food. The practice is common in Europe but has seldom been employed in this country.

Bivouac.—A camp of very temporary nature, such as that of troops on the open field of battle. The shelter and bedding are such as the troops carry on their persons.

Bracket.—See Artillery fire.

Bomb-proof.—A shelter, usually subterranean, against high explosive shell.

Caisson.—A carriage for artillery ammunition. It consists of two parts, the body and limber, each mounted on wheels. The two parts may be separated. The limber is the forward portion to which the team is attached, and is identical with the limber to which the gun is attached on the march. The separation of the caisson body and limber, or of the gun and limber, is called unlimbering.

Cantonment.—A camp of rather permanent nature where the accommodations are more elaborate than in the ordinary camp under canvas. The shelters often consist of rough huts or simple frame buildings erected for the purpose. The term is also applied to portions of towns occupied by troops for a protracted stay.

Cavalry.—Cavalry, according to its uses, has several classifications:

Advance guard cavalry.—Attached to the advance guard.

Advance cavalry.—That portion of the advance guard cavalry which precedes the point of the advance guard.

Independent cavalry.—Cavalry operating independently of all save the supreme commander.

Outpost cavalry.—Attached to the outpost.

Rear cavalry.—Attached to the rear guard.

Chevaux-de-frise.—An obstacle in the form of a saw-horse with several legs.

Clinometer.—A small hand instrument used to measure the inclination or slope of the ground, or the angle of elevation of a gun.

Column.—A formation of troops in which the elements are placed one in rear of the other, as a column of route.

Combined sights.—See p. 331.

Communications.—The prepared routes by which troops move from one part of a position to another; also their lines of supply and reinforcement. The term is also applied to telegraph, telephone, and other signaling apparatus.

Connecting files.—See p. 61.

Conscription.—The act of impressing men for compulsory military service; the draft.

Contact squadron.—See p. 149.

Containing.—The act of restraining or delaying the movements of a hostile force, by attack or threatened attack, with the object of preventing its junction with other hostile forces. See p. 91.

Convoy.—See p. 95.

Cordon system of outposts.—See p. 184.

Cossack post.—A group on the line of observation of an outpost. It consists of four men, and places one sentinel.

Counter-attack.—Offensive operations by troops whose general attitude is or has been defensive. See p. 236.

Counter-mining.—The subterranean operations of troops on the defensive for the purpose of frustrating the efforts of the attack.

Cover.—Protection from fire or view, or both.

Crest, geographical or topographical.—The highest part of a ridge or elevation.

Crest, Military.—A line or position on the front slope of a hill or ridge which affords a good view of the whole or of some special portion of the foreground. Depending on the configuration of the terrain, it may or may not coincide with the geographical crest. See Fig. V, p. 135.

Curtain of fire.—See Barrage.

Danger space.—That portion of the trajectory in which the height of the projectile above the ground is less than the height of the target. The length of the danger space varies with the flatness of the trajectory and the height of the target. Thus, for a man standing, the danger space is that portion of the trajectory in which the height of the projectile above the ground does not exceed about 5 ft. 8 in.

Dead space.—A portion of the terrain, especially in front of a defensive position, not covered by fire; a defiladed area.

Defensive position.—A line or zone of the terrain occupied by troops and prepared for defense by means of field fortifications.

Defilade.—Vertical cover from view or from fire. Troops behind a crest are said to be defiladed if shots which skim the crest also pass over their heads. Flash defilade is a mask of sufficient height to conceal the flashes of guns.

Defile.—A narrow passage, such as a bridge or mountain pass, that prevents or embarrasses the deployment of troops passing through it.

Deflection.—See Artillery fire.

Delaying action.—A combat entered into for the purpose of temporarily delaying the enemy.

Demolition.—The destruction of material objects by any means.

Deployment.—An extension of the front, usually for the purpose of forming line of battle.

Deployment, depth of.—See p. 349.

Depth.—Space measured from front to rear.

Detonator.—A small charge of explosive used to ignite a larger charge.

Diagrammatic analysis.—See p. 29.

Direct laying.—See Artillery fire.

Directing gun.—See Artillery fire.

Distance.—See Depth.

Dispersion.—A separation of the elements of a command, especially when combat is imminent; the opposite of concentration.

Division.—A unit of army organization, the smallest which includes all branches of the service. In the United States Army a division has a strength of about 20,000. It includes infantry, cavalry, and field artillery, and the necessary special troops such as engineers, signal, sanitary, etc., with all the requisite wagon or motor transport.

Draft.—See Conscription.

Echelon.—A term applied to lines or groups that are stepped or “staggered” with respect to one another.

Elongation.—An increase in the usual road space or length of a column of troops, due to fatigue, poor discipline, or other causes.

Enfilade.—Fire from the flank, parallel or nearly parallel to the line against which it is directed. It is peculiarly effective and demoralizing to troops against which directed, and is therefore always carefully guarded against.

Envelopment.—An attack directed obliquely against the flank of a position. See Fig. IX, p. 219.

Estimate of the situation.—A mental review of a military situation made as a preliminary to and basis for a plan of action.

Examining post.—An outpost station at which persons endeavoring to pass through the lines are examined and identified.

Fascine.—A long cylindrical bundle of brush used as a flexible log in a revetment.

Feint.—An attack made primarily for the purpose of diverting the enemy’s attention from more important operations.

Field maneuver.—A practical problem in tactics prepared for solution on the terrain, with troops. Both combatants may be represented by real troops or one by imaginary troops.

File.—A single soldier; an element consisting of one front rank and one rear rank man. A column of files is one having a front of one or two men.

Fire superiority.—Superior moral or physical fire effect as compared to that of the adversary. Fire superiority is implied if the assailant can advance or force back the defender. Fire superiority for the defender is implied if he can hold his ground and check the advance of the assailant.

Firing data.—See p. 116.

Fixed ammunition.—Ammunition in which the projectile and propelling charge are a single piece, the charge being contained in a cylindrical metal case with the projectile fixed in the end like a rifle cartridge. It is used in all small arms and machine guns and in practically all of the smaller field guns and howitzers.

Flanks.—The extremities of a line of battle, outpost, etc., and the terrain in their vicinity.

Foraging.—The process of obtaining supplies, especially food, from the local inhabitants, force being used when necessary.

Forced march.—See p. 89.

Fortification.—Any engineering work or accessory device which increases the fighting power of troops by affording shelter or concealment or increased fire effect, or which restricts the tactical maneuvers or fire effect of the enemy.

Fortification, field or hasty.—Those works executed by combatant troops in the field to meet immediate tactical needs.

Fougasse.—A small land mine with a charge of explosive and broken stone. It is fired by powder fuse or electricity, as the enemy approaches.

Front.—The known or supposed direction of the enemy; the theater of active military operations as distinguished from the country in rear.

Frontage.—The extent of front of a command deployed for battle, of an outpost, etc.

Fuse.—A device used for detonating the explosive charge of a shell or shrapnel. Fuses are classified as time, percussion, combination (percussion and time), and delayed action. Time fuses detonate at the end of a given time, percussion fuses on impact. A delayed action fuse is one which delays the explosion of the charge until the projectile has penetrated the structure which it strikes. The term fuse is also applied to powder trains used to ignite placed charges of explosive in demolition. Electric fuses are devices which detonate a charge by means of the heating effect of an electric current. They are also called primers.

Gabion.—A hollow cylinder of brush or other material which is filled with earth and used as a revetment.

General Staff.—A corps of highly trained officers charged with the study of the conduct of war and the detailed methods of military operations. In time of war they direct and administer the operations of mobilization, concentration, supply, transportation, etc., and assist the field commanders in planning and executing their operations.

Grenade.—A charge of high explosive in a container hurled a relatively short distance by hand or by means of a catapult, rifle, or small mortar. The charge explodes by time fuse or concussion. Large grenades are called air mines or air torpedoes. They are distinguished from high explosive shell by their relatively short range, which ordinarily does not exceed 500 yards.

Guerrillas.—Irregular troops, not belonging to the organized combatant forces of a belligerent state, and not recognized by the laws of civilized warfare.

Gun.—A piece of ordnance fired from a platform or wheeled mount. A gun, as compared with a howitzer, has a relatively long barrel, flat trajectory and high velocity. Its effect is produced largely by the vigor of the blow struck by the projectile, which is usually combined with the action of a charge of explosive. Guns, according to their size and uses, are classed as mountain, light or heavy field, siege and seacoast. All modern guns are breech-loading rifles.

Head cover.—A vertical or nearly vertical shield of any material which protects the heads of troops from flat trajectory fire. See Overhead cover.

Heliograph.—An instrument used for signaling by flashing the rays of the sun from a mirror.

High explosive shell.—A projectile containing a charge of high explosive fired from a gun or howitzer. The charge explodes by time fuse or upon impact. It is used to demolish material objects, such as fortifications, but is often employed also against living targets.

Howitzer.—A piece of ordnance having, as compared with a gun, a short barrel, low velocity and curved trajectory. Its effect is produced chiefly by the explosion of the charge contained in the projectile. See Mortar.

Hurdle.—A revetment of woven brush.

Initial point.—A point of the terrain from which the starting times for all elements of a command are calculated for the commencement of a march. See p. 58.

Initiative.—A commander is said to have the initiative when he carries out a preconceived plan, dictating and controlling the course of operations and forcing the adversary to meet his lead. The initiative is ordinarily, though not always, possessed by the attacker, inasmuch as he usually selects the time, place and manner of attack, and forces the defender to adapt his measures to meet it. A vigorous counter attack, which forces a suspension of the attack, transfers the initiative to the original defender.

Interval.—An open space between adjacent men or adjacent organizations on the same line. It is measured parallel to the front.

Latrine.—A dry sewage pit or trench; a cesspool.

Leading troops.—The advanced elements of a command; more specifically a less formal substitute for an advance guard, employed in retreat or other situations where a regular advance guard is not required.

Limber.—A portion of an artillery carriage consisting of an ammunition chest mounted on two wheels, with a pole for the attachment of the team. For the march the field guns are attached to the limbers by engaging the eye at the end of the trail with a pin or pintle on the limber. See Caisson.

Line.—A general term applied to all combatant troops as distinguished from the non-combatant; a position occupied by troops, as a defensive or outpost line, etc.; a military formation in which the elements are placed alongside or abreast of each other. See Column and Echelon.

Line of columns.—A number of parallel columns of troops with their heads on the same line.

Line of communications.—See p. 363.

Line of investment.—A cordon of troops drawn around a fortress for the purpose of cutting off its supply and communication; usually the first step in siege operations for the reduction of the fortress.

Line of observation.—The line occupied by the sentinels and observing groups of an outpost. See Fig. VIII, p. 195.

Line of resistance.—Specifically, the prepared line of defense of an outpost, usually occupied by the supports. See Fig. VIII, p. 195.

Listening galleries.—Subterranean galleries driven to the front for the purpose of detecting the mining operations of the enemy.

Listening posts.—Sheltered positions in advance of a defensive line for the purpose of early detection of the enemy’s movements. They are connected with the main line by a communicating trench or subterranean gallery.

Loopholes.—Openings in a parapet or head cover through which fire is delivered.

Machine gun.—An automatic or semi-automatic gun of small caliber, capable of great rapidity of fire. It uses fixed ammunition, preferably identical with that employed in small arms. The ammunition is fed automatically from a hopper, clip or belt. Machine guns are of various sizes and types, but all are characterized by rather light construction and great mobility. Some require a crew of several men for their operation, others are operated by a single individual. There is hence no sharp line of demarcation between machine guns and automatic rifles. See p. 304.

Maneuver.—A movement of a body of troops. Strategical maneuvers include movements of troops, on a relatively large scale in preparation for prospective battle, but usually at a distance from the enemy. Tactical maneuvers include movements executed on the battlefield or in the near presence of the enemy. As compared with strategical maneuvers they are usually on a smaller scale, in closer proximity to the enemy, and more immediately related to battle tactics.

Map distance.—The horizontal interval between contours (on the map) corresponding to a given slope or gradient.

Map maneuver.—A tactical study or exercise followed out on a map.

Map measure.—A recording or counting device used for measuring distances on a map.

Map problem.—A real or imaginary tactical problem solved on a map. See Chap. I.

March outposts.—Temporary outposts placed by a marching column during a halt or at the end of a day’s march. They are withdrawn on resuming the march or when the regular outpost is in position.

Marginal distribution.—An outline of the dispositions of troops placed in the margin of a field order. See pp. 40 and 342.

Mask.—A cover from hostile view or fire.

Matériel.—The equipment and non-expendable supplies of an army; any material object.

Melée.—Specifically, the confusion following a cavalry charge, often characterized by hand to hand combat.

Mil.—A unit of angular measurement, the inverse tangent of one thousandth. See p. 109.

Mine.—A subterranean charge of explosive, used to destroy hostile fortifications.

Mining.—The operations of subterranean attack and defense.

Mission.—The aim or purpose of a commander on which his decisions and plans are based.

Mobility.—The power of rapid movement. Mobile troops are those capable of quickly changing their location and dispositions to meet tactical needs. Non-mobile troops are capable only of passive defense. It is therefore essential that first line troops shall be highly mobile. Otherwise they cannot seize or retain the initiative. Even in defensive operations mobility is essential to meet the movements of the assailant.

Mobilization.—The change from peace to war footing. An army is said to be mobilized when it is assembled, organized, armed, and equipped to take the field.

Morale.—The collective psychological condition or spirit of troops, especially combatant troops engaged in battle. High morale is implied when troops respond readily to the will of their commander. Morale is therefore measured by the extent to which troops submit to the control of their officers.

Mortar.—A piece of ordnance having a very short barrel, low velocity, and curved trajectory. It throws a projectile containing a large charge of high explosive, at angles of elevation varying from 45 degrees to 60 degrees so as to drop the projectile on top of its target.

Mutual support.—Two or more portions of a firing line which can cross fire on a part of the front of the position are said to afford mutual support.

Obstacle.—Any natural object or artificial device which retards the enemy’s movements without affording him shelter from fire. See p. 216.

Orders, field.—Written or verbal orders covering the tactical dispositions and operations of combatant troops. See Chap. II.

Ordnance.—A collective term applied to all firearms which hurl projectiles. As generally used the term excludes small arms, such as rifles and pistols, and applies especially to the heavier pieces. See Small arms and Artillery.

Outguard.—One of the observing groups of an outpost. See p. 183.

Organization.—For the organization of all tactical units in the U. S. Army, see p. 10 et seq.

Outpost.—A line of observation and resistance established between a body of troops and the known or supposed position of the enemy, to guard against surprise attacks.

Overhead cover.—A horizontal or inclined shield of any material which extends over the heads of the troops and protects them from grenades or high angle fire. See Head cover.

Pack train.—A train of animals, usually mules, carrying packs on saddles. This form of transportation is used in mountainous country or where roads are very poor.

Parados.—A bank of earth in rear of a trench to protect the occupants from the back draft of shells bursting behind the trench.

Parapet.—A bank of earth or other material in front of a trench or emplacement which protects the occupants from fire.

Patrol.—A small body of troops, foot or mounted, sent out from a larger body for the purposes of observation and reconnaissance. See Chap. III, pp. 165, 185, 212, etc.

Percussion.—See Fuse.

Picket.—A large outguard.

Pioneer.—A member of the mobile engineer forces of an army.

Platoon.—A division of a company, troop or battery.

Platoon column.—A platoon in double column of files. This formation is much used in advancing under fire, especially in rough country.

Point.—The extreme forward element of an advance guard, or rear element of a rear guard.

Ponton.—A portable boat used as a support or pier for a floating bridge.

Ponton equipage.—The portable floating bridge equipment of an army.

Position fire.—See p. 325.

Position in readiness.—See p. 308.

Pusher.—An aeroplane in which the propeller is placed in the back of the machine.

Railhead.—The forward limit of rail transport for the supplies and reinforcements of an army.

Range finder.—Any device for determining distances.

Ration.—The daily food allowance of a soldier.

Reconnaissance.—A rapid examination of a hostile body of troops, structure, locality, district, etc., for the purpose of noting features and gathering information of military value.

Re-entrant.—A more or less sharp projection from a line toward the rear. See Salient.

Reinforced brigade.—A brigade of infantry with attached auxiliary troops, usually on an independent mission.

Relay post.—See p. 53.

Rencontre.—See p. 295.

Requisition.—A demand for supplies made by an army upon the local inhabitants.

Reserves.—Troops temporarily withheld from action for the purpose of reinforcement at critical times and places, to meet emergencies, etc. As distinguished from supports, the place of their employment in combat cannot always be foreseen. Also, individuals who have undergone military training and are available for service but not at the time a part of the standing army.

Revetment.—Any device used to retain earth or other material at a slope steeper than the natural slope.

Road space.—The distance covered by an organization in its usual marching formation or column of route. See p. 16.

Salient.—A more or less sharp projection from a line toward the front.

Salvo.—See p. 114.

Sap.—A zigzag trench dug for the purpose of a covered advance against the enemy.

Screen.—A feature of the terrain which favors concealment. A disposition of troops designed to prevent the enemy from obtaining information. See p. 165.

Sentry squad.—A group on the line of observation of an outpost. It consists of eight men and places a double sentinel.

Shrapnel.—A projectile containing a number of small bullets or fragments with a propelling charge. It explodes in the air and scatters the bullets and fragments of the case over a considerable area, being in effect a flying shotgun. The shrapnel of the 3-inch, U. S. field gun, when properly burst, will sweep an area 200 to 300 yards in depth and 20 to 25 yards in width, killing or seriously wounding any man or animal in the area. It has little effect on fortifications and is used only against troops. Shrapnel is hence known as the “man-killing projectile.”

Siege.—The formal investment and attack of a fortress. A fortified place may be reduced by cutting off its supply, by assault, or by both methods. Occasionally the actual reduction of the fortress is not attempted, it being simply covered by a force of sufficient strength to prevent the garrison of the fortress from interfering with the operations of the invader.

Situation, general and special.—The (real or imaginary) circumstances or conditions confronting a body of troops at any stated time. A military situation has two parts which are described as general and special, or with respect to time and place, as distant and immediate. Past events and future possibilities or probabilities usually form part of the situation. See p. 20.

Small arms.—Firearms, such as rifles and pistols, carried by individuals. The term is occasionally applied also to machine guns which use small arms cartridges.

Spar bridge.—A type of military bridge in which the support consists of two trestles which are tilted toward each other and locked together.

Splinter-proof.—A shelter similar to a bomb-proof but designed to afford protection only against rifle bullets, shrapnel and shell fragments. It is not proof against penetration by large projectiles.

Squad.—A unit consisting of eight men, four files in double rank. The commander, usually a corporal, is called the squad leader.

Squad column.—A squad in double column of files. See Platoon column.

Staff.—A number of highly trained officers attached to the larger units who are charged with the administration of special departments and who constitute an advisory board to the supreme commander. See General Staff.

Strategy.—The application of the broad fundamental principles of the art of war. The object of strategy is to place troops in the most favorable or least unfavorable position for battle, which is the logical culmination of strategy. Strategy deals with questions of national policy, national resources, geography, mobilization and concentration of troops, supply, transportation, etc.

Successive bounds.—See p. 50.

Successive thin lines.—See p. 328.

Supporting point.—See p. 251.

Supports.—Troops held in rear of the firing line for the purpose of replacing losses, so as to maintain the firing line at proper strength; the large groups on the line of resistance of an outpost; one of the formed bodies of an advance, rear or flank guard.

Tactical walk (or ride).—Tactical instruction given upon the terrain with imaginary troops.

Tactics.—The methods employed in handling troops in battle or in immediate preparation therefor.

Terrain.—An area of ground considered as to its extent and topography in relation to its use for a specific purpose, as for a battle or the erection of fortifications.

Terrain exercise.—A practical problem in tactics prepared for solution on the terrain, with imaginary troops.

Theater of war.—The territory covered by the operations of belligerent forces.

Time fire.—See Fuse.

Trains.—The supply wagons accompanying an army. Combat and field trains are attached to battalions and squadrons and carry respectively, the ammunition and rations of the troops. Ammunition and supply trains are attached to the larger units such as a division. There are also a number of special trains, including sanitary and engineer trains. See Chap. XVII, Division Supply.

Trajectory.—The path of a projectile. Guns of high power are said to have a flat trajectory, that is to say, one which approaches a straight line.

Traverse.—A bank of earth or other material in rear of and perpendicular to the parapet of a trench for the purpose of protecting the occupants from oblique or enfilade fire and to localize the effect of shells bursting in the trench.

Trenches.—The purpose of trenches is to protect the troops occupying them from hostile fire. According to their use they are classified as fire, support and communicating trenches.

Troop leading.—The practical art of commanding troops. Troop leading is often used in contradistinction to decision. The latter involves the formulation of a plan of action, the former the practical technique by which the plan is executed.

Turning movement.—The attack of an enemy, usually on a flank or in rear, by an element of the command widely separated from the remainder of the attacking force.

Visibility problems.—See p. 24.

War game.—A competitive game conducted on a map and involving the tactical handling of troops. The two-sided war game is the usual form, and is carried on by two individuals or groups under the direction of an umpire. In the one-sided war game the umpire dictates the operations of one of the imaginary combatants.

Wire entanglement.—An obstacle of wire or barbed wire strung on posts or other supports; the most commonly employed artificial obstacle.