Drill Regulations iQAST ARTILLERY UNITED STATES ARMY 190 9 FROM THE UNITED STATES GOVERNMENT THROUGH THE SUPERINTENDENT OF DOCUMENTS ^^S.B&9i^~ /iL////o.i g 506 Rev. Stat, prohibits the withdrawal of this book for home use. 7808 Cornell University Library UF453 .A5 1909 Coast artillery drill regulations. Unite olin 3 1924 030 759 579 li Cornell University Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924030759579 COAST ARTILLERY DRILL REGULATIONS UNITED STATES ARMY 1909 WASHINGTON : GOVERNMENT PRINTING OFTICE : 1909 T Wae Department. Document No. 343. Office of the Chief of Coast Artillery. 2 War Department, Office of the Chief of Staff, Washington, April I4, 1909. The following Coast Artillery Drill Regulations liave been approved by tlie President and are publisbed for the informa- tion and government of the Army of the United States and for observance by the organized militia of the United States. By order of the Secretary of War : J. Franklin Bell, Major-General, Chief of Staff. OOI^TEITTS. Chapter I. Page. General principles 9-11 Chapter II. Definitions 12-28 Chapter III. Organization 29-32 Chapter IV. Marching maneuvers 33-36 To form the company 33-35 To march to the battery 35 To post the sections 35-36 Chapter V. The battery— General duties 37-40 CH.iPTER YI. Service at the emplacements 41-104 General instructions 41-43 Mortar battery 43-53 12-inch gun battery, disappearing carriages 53-67 10-inch gun battery, disappearing carriages 67-74 8-inch gun battery, disappearing carriages 74 6-inch gun battery, disappearing carriages 74r-80 12-inch gun battery, barbette carriages 81-89 10-inch gun battery, barbette carriages 89 8-inch gun battery, barbette carriages 89-90 6-inch gun-battery, pedestal mount 90-95 5-inch, 4.7-inch, and 4-inch gun battery 96 3-inch gun battery 96-100 6-pounder gun battery 100-104 Chapter VII. Battery fire-control 105-112 Gun battery of the primary armament 105-109 Mortar battery 109-112 Battery of the intermediate armament 112 Battery of the secondary armament 112 5 6 CONTENTS. Chapter VIII. Page. Bore sighting, orientation, and pointing 113-117 Bore sighting and orientation 113-1 14 Methods of pointing 114-115 Pointing tests 115-117 Chapter IX. Fire and mine commands j 118-122 The fire command 118-120 Fire-control system of a fire command 120-121 The mine command 121-122 Fire-control system of a mine command 122 Chapter X. The battle command 123-125 The battle command 123-125 Fire-control system of a battle command 125 Chapter XI. The artillery district 126-129 Chapter XII. The post 130-133 Chapter XIII. An artillery inspection 134-135 Chapter XIV. Target practice and salutes 136-143 Subcaliber practice 136-137 Service practice 137-139 Battery service practice 139-141 Fire command service practice 141-142 Battle command service practice 142 Modification of practice regulations 142 Reports of target practice '. 142 Salutes 143 Chapter XV Night drill — Searchlights 144-148 Night drill 144 Searchlights 144-148 CONTENTS. 7 Chapter XVI. Pagr.. Communications 149-153 Chaptee XVII. Fire-control apparatus 154-173 Atmosphere board 154 Anemometer 154 Azimuth instrument 154-156 Barometer 156 Deflection board 156-158 Depression position finder 159-161 Mortar deflection board 161 Plotting board 161-163 Powder chart 163-164 Range board 165-170 Telescope - 170-171 Telescopic sight 171 Thermometer 171-172 Wind-component indicator 172 Wind vane 172-173 Chapter XVIII. Care of material 174-192 Chapter XIX. Storage and handling of explosives 193-200 General instructions 193-194 Commercial detonators 194^195 Dynamite 195-196 Explosive D 196-197 Fuses and primers 197 Gun cotton 197-199 Smokeless powder 199-200 Projectiles, filled and fused 200 Chapter XX. Examination for gunners and for special ratings 201-207 Instruction of gunners 201-203 Qualification of rated enlisted men 203-207 COAST ARTILLERY DRILL REGULATIONS, UNITED STATES ARMY. Chapter I. GENERAL FRINCIPLES. 1. Coast defense comprises the military and naval disposi- tions and operations to resist an attack by sea on a coast line. Such attack may take the form of a naval attack, a land attack, or a combined naval and land attack. 8. In the defense of a coast line the functions of the naval forces are normally offensive; those of the land forces, de- fensive. The operations of the naval forces may be and usually are conducted at a distance from the coast line being defended ; those of the land forces are confined to that coast line. Such portions of the naval forces, however, as are not included in the sea-going fleet may be assigned to assist the military forces in the local defense of important harbors. Vessels so assigned are designated as floating defenses, and may include ships of the line, monitors, scouts, torpedo boats, submarine boats, patrol boats, and picket boats. 3. The military preparations for the defense of a coast line usually include — (1) The construction of permanent fortifications and the provision of submarine defenses, manned by coast-artillery troops, for the defense against naval attack of those harbors that are of commercial or strategic Importance. For the protection of the permanent fortifications against capture by small raiding parties landed from an attacking fleet field works are constructed and small bodies of mobile troops as- signed thereto. Troops assigned to this duty are designated as " Coast artillery supports." (2) The assignment of troops of the mobile army for the local defense against land attack of those harbors that are of commercial or strategic importance, and the construction for use in such defense of semi-permanent fortifications or field works. Troops assigned to this duty are designated as the " Coast guard." (3) The mobilization and organization of troops of the mobile army into field armies at points strategically located with respect to the entire coast line. 9 10 GENERAL PRIKCIPLES. 4. The permanent fortifications consist usually of works constructed of earth and concrete with armament mounted therein in fixed positions, together with the accessories neces- sary for the effective service of this armament. The subma- rine defenses consist of submarine mines, automobile torpedoes, and marine obstructions. 5. The armament of the permanent fortifications is classi- fied as primary, intermediate, and secondary. Guns of the intermediate and secondary armament are called rapid-fire guns. 6. The primary armament consists of guns of 8-inch and larger caliber, and 12-inch mortars. These guns and mortars are used to attack armored vessels with shot and shell carrying high explosives. Shell are used at the longer ranges to penetrate thin armor, to silence the secondary batteries, to injure vessels by racking efCect, and to demolish the fire-control stations at more than the battle ranges of naval ships. Shot are used at ranges where the perforation of main armor is possible and are intended to reach the vitals of a ship before explosion. 7. Mortars employ high-angle fire, and are used at all ranges to attack the decks of ships with high explosive shell. 8. The intermediate armament consists of 6-inch, 5-inch, and 4.7-inch guns. This armament is used primarily to attack unarmored vessels, but may be used eflfectively to supplement the primary armament in the attack of armored vessels or the secondary armament in the defense of the mine fields. 9. The secondary armament consists of 4-inch and 3-inch guns. It is used for the defense of the mine fields and to supplement the intermediate armament in the attack of un- armored vessels. 10. The multiplicity of calibers is the result of gradual development rather than of design. The typical guns of the different classes are as follows : Primary : 12-inch or larger guns, 12-inch mortars. Intermediate: 6-inch guns. Secondary : 3-inch guns. ^ 11. For the effective service of the armament the following are necessary : (o) Ammunition, sights, quadrants, loading imple- ments. (6) Fire-control equipment. (c) Power and light equipment. (d) Wireless and other methods of long-distance com- munication. 12. The \inits of the tactical chain of coast artillery com- mand are : The battery. The fire command. — The mine command. The battle command. The district command. GENERAL PRINCIPLES. 11 13. A battery Is a number of guns or mortars of the same caliber and power, grouped with the object of concentrating their fire upon a single target and of being directly com- manded in action by a single individual. The term is used to include also the emplacements in which the guns are mounted and, in a more general sense, the personnel and accessories required to operate it. 14. Batteries are named usually for deceased officers who were killed in action or who were connected with the con- struction of fortifications or the construction and service of their armament. For example : " Battery Shipp," " Battery Parrot," " Battery De Russy," " Battery Barry." 15. A fire command is a group of batteries, generally not more than four, organized for command by a single individual. The batteries composing a fire command should be situated so that their fire covers the same or contiguous water areas. 16. Where it can be avoided, primary, intermediate, and secondary armaments are not grouped in the same fire com- mand, nor are gun and mortar batteries so combined. 17. A mine command consists of the mine groups and the rapid-fire batteries specifically assigned for their protection which are designated for control by a single individual. 18. A battle command consists of all fire and mine com- mands which may be controlled advantageously by one man in the defense of a harbor. Battle, fire, and mine commands are designated by number. 19. A district command consists of those battle commands which are within supporting distance of one another, together with the coast artillery supports assigned to the district. For administrative purposes, forts not within supporting distance may be included in the district. 20. Districts are designated by name, as " The Southern Artillery District of New TorlJ." Chapter II. DEFINITIONS. 21. Aiming. — Pointing the gun by means of a sight. (See Pointing. ) 22. Ammunition hoist. — The device by means of which am- munition Is raised to the loading platform. Separate hoists are used for projectiles and powder, or the latter is served by hand. 23. Ammunition recess. — The space in the parapet wall for the temporary storage of ammunition. 24. Angle of departure. — The angle between the line of de- parture and the line of sight. 25. Angle of fall. — The angle of fall is the angle which the tangent to the trajectory at the point of impact makes with the line of shot. The angle of fall is often expressed as a slope; for example, 1 on 10. 26. Angle of impact. — The complement of the angle of inci- dence. 27. Angle of incidence. — The angle between the line of im- pact and the normal to the surface at the point of impact. 28. Angle of position (or depression). — The angle between the line of sight and a horizontal plane through the axis of the trunnions. 29. Apron. — That portion of the superior slope of a parapet or the interior slope of a pit, designed to protect the slopes against blast. 30. Approaches. — Roadways entering the battery parade. 31. Artillery engineer. — An officer at a coast fort who has charge of the maintenance of all power and electrical ap- paratus. 32. Atmosphere hoard. — A board for determining the atmos- phere reference number. (See paragraphs 617, 749, and 750.) 33. Axis of gun. — The central line of the bore. 34. Axis of trunnions. — The central line of the trunnions. 35. Azimuth of a point. — In coast artillery, the horizontal angle measured in a clockwise direction from south to a line from the observer to the point. For example, the azimuth of a point B from A is the angle (measured clockwise from the south) between the north and south line through A and the line from A to B. The north point has an azimuth of 180°. 36. Azimuth difference. — The difeerence between the azi- muths of a point as read from two other points, 12 DEFINITIONS. 13 37. Azimuth instrument — An iustrument for determiuing azimuths. (See paragraphs 753 to 755, inclusive.) 38. Azimuth setter. — The member of a mortar detachment who lays the mortar in azimuth. 39. Base end station. — ^An observing station at either end of a base line, designed to contain an azimuth instrument or depression position finder. Base end stations are designated as primary, secondary, or supplementary. 40. Base line. — ^A horizontal line the length and direction of which have been determined. This line is used in position finding, especially for long ranges; the stations at its ends are called " base end stations." It is called " right " or " left " handed, depending on whether the primary station is to the right or left of the secondary facing the field of fire. 41. Banquette. — The step between the truck and loading platforms. 42. Battery. — The entire structure erected for the emplace- ment, protection, and service of one or more guns or mortars, together with the guns or mortars so protected. The guns of a battery are grouped with the object of concentrating their fire on a single target and of their being commanded directly by a single individual. 43. Battery commander. — The senior artillery officer present for duty with a battery. 44. Battery commander's station. — An observing station at or near the battery, usually in rear of the center traverse. 45. Battery commander's walk. — The elevated walk leading from the battery commander's station along the rear of the battery. 46. Battery parade. — The area in rear of the emplacements where the sections form. 47. Battle area. — The area covered by the armament of a battle command. 48. Blast slope. — See Apron. 49. Blending. — The process of mixing powders of the same or different lots so as to obtain charges of uniform character- istics. 50. Bore. The interior of a cannon forward of the front face of the breechblock. It is composed of the powder cham- ber, the centering slope, the forcing cone, and the rifled por- tion called the " main bore." 51. Bore-sighting. — In coast artillery, the process by which the line of sight and axis of the bore prolonged are caused to converge on a point at or beyond mid^-ange. (See para- graph 526.) 52. Bourrelet. — ^A swell in the body of the projectile just in rear of the head. 53. Breech. — The mass of metal behind the plane of the bottom of the bore. 54. Breechblock. — The metal plug which closes the breech. 55. Breech mechanism. — The breechblock, obturating device, firing mechanism, and mechanism for operating the breech- block. 14 DEFINITIONS. 56. Breech recess. — The opening which receives the breech- block. 57. Breech reenforce. — The part of the cannon in front of the breech and in rear of the trunnion band. 58. Bursting charge. — The charge of explosive in a projec- tile. 59. Caliber of gun. — The diameter of the bore in inches, measured between diametrically opposite lands. It is the minimum diameter of the rifled portion of the gun. 60. Calibration. — ^Adjusting the range scale so that the range reading at any jsarticular elevation of the gun will Indi- cate the true distance to the center of impact of a group of shots fired from that particular gun and mount at that eleva- tion with the standard velocity and under normal atmospheric conditions. It is desirable to calibrate the guns of a battery under the same atmospheric conditions, although this is not absolutely necessary. It is absolutely necessary that uniform ammuni- tion be used for calibration firing of all guns of a particular battery. When the individual guns of a battery are calibrated the battery is calibrated, for the centers of impact of a series of shots from each gun under normal atmospheric conditions will coincide at the point indicated by any range setting. When guns of a battery "shoot together" (that is, give the same range for the same range setting), they may be fired on the same data, but are not calibrated unless the range under normal atmospheric conditions is that indicated by the range setting. It is not feasible to determine by actual firing all the points of a range scale, and therefore it is assumed that the gun is calibrated when a range scale constructed from a computed range table is adjusted on the gun so as to give the proper setting for a mid-range. 61. Cannon. — Artillery weapons from which projectiles are thrown by the force of expanding powder gases. Cannon are of three classes : Guns, mortars, and howitzers. Guns are long (generally 30-50 calibers), have flat tra- jectories, and are used for low-angle fire (less than 15°), with high velocities (2,000-3,000 f. s., about). Mortars are short (about 10 calibers), and are used for high-angle fire (45°-70°), with low velocities (550-1,300 f. s., about). Howitzers are intermediate between guns and mortars. The term " piece " is used when referring to a cannon of any class. Cannon of the United States land service are classified ac- cording to their use into coast, siege, and field. Cannon are made of a single piece or built up of two or more pieces. 62. Canopy.— The projecting roof over the delivery tables of ammunition hoists of gun batteries. DEFINITIONS. 15 63. Capital. — The line through the gun pintle bisecting the arc of the interior crest. 64. Carriage or mount. — The means provided for supporting a cannon. It includes the parts for giving elevation and direc- tion, for taking up the recoil on discharge, and for returning the piece to the firing position. 65. Carriage, fixed. — A mount provided for guns and mortars in permanent works and not designed to be moved from place to place. 66. Carriage, movable (wheeled mount). — ^A carriage or mount provided with wheels for transportation of the piece mounted thereon. 67. Carriages, coast. — Those used for coast artillery cannon. They may be divided into four classes, depending upon the nature of cover afCorded by the emplacements: (a) Barbette: Where the gun remains above the parapet for loading and firing. (6) Disappearing: Where the gun is raised above the parapet for firing, and recoils under cover for loading, (o) Masking mount: Where the gun remains above the parapet for loading and firing but can be lowered below the level of the crest for concealment. (d) Casemate: Where the gun fires through a port. If the carriage can be traversed so that the gun may be fired in all directions it is said to have all-round-fire (A. R. F.) . If the carriage can not be traversed so that the gun may be fired in all directions, it is said to have limited fire (L. F.). Rapid-fire gun carriages (except the 6-inch on disappearing carriage) are constructed so that the gun recoils in a sleeve and returns to the loading position immediately after firing. Guns of the movable armament are mounted on wheeled carriages. 68. Case I — Case II — Case III. — (See Pointing.) 69. Casemate electrician. — The member of a mine command assigned to the care and operation of the mining casemate. 70. Charge. — The powder and projectile. The powder for large cannon to include 4.7-inch guns is separate from the projectile. For smaller calibers the projectile and powder are not separate ; such ammunition is called " fixed." 71. Chase. — The part of the gun in front of the trunnion band. 72. Chief of ammunition service. — A noncommissioned offi- cer in charge of the magazines, galleries, and service of am- munition for a gun battery, or a mortar emplacement. 73. Chief loader. — A noncommissioned officer of a mine com- pany in charge of loading submarine mines. 74. Chief planter. — ^A noncommissioned officer of a mine company in charge of the service on a mine planter. 75. Clinometer. — An Instrupent for measuring accurately the inclination of the axis of the bore to the horizontal. 16 DEFINITIONS. 76. Clinometer rest. — The support for a clinometer inserted in the muzzle of the gun ; also called " bore plug." 77. Coast artillery fort. — The coast defenses at any military post and the personnel assigned thereto. 78. Coast artillery garrison. — The personnel, to Include regu- lar coast artillery, coast artillery reserves, and coast artillery supports, assigned to a coast artillery fort. 79. Coast artillery reserves. — Troops of the organized militia organized as coast artillery for the purpose of supplementing the regular coast artillery in time of war. 80. Coast artillery supports. — Infantry troops assigned to coast artillery forts to support the artillery in repelling land attacks in the immediate vicinity of the fortifications. 81. Communications. — Means of transmitting orders and messages through the tactical chain of command. (See Chap- ter XVI.) 82. Computer. — A member of the fire-control section who operates a range or deflection hoard. 83. Corrected range. — The fictitious range which determines the elevation to be given the gun. 84. Corridor. — The passageway in rear of a traverse con- necting two adjacent emplacements, at the loading platform level. 85. Corridor wall. — The traverse wall along the corridor. 86. Counterweight. — The weight used in bringing a gun on a disappearing carriage or masking parapet mount to the firing position. The pit in the gun platform for the reception of the counterweight of a disappearing carriage is called the counter- weight well. 87. Cover posts. — Positions for the members of a mortar de- tachment at the command TAKE COVER. 88. Crane. — ^A mechanical device for raising ammunition by means of differential or other blocks. 89. Danger space. — The horizontal distance within which a target of a given height would be hit by a projectile. The danger space varies with the range, the flatness of the tra- jectory, the height of the target, and the height of the gun above the target. The maximum range which is all danger space is called the " danger range." 90. Deflection. — The horizontal angle between the plane of sight and plane of departure; it is expressed as a reference number, and is set off on the sight deflection scale. 91. Deflection board. — ^A device for the purpose of deter- mining the reference numbers for the deflection scale of the sight in Cases I and II, and the azimuth correction reference number in Case III ; and, for mortars, the corrected azimuth. (See paragraphs 757 to 768, inclusive.) 92. Delivery table. — The table from which ammunition is delivered to the truck. 93. Density of loading. — The mean density of the whole contents of the powder chamber. It is the ratio of the weight DEriNITIONS. 17 of the powder charge to the weight of a volume of distilled water (temparture of 39.2° F.) which will fill the powder chamber. The formula for computing it is A (density of loading) = (27.7 W) /V, in which IF is equal to the weight of the powder in pounds and T' the volume of the chamber in cubic inches. 94. Depression position finder. — ^An instrument to determine the range and azimuth of a target, the ranges corresponding to different angles of depression being indicated on the instru- ment. (See paragraphs 769 to 779, inclusive.) 95. Deviation. — Distances measured either in the horizontal plane at the level of the target or in a vertical plane through the centei' of the target at right angles to the plane of direction. If from the point of impact of a shot a perpendicular be drawn to the plane of direction, the length of this perpendicular is the lateral deviation, and it is plus or minus according as the point of impact is to the right or left of the line of direc- tion looking from the gun. The distance from the foot of this perpendicular to the center of the target is the longitudinal deviation. It is plus when the point of impact is beyond the target, and minus when it is short. 96. Deviation at the target. — If from the target a line be drawn perpendicular to the plane of direction intersecting the plane containing the line of shot, the length of this perpendicu- lar is the " deviation at the target." 97. Deviation, absolute. — The distance measured in a straight line from the center of the target to the point of impact. 98. Deviation, mean lateral. — The arithmetical mean of the lateral deviations of the points of Impact of a series of shots. 99. Deviation, mean longitudinal. — The arithmetical mean of the longitudinal deviations of the points of impact of a series of shots. 100. Deviation, range. — The difference between the range to the target and the range to the point of impact. 101. Directing point. — ^A point at or near the battery for which relocation is made at the plotting room. It is the point over which the gun center of the plotting board is adjusted. When the pintle center of a gun is taken as the directing point, such gun is called the " directing gun." 102. Displacement of any point. — The horizontal distance in yards of that point from the directing point. 103. Drift. — The divergence of the projectile from the plane of departure due to the rotation of the projectile, its ballistic character, and the resistance of the air. It is generally in the direction of rotation, except for extreme elevations of high- angle fire, in which case it may be opposite to the original direction of rotation. For the United States service rifled guns it is to the right. It may be expressed either in yards or angular measure. 82615—09 2 18 DEFINITIONS. 104. Elevation. — A general term to denote the inclination in a vertical plane given to the axis of the gun in pointing; the angle between the axis of the gun and the line of sight is the sight elevation ; the angle between the axis of the gun and the horizontal is the quadrant elevation. 105. Elevation setter. — The member of a mortar detachment who lays the mortar in elevation. 106. Emplacement. — That part of the battery pertaining to the position, protection, and service of one gun, mortar, or group of mortars. 107. Emplacement hook. — A book containing all necessary data concerning the battery. 108. Energy of the projectile. — The energy stored up in the projectile by the force of the expanding gases generated by the explosion of the powder charge. It is expressed usually in foot-tons. The formula for computing it is : ^=1^1-7(4480^), in which W is the weight of the projectile in pounds, 1" its velocity in feet per second, and g the acceleration due to gravity (mean value 32.10). 109. Equalizing pipe. — A pipe connecting corresponding ends of two recoil cylinders for the purpose of equalizing the pres- sure therein. 110. Exterior crest. — The line of intersection of the superior and exterior slopes. 111. Exterior slope. — The outer slope of the battery. 112. Field of fire. — The area covered by the armament of a battery. 113. Fire area. — The area covered by the armament of a fire command. 114. Fire-control. — Fire-control is the exercise of those tac- tical functions which determine — (o) The objective of Are. (6) The volume and concentration of fire. (c) The accuracy of fire. The term " fire-control system " includes the means em- ployed in fire-control, the scheme of its installation, and the method of its use. The material as installed, which is employed in the fire-con- trol of a battery or district, is called the " fire-control installa- tion " for that battery or district. Installations are either standard or provisional. 115. Fire-control material may be classified under the fol- lowing heads : (a) Instruments for the observation and location of targets. (h) Instruments for the determination of firing data. (c) Communications. The personnel employed in fire-control is called the " flre- control personnel." DEFINITIONS. 19 116. The fire-control stations for the coast artillery service and the conventional signs and abbreviations therefor are as follows : station. Battle commander's station Primary station of a fire command Secondary station of a fire command Supplementary station of a fire command Primary station of a battery Secondary station of a battery Supplementary station of a battery Emergency station of a battery Primary station of a mine command Secondary station of a mine com m and Supplementary station of a mine command. . . Double primary station of a mine command.. Double secondary station of a mine command Separate observing room Separate plotting room Battery commander's station Meteorological station Tide station Searchlight Post telephone switchboard Signal station Wireless station Abbrevia- tion. C F' F" F'" B' B" B"' E M' M" M"' M'-M' M"-M" O P B.C. Met. T S P. S. B. ss ws Sign. ® [53 © I M"|-M" I ® \u\ T| H W 'ixf JS_ M &c. 20 DEFINITIONS. 117. Tiring interval. — The interval of time between con- secutive shots from the same gun or mortar in continuous firing. 118. Fixed light.— A searchlight used to Iceep the outer limit of the battle area illuminated. 119. Forcing cone. — The part of the bore immediately in front of the centering slope. It is formed by cutting away the lands so as to decrease their height uniformly from front to rear. 120. From battery. — The position of a gun when withdrawn from its firing position. 121. Gallery. — Any passageway covered overhead and at the sides. 122. Gas check. — The essential mechanical features of an obturator which enable it to prevent the escape of gas. 123. General defense plan. — Scheme of defense formulated prior to an attack. A variety of these plans, based on the character of attack to be expected, should be prepared and issued to the command. 124. Groove. — See Eifling. 125. Gun commander. — A noncommissioned officer who com- mands a gun section. The rated gun commanders authorized by law when assigned in command of mortar pits are called "pit commanders;" of ammunition sections, "chiefs of ammu- nition service." 126. Gun company. — A company assigned to the service of direct-fire guns only. 127. Gun differences. — Differences in range and azimuth to the target from the gun and from the directing point, due to gun displacement. 128. Gun displacement. — The displacement of the pintle cen- ter of the gun. 129. Gun platform. — That part of the battery upon which the gun carriage rests. 130. Gun pointer. — The member of a gun section who con- trols the aiming of a gun or laying it in azimuth (Case III), or the chief of a mortar detachment who supervises the load- ing and laying of a mortar. 131. Hoist room. — The room in the battery containing the receiving table of the ammunition hoist. 132. Hoop. — A cylindrical forging superposed upon the jacket or other hooiis. 133. Identification of a target. — The act or process of recog- nizing a target which has been designated. 134. Illuminating light. — A searchlight whose primary func- tion is to follow a target that has been assigned to a Are command. 135. In battery. — The position of a gun when ready for firing. 136. In commission.— The term to indicate those batteries to which personnel is assigned. 137. Indication of a target. — Any method employed to designate a target. DEFINITIONS. 21 138. In service. — The term to indicate those batteries to which personnel is assigned and at which dally drills are held. 139. Interior crest. — The line of intersection of the interior slope with the superior slope. If there be no Interior slope, it is the line of intersection of the interior wall and superior slope. 140. Interior slope. — The inner slope of a parapet connecting the interior wall and superior slope. 141. Interior wall. — The inner parapet wall. 142. Jacket. — A cylindrical forging, generally extending from the breech of a cannon to a plane beyond the trunnions. 143. Jump, angle of. — The angle between the line of de- parture and the axis of the bore when the piece is pointed. In determining the sight or quadrant elevation to be used, this angle must be applied as a correction to the angle of departure given In the range table ; this correction differs for different guns, carriages, and ranges, and may be determined by experiment. 144. lands. — See Rifling. 145. Land front. — Those portions of the defenses which are provided to repel an attack from the land area in rear of or on the flank of permanent seacoast works. 146. laying. — Pointing the gun without the use of a sight. (See Pointing.) 147. Line of departure. — The direction of axis of the bore when the projectile leaves the muzzle. 148. Line of direction. — The line from the gun to the center of the target at the instant the shot strikes. 149. Line of impact. — The line tangent to the trajectory at the point of impact. 150. Line of shot. — The line from the gun to the point of impact. 151. Line of sight. — The straight line passing through the sights of the piece; at the instant of firing this line passes through the target. 152. Loading platform. — That surface upon which the can- noneers stand while loading the piece. 153. Loading position. — ^At gun batteries; breech closed, can- noneers at posts for inspection, projectile and powder charges on truck near delivery table. At mortar batteries ; mortars horizontal, breech closed, cannoneers, except Xo. 6, at posts for inspection, projectiles on trucks about 10 feet in rear of mortars, powder at entrance to pit. No. 6 is at the entrance to the powder magazine. 154. Loading tray. — A device used to protect the breech re- cess while loading. 155. Location of a target. — The determination of its range and azimuth from some given point. Having the location of a target from one point, the process by which its range and azimuth from some other point are determined without further observation is called " relocation." 156. Machine guns. — Guns of one or more barrels using fixed ammunition and provided with mechanism for continu- 22 DEFINITIONS. ous loading and firing. The mechanism may be operated by man power or by the force of recoil. Guns in which the force of recoil is used to operate the breech block are termed " semi-automatic." When this force is used also to load and fire the guns, they are termed " automatic." 157. Magazines. — Rooms for the storage of powder, primers, fuses, etc. 158. Manning party. — The personnel assigned to the service of any specific element of the defense. 159. Manning table. — A list of the names of those who con- stitute a manning party, with the particular post to which each is assigned. 160. Meteorological message. — The message sent to fire com- manders by a meteorological observer. It includes the barom- eter and thermometer readings, the atmosphere reference number, and the velocity and azimuth of the wind. 161. Mine (submarine). — A case containing a charge of ex- plosive and appliances for firing it, to be fixed in position beneath the surface of the water. 162. Mine company. — Company assigned to the service of submarine mines. 163. Mine field. — Area of water in which submarine mines are planted. 164. Mortar company. — ^A company assigned to the service of mortars. 165. Muzzle. — The front end of a cannon. 166. Muzzle velocity. — The velocity of the projectile as it leaves the muzzle. 167. Observer. — A member of the fire-control section who is in charge of and uses an observing Instrument. 168. Observing interval. — The time in seconds between two consecutive observations on a target. 169. Observing station. — A position constructed in a favor- able place for observing the field of fire. 170. Obturator. — Any device for preventing the escape of gas. Obturation is the process of preventing the escape of gas. 171. Occult. — To shut ofi! the beam of a searchlight. 172. Orders of fire. — First. Unrestricted fire. — When the only limitation im- posed by the fire commander upon the action of a battery is the assignment of a target the fire is said to be unrestricted. This is the normal fire action of a battery. Second. Restricted fire. — When the range at which to fire, the number of shots, the firiiif; interval, or any other limitation except as to target, is imposed upon the action of a battery, the fire is said to be restricted. In unrestricted fire, and also in restricted flre when the rate is not specified, the fire should be as rapid as possible. 173. Orientation. — The process of adjusting an instrument, gun, or mortar in azimuth. DEFINITIONS. 23 174. Orientation table. — ^A table showing tlie azimuths and distances of various points in the harbor. 175. Parados. — A structure in rear of a battery for protec- tion against fire from the rear. It may have interior, superior, and exterior slopes. 176. Parade slope. — The rear slope or wall of an emplace- ment. 177. Parapet. — That part of a battery which gives protection to the armament and personnel from front fire. 178. Pit. — That part of a mortar emplacement designed for mounting one or more mortars, usually four. 179. Pit commander. — A noncommissioned officer (gun com- mander) in charge of a mortar pit. 180. Plane of departure. — The vertical plane containing the line of departure. 181. Plane of direction. — The vertical plane containing the line of direction. 182. Plane of sight. — The vertical plane containing the line of sight. 183. Plotter. — A member of the fire-control section in charge of the plotting. 184. Plotting board. — A board for the purpose of plotting the track of a ship and, in connection with range and deflection boards, determining the corrected data for firing. (See para- graphs 782 to 791, inclusive.) 185. Plotting room. — ^A room in which the plotting detach- ment works. 186. Pointing. — The operation of giving the direction and elevation necessary to hit the target. When the sight is used it is called " aiming ;" when the sight is not used, it is called " laying." There are three cases of pointing — Case I. When direction and elevation are both given by the sight. Case II. When direction is given by the sight, and eleva- tion by the range scale on the carriage. Case III. When direction is given liy the azimuth scale and elevation by quadrant or by the range scale on the carriage. 187. Point of fall. — ^The point where the trajectory pierces the horizontal plane through the muzzle of the gun. 188. Point of impact. — The point where the shot strikes. 189. Position fi.nder. — An instrument for locating a target. The position finding system used, in our service includes — (1) The horizontal base system, which employs azimuth reading instruments in stations at the ends of a base line, and a plotting board. (2) The D. P. F. system, which employs a depression position finder and a plotting board. (3) The emergency system, which ordinarily employs a self-contained instrument located at the battery, with or without a plotting board. 24 DEFINITIONS. 190. Powder chamber. — The portion of the bore for the re- ception of the powder charge. It is composed of the main chamber and a conical part (the centering slope), which unites the chamber with the forcing cone. The centering slope serves to bring the axis of the projectile to the axis of the bore. 191. Powder chute. — ^An Inclined shaft for returning car- tridges or dummies to the magazine. 192. Powder hoist. — A device for raising powder to the loading platform. 193. Powder hoist well. — The shaft through which the pow- der hoist operates. 194. Predicted point. — The point located on the plotting board at which it is estimated a target will arrive at the end of an assumed interval of time. This interval of time is called the " predicting interval." 195. Predicted time. — The time at which a target should reach the predicted point. 196. Predicter. — An accessory of the mortar plotting board used to locate the position of the predicted and set-forward points. 197. Primary station. — See base end station. 198. Primer. — ^A small tube containing materials which are ignited readily by friction, by percussion, or by an electric current. It is used to ignite the powder charge. 199. Priming charges. — Small charges of black powder in the ends of powder sections necessary for the ignition of smokeless powder. 200. Quadrant. — ^An instrument for giving quadrant ele- vation. 201. Quadrant elevation. — The angle between the horizontal and the axis of the bore when the piece is pointed. 202. Ramp. — An inclined plane serving as a means of com- munication from one level to another. 203. Range. — In a limited sense, the horizontal distance from the gun to the target. In a general sense it is applied to horizontal distances between position iinder and target, position finder and splash, gun and splash, etc. The range of a shot is the horizontal distance from the center of the gun to the point where the projectile first strikes. 204. Range-azimuth table. — A table of ranges and the cor- responding azimuths from a gun to points in the center of the main ship channel or channels. It is kept at the gun and used for firing without the use of range-finding apparatus. 205. Range board. — A device for determining the range cor- rections which must be made for wind, atmosphere" tide, velocity, and travel of target during the observing interval and time of flight. (For nomenclature, adjustment, and use, see paragraphs 797 to 815, inclusive.) 206. Range difference. — The difference in range of a point from any other two points — as the difference between the ranges of a target from two guns of a battery. 207. Range finder. — Au instrument for determining ranges. DEFINITIONS. 25 208. Range keeper. — The member of the fire-control section who operates a time-range board. 209. Range officer. — The officer in immediate charge of all or a part of the flre-control section. 210. Range setter. — The member of the gun section who lays the gun for range. 211. Rapid-fire gun. — ^A single-barrel breech-loading gun provided with breech mechanism, mounting, and facilities for loading, aiming, and firing with great rapidity. The breech mechanism is operated by a single motion of the handle or lever. The smaller calibers use fixed ammunition. 212. Ready. — At gun batteries, a signal given to indicate to the gun pointer that the piece is ready to be fired. At mortar batteries, a signal given to the battery commander that the mortars are ready to be fired. 213. Rear slope. — The slope to the parade in rear of the battery. 214. Receiving table. — The hoist table on which ammunition is placed preparatory to raising. 215. Recoil. — The backward movement of the gun on firing. Counter recoil is the return of the gun in battery. 216. Recoil cylinder. — The hydraulic cylinder for controlling the recoil. 217. Reference number. — An arbitrary number used to avoid " plus " and " minus," " right " and " left " in data for firing. 218. Relay. — The command given when mortars are not to be fired as laid, but are to be fired on the next data furnished. 219. Reserve table. — A table In a sheltered position for re- serve ammunition. 220. Restricted fire. — See orders of fire. 221. Rifling. — Helical grooves cut in the surface of the bore for the purpose of giving a rotary motion to the projectile. The rib of metal between two adjacent grooves is called a " land." 222. Rimbases. — The masses of metal uniting the trunnions with the trunnion band. 223. Round. — One shot from each piece of a battery. 224. Roving light. — A searchlight, the primary function of which Is the detection of vessels in or approaching the battle area. 225. Salvo. — A round fired simultaneously from a mortar pit or battery, or from a gun battery. 226. Salvo point. — A selected point at which fire is to be concentrated. 227. Salvo table. — A table giving ranges and azimuths of salvo points. 228. Searchlight area. — The area of land or water illumi- nated by a searchlight. 229. Searchlight range. — The maximum distance at which a target can be illuminated sufiieiently for range finding and identification purposes. 230. Secondary station. — See base end station. 26 DEFINITIONS. 231. Serving table.— A table for keeping a supply of project- iles convenient to the breech during loading. It is usually mounted on wheels. 232. Set-forward point.— A point on the course of a target in advance of the predicted point, located by laying ofC from the predicted point a distance equal to the travel of the target in the time of flight. 233. Shell room. — ^A room for the storage of projectiles. 234. Shell tracer. — An attachment to the projectile enabling its flight to be followed. Both day and night tracers may be used. 235. Shot gallery. — A gallery for the storage of projectiles. 236. Shot hoist. — A device for raising projectiles from the lioist room to the loading or truck platform. 237. Shot hoist well. — The shaft through which the project- ile hoist operates. 238. Sight. — An instrument by which the gun pointer gives the gun the proper direction for firing. Sights are of two classes, open and telescopic ; the former consists of two points which are brought into line with the target by the unaided eye; the latter uses the magnifying power of the telescope and is the standard sight. (See paragraph 821.) 239. Sight elevation. — The angle between the line of sight and the axis of the bore when the piece is pointed. 240. Striking angle. — The angle which the line of impact makes with the horizontal plane. It is equal to the angular depression of the point of impact plus the angle between the line of impact and the line of shot. 241. Striking velocity. — The velocity of the projectile at the point of impact. 242. Superior slope. — The top slope of a parapet or traverse. 243. Supplementary station. — See base end station. 244. Swell of the muzzle. — The enlargement of the exterior of the gun at the muzzle. 245. Tactical command. — Command at drill and during ac- tion. 246. Tactical responsibility. — Responsibility for all matters affecting the efficiency of a tactical command. 247. Targ. — The piece of metal used to indicate the intersec- tion of the arms on the plotting board. 248. Target. — The object at which guris or mortars ' are pointed. 249. Telescopic sight. — See paragraph 821. 250. Throttling bar. — A bar in the recoil cylinder to regu- late the size of the orifice through which the oil escapes from one side of the piston head to the other. 251. T-I bell. — A bell to indicate the observing interval. 252. Time-range board. — A board to show range at any in- stant. It is placed on the emplacement wall and operated on data from the plotting room. 253. Tracking. — The processes by which successive positions of a moving target are plotted on a chart. It includes the DEFINITIONS. 27 observations by the observers at the position-finding instru- ments, plotting the results of these observations on the plot- ting board, and tracing thereon the plotted track of the target. < Q_ 254. Trajectory. — The curve described by the center of grav- ity of the projectile in passing from the muzzle of the gun to the point of impact. ( See fig. 1. ) 255. Travel of projectile. — The distance from the base of the projectile in its seat to the muzzle of the gun. 28 DEFINITIONS. 256. .Travel of target. — The distance passed over by the tar- get in the time of flight. It is also used to express the dis- tance passed over by the target in an observing interval. 257. Traverse. — The structure protecting the armament and personnel from flank fire. 258. Traversing indicator. — ^A device used by gun pointers to control the traversing of a gun without command. 259. Trial shots. — Shots flred before practice or action to determine — for guns, the muzzle velocity to be used; for mortars, the range and deflection corrections to be applied. 260. Trolley. — A mechanical device for transporting pro- jectiles on horizontally suspended tracks. 261. Truck platform. — If the ammunition trucks run on a different surface from that of the loading platform, this sur- face is called the " truck platform," 262. Truck recess. — The spaces in the parapet wall for the storage of ammunition trucks. 263. Trunnions. — The cylinders which rest in bearing sur- faces of the carriage called " trunnion beds." Their axis is perpendicular to the axis of the bore and ordinarily in the same plane ; they connect the gun with the carriage and trans- mit the force of recoil from one to the other. The faces of the trunnions are the end planes perpendicular to their axis. 264. Trunnion band. — The hoop of which the trunnions form a part. 265. Tube. — The inner portion of a built-up gun extending usually from the breech to the muzzle. 266. Twist of rifling. — The inclination of the grooves to the axis of the gun at any point. When this inclination is con- stant the twist is uniform ; when it increases from the breech to the muzzle it is increasing. Twist is generally expressed in turns per caliber, e. g., one turn in 40 calibers, meaning that the projectile makes one complete revolution in passing over a length of bore equal to 40 calibers. 267. Unrestricted Are. — See Orders of fire. 268. Vent. — A small channel leading from the exterior to the powder chamber for ignition of the powder charge. 269. Water front. — That portion of the defenses bearing upon the navigable water areas that may be open to an enemy. 270. Wind component indicator. — ^A device for determining the reference numbers corresponding to the transverse and longitudinal components of the wind. ( See paragraphs 824 to 828, inclusive.) 271. Zone. — In mortar firing, the area in which projectiles fall for a given chiirge of powder, when the elevation is varied between the minimum and maximum. It is also used with reference to other portions of the de- fensive area, as " outer defense zone," " inner defense zone," etc. Bfittle commander. Searchlight nthcer. Oommimii'iition officer. Fire commander (guns). Communication officer. Fire commander (gnni) . ComiuuniCBition officer, i Battery commander. Battery commander. Battery commander. Battery cAmmauder. Kire commander (mortars). t'ommunication officer. Mine (.-ommander. Battery commander. Batterv commander. Assistant ("oniniuiiicttlion liattery roinnmndcr. mini' conimander. officer. Range Kmplacement Range Kmplaceraent RHUge Kmplacement Range Kinplaceuient As-sistant, liangi' KiiiiiUu-emi'iit l':mpla(-'ement Assistunt Range Kmplarement Kmplacement officer. officer. officer. officer. officer. officer. officer. ->p Screw, Tye Le Cye Rec /Yoke Cap Telescope Trunnion fbcu5ir-)g Knob Ly, Eve Rece Adapter Crosswire Holder and Adjusting Screws —Objective and Objective Cell Worm Adjusting Screw Worry-\ Box Elccentrii Crank Vorm Bov Adjusting 5crew -Worm Sot 'Worm Screw Dix Crank Fig. 3. 82013 — 00. (To face page 156. 1 Q < O CD o UJ Q •I- FIRE-COXTEOL APPARATUS. 157 deflection to be set on the sight is indicated on the proper scale of the instrument. 758. The instrument consists of a base B. figure 4, upon which slides a movable frame A, called the platen ; this frame slides on the rod C, to which It is attached by means of two lugs XN. In the left-hand lug there is a set screw M, by means of which the platen may be clamped to the rod C. The rod C is attached to the base by the two brackets K and Q. In the bracket K is a threaded sleeve L, which can be turned by the milled head J, thus giving a slow motion to the rod, and consequently to the platen. Attached to the base at the lower side are three scales. Two of these, the deflection scale and travel scale, are fixed, and the azimuth correction scale is movable. (The travel scale is no longer needed In the use of the board.) On the left-hand side and attached to the base is the wind arm P and the wind arc G. Attached to the platen is the platen scale I, over which moves the travel arm D. The scale I can be given two posi- tions on the platen, one corresponding to a time interval of 1.5 seconds and one to a time Interval of 20 seconds. (The latest boards are made for observing intervals of 15 and 30 seconds.) Over all moves the T square E, which also slides on the rod C. On the face of the T square there is a range scale called the T square scale. Attached to the left side of the platen is a piece of metal H, called the leaf. The curved edge of the leaf Is a drift curve. On the left there is a range scale, which is used In setting the platen for wind and drift. This is called the leaf range scale. 759. Platen scale. — This is a scale representing travel In azimuth ; it is graduated in degrees and hundredths, scale one-half of a degree to the inch. It is numbered from left to right, and the reference number at the origin Is 15°, to corres- pond to the azimuth degree tally dial on the plotting board. 760. Deflection scale. — This scale indicates the deflection to be used on the sight in Case II, scale of half of a degree to the inch. It is numbered from left to right, with 3° in the center to correspond to the reference numbering on the sight scale. 761. Azimuth correction scale. — This scale indicates the cor- rection to be applied to the gun arm on the plotting, board In Case III. The scale is one-half of a degreee to the Inch, and it is numbered from left to right with 15° in the center to correspond to the numbering of the azimuth correction scale on the gun arm. 762. The wind arc. — The arc is graduated for wind compo- nents varying by 10 miles per hour. The origin (zero wind) is the graduation numbered 50, and the corresponding position of the wind arm is normal, that is, perpendicular to the de- flection scale. The reference number zero corresponds to a left wind component of 50 miles per hour. The reference 82615—09 11 158 FIRE-COJ«TEOD APPARATUS. number 100 corresponds to a right wind component of 5u miles per hour. The wind arm is set to the proper reference num- ber by the arrow index. 763. T-square scale. — This scale, although graduated in yards of range, is a scale of times of flight. The range num- bers are placed at a distance from the zero of the scale cor- responding to the time of flight for the range. The time scale is five seconds to the inch. The origin of the time scale for the board is the center of motion of the travel arm. 764. The leaf range scale. — This is a non-equicrescent scale constructed so that the correction for wind and drift is ap- plied by a single setting. 765. For suhcaliber practice. — A special leaf scale and scale arm for the T-square are used. When not supplied paper scales should be constructed. Operation. 766. First. Set the wind arm to the proper reference num- ber, as indicated by the wind component board. Second. Set the platen so that the point of the drift curve corresponding to the range will be accurately over the right- hand edge of the wind arm. Third. Set the travel arm (right edge) for travel reference number as received from the plotting board. Fourth. Set the azimuth correction scale so that the travel reference number is under the normal of the deflection scale. Fifth. Set the T-square so that the point of its scale corre- sponding to the range will be accurately over the right edge of the travel arm. The bevel edge of the T-square then indicates : (o) On the deflection scale the deflection to be used on the sight with Case I or II. (6) On the azimuth correction scale the 'correction to be applied to the gun arm, when using Case III. 767. The foregoing operation, when used for Case III, is based upon the assumption that the guns can be laid continu- ously for azimuth as well as for range and can be flred when ready. With guns on disappearing carriages there is a delay in traversing while the truck is at the breech, but experience has shown that a well-trained detachment can pick up the time azimuth relation easily while the breech is being closed and the gun going in battery. 768. For use with systems of firing at a predicted point which require more than one observing interval to lay the gun in azimuth two multiplying scales are furnished with each board to be attached to the semicircular brace of the platen. One of these scales is intended for use when a fifteen- second interval is employed and the other with a twenty-second interval. They permit the making of allowance for travel during time of flight plus the travel during two observing intervals. FIRE-CONTBOL APPARATUS. 159 All of the operations are the same except the fourth, which reads as follows : Fourth. Set the azimuth correction scale to the reading of the multiplying scale. DEPRESSION POSITION FINDEE. 783. Depression position finders are instruments for deter- mining the position of an object by means of its azimuth and range. The azimuth features are similar to those described in paragraphs 753 and 754. The range is determined by meas- uring the angle between the horizontal and the line from the instrument to the water line of the object, the measure of the angle being read directly from the Instrument as the range. In addition to accurate setting of the Tertical wire for azi- muth, as in the case of azimuth instruments, the horizontal wire must be set accurately upon the water line of the object observed. Adjustment of the Swasey D. P. F. 770. 1. Level the instrument carefully (par. 754). 2. Focus the telescope (par. 820). 3. For reading azimuth angles the instrument must be oriented by setting the azimuth of a known point on the scale and bringing the vertical wire exactly on the point by means of the azimuth adjusting screws. The holding down bolts for the base are situated so that the Instrument is oriented approximately when the base is placed properly on the bolts. 4. The adjustment for reading ranges in made as follows : (It is assumed that datum points at short, mid, and long range, Dl, D2 and D3, have been established.) (a) Set the height scale to Indicate the height of trunnions of the instrument corrected for tide. (6) Set the range drum to read the range of D3 and direct the telescope on that point; water line by means of the micrometer screw. (c) Set the range drum to the range of Dl, turn the tele- scope on it and water line by moving the top carriage along the height scale by means of the carriage knob. (d) Repeat (6) and fc) until the adjustment permits ap- proximately correct readings on Dl and D3. (e) Then test on D2; should the difference between the range reading and the true range be small, no change in adjustment need be made. Should this difference be material, D2 should be substituted for D3 or Dl in (6) and (c) de- pending on the range at which the instrument is to be used ; (for D] if a longer and for D3 if a shorter range than D2). 771. This adjustment once made, should be checked from time to time. 160 riEE-CONTEOL APPARATUS. 772. Wbere no datum points liave been established, the method of adjustment is similar to that given above by making use of buoys or other fixed objects that can be vs'ater lined and the ranges to which have been determined previously by the horizontal base system. As far as practicable they should be at long, mid, and short ranges, corresponding to Dl, D2, and D3 above. 773. If reference marks have been established on one or more datum points, set the height scale for the height of the trunnions of the instrument above the reference mark, and with the range drum set to read the correct range make the horizontal wire coincide with the reference mark by means of the micrometer. Set the height scale index to indicate height of the trunnions of the instrument corrected for tide and proceed as in (6"), (c), and (d) above, or if the tide is not known, water line as in (c), and repeat (6), (c), and (d) as before. Adjustment of the Lewis D. P. F., model 1901. 774. The Lewis D. P. F., model 1907, consists of a pedestal on which are mounted two trains of gears which operate re- spectively the range and azimuth scales. The inclination of the telescope is given by means of a double screw, which insures constant parallelism of the graduated arm on which the height scale is laid off and which transmits the motion of the screws directly to the telescope. The index slide on the height scale carries a refraction screw. 775. To correct automatically for a variation in height a cam attachment operates a slotted bar which is connected with the refraction screw. 776. Rapid changes in azimuth are made by turning the upper plate of the instrument, the friction of the gear not offering enough resistance to prevent this ; slow changes in azimuth are made by turning the azimuth head. 777. This instrument has three leveling screws. To level it: Set one of the levels over two of the screws and turn the screws in opposite directions until the bubble is in the middle. Bring the bubble of the other level to the middle by means of the third leveling screw alone. Turn through 180 degrees and correct as provided in paragraph 754. 778. When the Instrument is leveled but one adjustment for range reading is necessary. This is made as follows : Set the height scale to correspond to the height of the trunnions of the Instrument corrected for tide. Set the range scale to the range of a datum point, preferably one at mid-range. 'Water- line the datum point by means of the refraction screw. 779. For reading azimuth angles the instrument must be oriented by setting the azimuth of a known point on the scale and bringing the vertical wire exactly on the point by means of the spanner wrench provided for turning the instrument on the pedestal. PL0TTIN6 BOARD. \ndm% for- reatiimo hundredths of Degree, Connecting Bar lnde« Clamp ndej Olst Inde* Knob SiOir.— 00. (To taoo page IGl. Heading Window for even Decrees /vy. 6. Oun Arn-i Azin-iurh oub-Scale FIRE-COXTEOL APPAKATTJS. 161 MOBTAE DEFLECTION EOABD. 780. The mortar deflection board is illustrated in Figure 5. It consists of a cylinder A, on the elements of which are num- bered, consecutively, azimuths from 1° to 21°, from 11° to 31°, etc., the last series running from 351° through 0° to 11°. The degi-ees only are on the cylinder, the azimuth subscale B giving the subdivisions to 0.05°. Any desired series may be brought into the slit on the shield R by turning the head K. Immediately below the subscale B is the drift scale C on the drift-scale slide D', which is carried by the carriage D. The carriage is moved by turning the main traversing wheel E. There is a pointer H on the carriage for setting to any azi- muth on the subscnle. The carriage I may be moved by the head K independently of the carriage D. On the carriage I there are two pointers, the first, L, for setting the elevation on the drift scale C, the second, M, for indicating the corrected azimuth on the subscale B. The pointer JI may be given an independent motion by the head X ; the amount of this motion Is indicated on the deflection scale P by the pointer Q. 781. The construction of the board depends upon the theory that the angular drift is constant for a given elevation what- ever the velocity. Its operation is as follows : Set the pointer H to the plotting-board azimuth of the set-forward point, bringing the proper degrees on the cylinder into view by means of the head X. Set the pointer L for the elevation as deter- mined from the plotting board. If no arbitrary correction as a result of observation of fire is to be made, set the pointer Q to 3°, the normal of the deflection scale. The pointer JI now indicates the azimuth of the set-forward point corrected for drift. Arbitrary corrections may be made at any time by setting Q to the proper reference number. PLOTTING BOARD. Orientation of the board and gun arm center. 782. The base-line arm may be moved through 1 degree either way and set to the proper reading by means of verniers attached to each end. The zero of the fixed scale of the vernier on the main azimuth circle opposite the vernier on the base-line arm may be assumed to correspond to any convenient degree number, depending upon the azimuth of the base line. It is convenient to consider the zero opposite one end of the base-line arm as corresponding to the nearest degree of the back azimuth (180° -|- the azimuth). For example, assume that the azimuth of the base line was 212.14°, and that the base line was left-handed. Then the zero of the scale opposite the left-hand end of the base-line arm would correspond to 212°, and the zero of the scale opposite the right-hand end would correspond to 32°. To orient the base-line arm to correspond with the actual base, it is necessary to swing the base-line arm clockwise through 0.14° ; that is, set the left end to 212.14°, The other would, of course, be set at 32.14°. 162 FIRE-CONTROL APPARATUS. Assume that the azimuth of the base line was 212.80°, then the left end would correspond to 213°, and the right end to 33°. To set the base line at 212.80° it would be necessary to swing the base-line arm counter-clockwise through 0.20°. In other words, the left-hand end is to be set at 212.80°, and the right-hand end at 32.80°. 783. To prevent error it is important that both verniers should be used, and both ends be set accurately. 784. The main azimuth circle and the gun azimuth circle of all boards issued are numbered at Frankford Arsenal in accordance with information furnished from the post at which the board is to be used. This information includes a state- ment of the azimuth of the normal to the base line, of the position of the secondary station with relation to the primary, and of the length of the base line. Bring the gun-arm center over the primary center by placing the zeros of the longitudinal adjusting slide verniers and the lateral adjusting slide vernier coincident with the zeros of their respective scales. Be sure that the zero of the worm guard is opposite 15 on the azimuth correction scale, and the scale on the micrometer head of the worm is at zero. Bring the primary arm to the normal line of the board. Be sure that the pointer of the index box on the primary arm is at zero. Place the targ against the reading edge of the primary arm, and bring the gun arm carefully against the targ. If done properly, the reading edges of the primary and gun arms will coincide with the normal line. Set the azimuth pointer at the gun-arm azimuth window, by means of the adjusting screw, to the whole degree of the azimuth of the normal line. Next, set the gun-arm azimuth subdial indicator to zero by loosening the screw holding the indicator in place. This will allow of an adjustment of one-fourth, one-half, or three- fourths of a degree. If this is not sufficient, the tally subdial is removed. The inner dial face can be adjusted now within the limits of one-fourth of 1 degree by loosening the retaining screw and moving the dial until the pointer is at zero. 785. To verify this setting, the gun arm should be mov^d away from the targ and brought up to it several times. The gun-arm center is moved to the position on the board corre- sponding to the position of the gun by moving the adjusting slides the required distances in the proper directions, depend- ing on the coordinates of the directing point, the primary station being taken as the origin. 786. Bach board is given a serial number, stamped on the name plate and right-hand end of the azmuth circle. 787. For suhealiber practice. — To provide for reading shorter ranges than are shown on the gun arm the graduations may be carried back to the inner end of the arm by the use of a paper scale pasted on the side of the arm, or the normal of the range correction scale of the gun arm and the ruler of the range board may be taken as 2,400, and a pa])er scale pasted on the gun arm showing ranges from 1,400 to 3,500 yards. FIRE-CONTEOL APPARATUS. 163 Plotting board for mortars. 788. The mortar plotting board is tJae same as above de- scribed, except tbat a mortar arm provided with a sliding scale graduated in degrees and minutes of elevation and times of flight for each zone, and a gun center with a larger azimuth circle, are substituted for the gun arm and gun center. The corrected elevation is read directly from the scale on the mortar arm. 789. The azimuth read from the mortar arm azimuth circle is corrected for drift, by means of the mortar deflection board. 790. For subcaliber practice at mortar batteries the scale of the plotting board may be increased to 150 yards to the inch where local conditions permit. I'nless subcaliber scales of 1.50 or 300 yards to the inch have been supplied, an eleva- tion scale for attachment to the mortar arm conforming to the scale at which the board is to be used should be con- structed at the post. Plotting ioard for fire commanders. 791. The plotting board for fire commanders is similar to the ordinary board, but has in addition a pantograph attach- ment and a reverse plot of the location of the batteries and stations. The gun center is mounted on ball-bearing lateral and longitudinal slides. It may be set over any desired point by means of the pantograph, the stylus attached to one of the arms of the pantograph being set over the corresponding point on the reverse plot. The important points on the reverse plot such as the directing points of the batteries, position finding stations, etc., are marked by small holes for the accu- rate setting of the stylus. POWDEB CHABT. 792. The powder chart is a chart to determine the velocity to be expected from a given charge of powder considered as a function of the temperature of the powder. It is constructed at the post and used in connection with a T-square, as shown in figure 7. The velocity scale is at the top of the chart. The T-square is graduated on the left edge for temperature. The velocity scale at the top of the chart is graduated 10 f. s. to the inch ; it reads from left to right. The normal velocity for the gun is placed in the center. In the figure this is taken as 2,250 f. s. A convenient length for the chart is 20 inches, which allows for a variation of 100 f. s. on each side of the normal. The left edge of the T-square is graduated in degrees Fahrenheit, beginning at — 10° at the bottom and ending at 100° at the top. A convenient scale is 10° to the inch, which requires a chart about 13 inches wide. 793. To construct the temperature-velocity curve. — Draw a horizontal line on the chart which will pass through the 70° mark on the T-squal-e, and consider this the axis X. Draw a line at right angles to this through the normal velocity and 164 FIEE-CONTEOL APPAEATTTS. consider it the axis Y. Then determine coordinates of points of the curve from the data contained in tables published from ■ \' -\ -om \ \ — \ -o!te \ -OK? \ •OK? 3 V (3] !5b o § s s s s Si 5 S! S 5 o -ewff \ CS^ y / / 5 \0 / <9 y) / o w ^ /V ses V \^ > -e«e <> \ -osee E .1, \o -OS/l % ^^^^■^ -^ -a/s -CV/f time to time in general orders from the War Department. (See General Orders, No. 23, War Department, 1909, p. 4.) R/iNOC BOAfore-sighting 526' dismissal of 312, 356 fire control Chapter VII general duties Chapter V general instructions 337—356 In commission 136, 832-834 In service 138,832 Inspection of 621-828 manning parties r 286 night drill 697,698 out of commission 832-834 out of service 832 service at the emplacement Chapter VI target practice, service G42-6S2, 689, 690 target practice, subcaliber 632-635 Battery commander 43, 277 access to power plants 608 appointment of rated enlisted men 292, 293 artillery inspection 621-628 assignment of officers 280, 282 auxiliary horizontal base system 498, 499, 517 commands of .355,356 correction of Are 675-678 duties at drill 308, 312, 314-316, 319-323, 354, 355, 350, 480^87, 498-504, 509-512, 677, 678, 697, 698 emergencies 320-323 emergency system 502-504 fire command target practice 642-658, 683-685, 688 horizontal base system 487-497 independent action 319, 543 indication and identification of a target 480-486, 509 indoor instruction 317, 984-987 inspection 318, 624, 625 minor defects 609 modifications in fire control and drill 316 night drill 697,698 records 314, 315 reports received 322 212 INDEX. [Numbers refer to paragraphs.] Battery commander — Continued. responsibility of 315, 609, 636, 655, 833 safety otBcer 684 subcaliber practice ; 631-641 vertical base system 500,501 Battery commander's action 319, 543, 545 Battery commander's observer 323 Battery commander's station 44,116,321,354 manning detail, gun battery primary armament 475—479 manning detail, mortar battery 505-508 Battery commander's walk 45 Battery parade 46 Battery practice, subcaliber 632-635 Battle area 47 Battle command 18, Chapter X communication olHcer 570 communications 725, 726 designation , 18 details 287, 289, 291, 317, 574 dismissal of 312 drill 569 fire-control system 575-579 indication of a target 576, 577 ; manning of 311 manning parties 575 manning tables 286 nigtit drill 697,699 rated men • 293 searchlight officer , 571—573 searchlights 572 service practice 042, 644, 647-658, 686-688 subcaliber practice 632, 635-638 typical 273 Battle commander, commands of 567, 578, 579 duties at drill 312,567,569,576-579 fire commander's action 579 inspection 621-628 nature of command 565 night drill 697, 699 reports from fire commanders 309 reports from mine commanders 310 responsibility of 566,567,654 searchlight commands 720,721 searchlights _ 572 714 service practice 642-644, 647-658, 686-688 Battle commander's station 116 instruction of detail for 317 manning party for 3IO 575 Bell, T I __ 251 497 Blast slope 4g Blending powder 49 ggs Block, breech. (See Breechblock.) ' Board, atmosphere. (See Atmosphere board.) deflection. (See Deflection board.) mortar deflection. (See Mortar deflection board.) plotting. (See Plotting board.) range. (See Range board.) time range. (See Time -range board.) Boat service 589 Book, emplacement IO7 Booth, information 520 Bore _ 50 Bore plug 78 Bore sighting 51, 526 Bore sighting, orientation and pointing Chapter "^^III Bourrelet 52 Breakdowns, of apparatus _ 007 of communications 323 INDEX. 213 [Numbers refer to paragraphs.] Breech _ 53 Breechblocks 54, 55 care of 872-876 aismounting of 082, 872 target practice 673, 679, 680, 682 Breech detail, 12-inch gun, D. C 389 Breech mechanism, care of 874-876 Breech recess 56 Breech reinforce 57 Buildings and grounds, police of 890,891,894 Bursting charge 58 C. Cable details 283 Cable, tests of 596,606 Call to arms 311 Cannon 61 Cannoneers, changes in position of 343 Canopy 62 Capital 63 Carbons, searchlight 724 Care of, ammunition service apparatus 835, 836 armament, post commander 599 batteries in commission 832-834 batteries in service 832 batteries out of commission 832—834 batteries out of service 832 .breechblocks 872-876 'breech mechanism 874-876 carriages 862-871 cartridge storage cases 883, 884 cylinders, recoil 849, 862, 869 detonators 918-922 drains and sumps 843 dynamite 924-934 electric installations and power plants 889 empty metallic cases and primers 882 Explosive "D" 936-946 explosives Chapter XIX fire-control stations 605-010 firing mechanism 874-876 fuses and primers 882,948-050 gas-check seat 680 gun cotton 932-968 guns 856-860, 888 hoists 835, 836 machinery, storage batteries, etc 611 material Chapter XVIII mortars 856-859, 861-868, 870-873 parapets 843 platforms 843 powder 885, 911, 912, 970-979 primers 882, 948-950 projectiles 877-881, 980-983 projectiles, filled and fused 980-983 property, ordnance sergeant 892, 894 recoil cylinders 849, 862, 869 searchlights 723 signal property 89.i smokeless powder 885, 970-979 stuffing boxes 870, 871 telautographs 741, 8S» telephones siq ial telescopes »i». »»' Caretaker detachments °*'"~°gS Carriages, A. E. F 67 barbette = 6' care of It casemate "' 214 INDEX. [Numbers refer to paragraphs.] Carriages, cleaning recoil cylinders 869 coast 67 definition 64-67 disappearing 67 fixed 65 L. F 67 masking mount 67 movable 66 packing stuffing boxes of 870,871 painting of 852 parts of, not expendable 846 rapid-fire guns 67 recoil cylinders 849,862,869 wheeled 66 Caliber of guns 59 Calibration 60 Cartridges for 3-incb gun 453-455 Case I 68,186,531 Case II 68,186,532 Case III 68,186,533 Casemate carriages 67 Casemate detail 283 Casemate electrician, definition 60 examination for 1004 Casemate, manning party for 563 Cases, empty metallic, care of 882 Cases for gun cotton 956-960 Cases of pointing 68,168,531-^533 Cases, Dowder, care of 882-884 Cease firing 653 Centering slope 50, 190 Chamber, powder 50, 190 Changes in fire-control system and drill 316, 543, 584 Changes in installation 316, 543, 584, 592 Changes in position of cannoneers 343 Charge, bursting 58 definition 70 powder, chuite for 191 priming 199 Charts, powder 792-795 Chase 71 Chief loader, definition 73 examination for 1004 Chief of ammunition service, definition-- 72 gun, 12-inch, disappearing carriage 403 mortar battery 373 Chief of detachment 285, 295,598 Chief of detail 285,298 Chief of section 285, 295, 298, 302, 307, 308 Chief planter, definltiou 74 examination 100-1 Chute, powder 191 Classification of searchlights 700 Cleaning bore and chamber 681 Cleaning material, allowance of 840 Cleaning recoil cylinders 889 Clinometer 75 Clinometer rest 7g "Close breech" gun, 12-inch, 1895 mechanism 384 gun, 12-inch, 1888 mechanism 332 gun, 12-inch, barbette carriage 430 mortar 37O Coast Artillery garrison 78 Coast Artillery reserves 78 79 Combination primers 352 Command, tactical (see also Mine command, fire command, bat- tle command) 245 Commands of battery commanders 355 353 battle commanders 5G7, 578' 579 fire commanders '545 INDEX. 215 [Numbers refer to paragraphs.] Commands, searchlight 720, 721 Commence firiug 673 Commercial detonators 017-922 Communication detail 283 Communication officer o46, 547 assignment of 275 battle command 570 Communications Chapter XVI battle command 725,726 breakdown of 323 defects in 606 failure of 498,502 maintenance of 602 means employed 725 out of commission 605 signal stations 727 telautograph service 741-748 telephone operators 728-740 telephone service 728-740 telephone tests 733,734 tests of 605, 600, 734 wireless 725 Companies, assignment of 278 Company commanders, appointment of rated men 292, 293 details by 289, 290 examination of rated men 997-1004 Company detail 283 Company, formation of 294-304 Company, gun 126,283,286 mine 162, 283, 284, 286 mortar 164, 283, 286 Computer 82 Construction of batteries 837 Continuance of qualification as gunner 1000 Control of searchlights 720 Corrected range 83 Corrections, abnormal 493 deflection 675-677 drift (see also Deflection board and mortar deflection board) 522 from observation of fire 675-678 how applied, battery secondary armament 525, 676 range 524, 525, 678 wind, gun battery secondary armament , 522 Correction scale, azimuth 761 range board 801 Corridor 84 Corridor wall 85 Counter recoil 215 Counter recoil springs, assembling or 867 cleaning and painting of 868 preservation of 864-866 removal of paint from 868 Counterweight 86 Counterweight well 86 Coyer post, mortar batteries 87,363-367 Crane 88 Crest, exterior 110 Crest, interior 139 Curves, range board— 802, 803 Cylinder, recoil, care of 84a, 8bz, Bba definition 216 D. Damage to, material 844 plotting room oOg Danger range gg Danger space -— »g Defects, in communications ?5S-5qq qaa In material 68A b»9, S44 216 INDEX. [Numbers refer to paragraphs.] Defense of coast line 1-3 Defense plans 123, 567-569 Defense zone, inner 271 Defense zone, outer 271 Definitions Cliapter II Deflection, definition 90 arbitrary corrections 675 liow set on sight 821 Deflection board 91, 757-768 azimuth correction scaie 761 deflection scale . 760 description of 757,758 leaf range scaie 764 multiplying scale 768 operation of 766-768 platen scale 758,759 subcaiiber board 765 T-square scaie 763 use of 675 wind arc 762 Deflection board for mortars (see Mortar deflection board) _ 780, 781, 789 Deflection corrections 675-677 Deflection errors, mortar batteries 512 Deflection scaie . 760 Delivery table 92 Density of loading . 93 Depression position finders 94, 189, 769-779 accuracy of 828 adjustment, Lewis D. P. F 774-779 adjustment, Swasey D. P. F 770-773 description of 769 D. P. F. system 180,500,501,517 Designation of, battle command 18 searchlights 718 Destruction of dynamite 934 Detachment 283 caretaljer 890-898 chief of 285 295 Details, battle command 287, 289, 291, 317' 574 casemate 283, 563 chief of 285,298 communication 283 company 283 company commander 289, 290 explosive 283 fire command 289, 291, 317 gun and mortar 283, 375, 391, 404, 405, 475-479, 503-508, 519, 520 mine command 288, 290, 291 600 powder 283, 375 projectile 283, 374 Detonators, commercial, care of 918-921 how supplied 917 inspection of 922 storage of • 918-921 Deviation, absolute 97 at the target 98 definition 95 mean lateral 9g mean longitudinal , 99 range 100 Device, obturating 55, 122, 170, 873 Devices, improvised 31g Diameter of bore 59 Differences, gun I27 range * 206, 528 Directing gun lOi Directing lights 71g Directing point lOi Disappearing carriage g7 INDEX. 217 [Numbers refer to paragraphs.] Dismissal of, batteries 312, 356 battle commanci 312 Dismounting breeclilocks 1 682 872 Displacement, definition Hi-' gun 1^,^ District artillery engineer, (i'ec Artillery engineer.) District, the artillery (see Artillery district Chapter XI, 19 how designated 20 District commander, appointment of rated enlisted men 292, 293 assignment of 580 assignment of companies by 278 assignment of officers by 274-277,279-282 attendance at target practice 587 caretaker detachments 890-898 command when absent from district 582 control of water transportation 586 duties at drill and durlnt; hostilities 584-590 duties during encampment 588 duties in general 584-590 inspections 585 modifications he may allow 584 modifications in proVisional installations 316 nature of command 583 night drill 590, 698, 699 rated enlisted men 1003 regulation of boat service 589 responsibility of 566, 584-590 service practice 643-658, 688 subcaliber practice 637 target practice 643-658,688 working parties 595 District, headquarters 580, 5S1 ordnance ofiicer. (See Ordnance officer.) Divisions of target practice 630, 632, 642 Double primary station, mine command, abbreviations and symbols 116 manning parties , 560 Double secondary station, mine tommanij, abbreviations and symbols 116 manning party 562 Drains and sumps 843 Drift 103 Drift corrections, gun battery, secondary armament 522 mortar (see also Mortar deflection board) 789 primary armament. (See Deflection board.) Drill, artillery, duties of artillery engineer 604 duties of battery commander 308, 312, 314-316, 319, 320-323, 354, 356, 480- 487, 49S-.-,04, 509-512, 077, 678, 697, 698 duties of battle commander 312, 567, 569, 576-579 duties of communication officer 546, 547 duties of district commander 584-590 duties of emplacement officer 307, 312, 324, 358, 372, 377 duties of fire commander 312, 543-545 duties of mine commander 312,545,556,564 duties of range officer 312, 323, 498, 500, 502 duties of searchlight officer 571-573, 710 formation for 294-300 gun, 12-lnch disappearing carriage 379-405 gun, 12-inch barbette carriage 428-434 gun, 10-ineh disappearing carriage 408^11 gun, 10-inch barbette carriage 436 gun, 8-inch disappearing carriage 414, 415 gun, .S-inch barbette carriage 439 gun, 6-inch disappearing carriage 417, 419-424 sun, 6-incb pedestal mount 442, 445 gun, 5-inch, 4.7-inch, 4-inch 447, 448 |uS; 3-inch - 4,50, 452-457 gun, 6-pounder 460-473 82615—09 15 218 INDEX. [Numbers refer to paragraphs.] modifications of 316,543,584 Drill, mortar, 12-incli 381-375 night 500, 696-099 primers 346 record of attendance 314 service at emplacement Chapter VI Dry gun cotton 964-968 Dummy ammunition 341,394 Dynamite 923-934 decomposition of nitroglycerine in 933 destruction of 934 exposure to air 926 gloves for handling 928 inspections of 931-934 marking of packages 930 packing 923 principal source of danger 932 storage and care of 924-934 storage cases 927 temperature of freezing 025 E. Bight-inch gun battery. (See Gun battery, 8-inch.) Electrical installation, care of 889 Electrician, casemate. (See Casemate electrician.) Electrician sergeant, care of property 893 care of telautographs 741 duties 611, 613 supervision of 613 lllectric motors for gun carriages 308 Elements of trajectory 254 Elevation, definition 104 quadrant 104, 201 setter 105, 361, 363 sight 104, 239 Eligibility for rated positions 999 Eligible list for rated positions 998-1001 Emergency 320, 323 Emergency practice, subcaliber 632, 634 Emergency station, abbreviation and symbols 116 manning party 478, 508 Emergency system, definition 189 gun battery, primary armament 502-504 indication and identification of targets 480 mortar battery 517 Emplacement, definition 106 inspection of 622,625,628 ■ range keeper 479 service at Chapter VI Emplacement book 107 Emplacement officer, general duties 324 general duties at drill 307,312,324,358,372,377 gun battery, 12-inch D. C 376, 377 gun battery, 12-inch barbette carriage 425-428 gun battery, 10-inch D. C 406 gun battery, 10-inch barbette carriage 435 gun battery, 8-inch D. C 412 gun b.attery, 8-inch barbette carriage 438 gun battery, 6-inch D. C 418 gun battery, 6-inch pedestal 442, 443 gun battery, 3-inch 4.">0, 451 mortar battery 357,358,372 Empty metallic cases, care of 882 Encampment, duties of district commander 588 Energy of projectiles 108 Engineer, artillery. (Sre Artillery engineer.) Engineer Department S:',7, 838 Engineers 611, 614 Engineer property, minor defects 609 repairs of 593, 594, 002. 603 INDEX. 219 [Numbers refer to paragraphs.] Enlisted personnel :;83 Equalizing pipe 1U9 Errors, deflection, mortar batteries 512 Examination for rated positions ;i'.)7-100-t Examination for gunners (see oiso Gunners' instruction). Chapter XX Exbibiting data for R. F. batteries 320, 521 Expendability of parts of armament S46 Explosives Chapter XIX Explosive " D " 035-946 barrels for 93T-941, 945, 946 inspections 943-946 marking of barrels 937-941 packing of 0:i.j storage and care of 936-'.)42 Explosive detail 283 Explosives, black powder 911, 912 care of Chapter XIX commercial detonators 917-922 dynamite 923-934 explosive "D" 935-946 fuses and primers 198, 346-350, 352, 650-651, «S2, 947-050, 965 general instructions 899—916 gun cotton 951-968 inspection 899 projectiles filled and fused 980-983 shipment of 886 storage cases for 900-905 Exterior crest 110 Exterior slope 111 r. Faces of trunnions 263 Failure of apparatus 607 Failure of communications 498, 502 Field artillery 61 Field officers, assignment of 274 Field of Are, definition 112 safety of 636,654 Field works 3 Fire, observation of 675-678 orders of 172, 544, 545 restricted 172, 220, 545, 578 unrestricted 172, 267, 545, 578 Fire and mine commands Chapter IX Fire area 113 X'^ire command practice. [See Target practice.) Fire command, definition and organization 15, 16 designation of 18 details 289, 291, 317 dismissal of 312 fire-control system 551-555 general 541-550 grouping of batteries 16 indication of a target 553-555 manning parties 286, 287, 289, 291, 548-552 manning table 2si; night drill 697,699 rated men 203 stations 116, 551, 552 target practice (service) 642-658,68.3-685,688 tarlet practice (subcaliber) 632,633,63.5-637 Fire commander, action 579 assignment of -74, 270, 281, 645, 646 commands of 54.5 communication officer 546 duties of 541-546, 683 gunners' instruction, supervision of O.'^l independent action 543 instruction, manning parties 31/ 220 INDEX. [Numbers refer to paragraphs.] Fire commander, manning party 286, 287, 289, 291, 548-552 manning tables 286 modifications of regulations 543 nature of command 542 night drill 543,697,699 orders of fire 545 plotting board 791 records 543 reports to battle commander 309 responsibility of 541. 543, 654 rated men 293,997,1004 searchlight 711, 712 supervision of target practice 281, 543 target practice (service) 642-658,683-685,688 target practice (subcaliber) 632, 633, 635-637 Fire-control, the battery Chapter VII apparatus Chapter XVII definition 114 installation 114, 474 material 115 manning details for gun batteries, primary armament 475—479 manning details for gun batteries, secondary armament 519 manning details for mine stations 288, 290, 291 manning details for mortar batteries 505-508 manning details for other stations 600 methods for subcaliber practice 638 modifications 316, 543 personnel 115 range officer 209, 312, 325, 498, 500, 502 responsibility for apparatus 599-620 sections 283, 333 Fire-control station, abbreviations and symbols (see also Sta- tion) 116 care of 605,610 construction and maintenance of 837 inspection of 623, 628 Fire-control system, battle command 576-579 definition 114 fire command 551-555 gun battery of the intermediate armament 518 gun battery of the primary armament 474-504 gun battery of the secondary armament 519-525 mine command 559-564 modifications of 316,543,584 mortar battery 505-517 Firemen 611, 615 Firing attachment, 12-inch gun, D. C 887 Firinp- by electricity 651 Firing interval, definition 117 gun, 12-inch 401 mortar battery 514,516 Firing mechanism 55, 352 874-876 First-class gunners, examination of 984-996 instruction of 317, 984-996, 1000, 1003 First sergeant, formation for artillery drill 295-299 formation for infantry maneuvers 303 formation for roll calls 301 302 Five-inch gun battery. (See Gun battery, 5-inch.) Fixed ammunition _ 70 Fixed lights 116, 118, 700, 707,"'715, 717 Fixed targets for trial shots 668 Flags, at target practice 649 for signaling 725 Floating defenses ~ o Focusing telescope ^^q Forcing cone 50,119 Formation, for artillery drill "94-304 for infantry maneuvers ~ 303 for roll calls.. 301,302 INDEX. 221 [Numbers refer to paragraphs.] Formation, for marching maneuvers 304 of company 294-304 of sections 295, 296 Fort, artillery 77 Fortification power plants, load on 592 Fortifications 3, 4, 837 Four-inch gun battery. (See Gun battery, 4-inch.) Four-and-seven-teuths-inch gun battery. (See Gun battery, 4.7-inch.) From battery 120 Fuses and primers 047-950 G. Gallery, definition 121 shot 235 Garlock packing 862 Garrison, coast artillery 78 Gas check 122 Gas-check seat, care of 680 General defense plans 1l'3, 567-569 General instructions — the battery 337-356 General principles Chapter I Grooves 124,221 Grouping of batteries in fire commands 16 Gun-arm center 784, 785 Gun battery, intermediate armament 5, 8, 10 fire-control system 518 Gun battery, primary armament, flre-control system 474-504 Gun battery, secondary armament, fire-control system 519-525 corrections 523, 676 Gun battery, 12-inch D. C, adjustment of indices 527 ammunition service 403-405 auxiliary horizontal base system 498, 499 bore sighting 526 breech detail 389 chief of ammunition service 403 close breech 382, 384 drill 379^05 emergency system 502—504 emplacement officer 376, 377 failure to go in battery 395 fire-control system 474-504 firing attachment 387 gun section 376 horizontal base system 487—497 indication and identification of targets 133, 137, 480^86 inspection after firing 682 load and fire 379, 385, 386, 391 manning details, fire control 475-479 method of pointing 532 notes on the drill 380-405 open breech 381, 383 organization of 376 pointing test 534-537 powder detail 405 projectile detail 404 rammer and truck detail 391 range differences 528 range setter 393, 400 retracting gun 402 shot trucks 392 time to load 401 tripping gun 390 vertical base system 500, 501 Gun battery, 12-inch, barbette carriage, adjustment of indices 527 ammunition service 434 auxiliary horizontal base system 498, 499 bore sighting 526 close breech 430 222 INDEX. [Numbers refer to paragraphs.] Gun battery, 12-incli, barbette carriage, drill 428—434 emergency system 502-504 emplacement olficer 425-428 fire-control system 474-504 gun section 426 horizontal base system 487-497 indication and identification of targets 133, 137, 480-486 inspection after firing 682 lanyard 432 load and fire 431^33 manning details, fire control 475-479 method of pointing 532 notes on the drill 430-434 open breech 430 organization of 425-427 pointing test 534-537 ramming projectile 433 vertical base system 500, 501 Gun battery, 10-inch, D. C, adjustment of indices 527 ammunition service 409 auxiliary horizontal base system 408, 499 bore sighting 526 drill 408-411 emplacement officer 406 emergency system 502-504 failure to go in battery L 395 fire-control system 474—504 gun section j. 407 horizontal base system 487—497 indication and identification of targets 133, 137, 480-486 inspection after firing 682 manning details fire control 475—479 method of pointing 532 notes on the drill 409-411 organization of 406, 407 pointing test 534-537 rammer and trucli detail 391 range differences 528 shot trucks 392 tripping gun 390 vertical base system 500, 501 Gun battery, 10-inch, barbette carriage, adjustment of indices 527 ammunition service 437 auxiliary horizontal base system 498, 499 bore sighting 526 drill 436, 437 emergency system 502-504 emplacement oflicer 435 fire-control system 502-304 gun section 436 horizontal base system 487—497 indication and identification of targets 133, 137, 480-486 inspection after firing 682 manning details, fire control 47.5-479 method of pointing 532 notes on the drill 43^ organization 435-437 pointing test 534-537 vertical base system 500,501 Gun battery, 8-iuch, D. C, adjustment of indices 527 ammunition service 414 auxiliary horizontal base system 498, 409 bore sighting 5'>6 drill 414, 415 emplacement oflicer 412 emergency system 502-504 failure to go in battery 395 fire-control system 474-504 gun section 413 INDEX. 223 [Numbers refer to paragraphs.] Gun battery, 8-inch, D. C, horizontal base system 487-497 Indication and identification of targets 133, 137, 480-486 inspection after firing 682 manning details, Are control 475-479 method of pointing 532 notes on the drill 415 organization 412, 413 pointing test 534-537 rammer and truck detail 391 range differences 528 shot trucks 392 tripping gun 390 vertical base system 500, 501 Gun battery, 8-inch, barbette carriage, adjustment of indices 527 ammunition service 440 auxiliary horizontal base system 498, 499 bore sighting 526 drill 439, 440 emplacement officer 438 emergency system 502-504 fire-control system 474-504 gun section 439 horizontal base system 487-497 indication and identification of targets 133, 137, 480-486 inspection after firing 682 manning details, fire control 475^79 method of pointing 532 notes on the drill 439-440 organization 438,440 pointing test 534-537 vertical base system 500, 501 Gun battery, 6-incb, D. C, adjustment of indices 527 ammunition service 422,424 auxiliary horizontal base system 498, 499 bore sighting 526 drill 417, 419-424 emplacement ofllcer 418 emergency system 502-504 gun section 418 fire-control system 474—504, 518 horizontal base system 487-497 indication and identification of targets 133, 137, 480-486 inspection after firing 682 load and fire 420 manning details, fire control 475—479 method of pointing 532 notes on drill 420,424 organization of 416, 418 pointing test 534-537 range differences 528 retracting gun — 421 time to load 423 vertical base system 500, 501 Gun battery, 6-incb, pedestal mount, ammunition service 444 auxiliary horizontal base system 408, 499, 523 bore sighting 526 drill *f2, 44o emplacement oflcer iii'SnA emergency system 502-504 fire-control system 475-479, 518 gun section 443 horizontal base system t:;-7^; f SI~tSX indication and identification of targets 133, 13 r, 480-486 Inspection after firing 682 method of pointing M^ notes on the drill ttt-t,., fi-r organization of 441, 443, 444 pointing test g*0 vertical base system sou, 5Ui 224 INDEX. [Numbers refer to paragraphs.] Gun battery, 5-incIi, 4.7-inch, 4-inch, ammunition service 447. 448 1 smolteless powder 900 racking boxes, for projectiles 879 Packing, Garlock 802 I'acking stuffing boxes 871 Pad. adjustment of S73 232 INDEX. [Numbers refer to paragraphs.] Painting 850-855 barrels for Explosive " D " 946 carriages 852 guns and mortars 851 marking guns, mortars, and pits 855 name plates 852 projectiles 880 Paints 838-840, 842 allowance of 850 preparation of 850, 853 removal from counter recoil springs 868 removal from guns and carriages 854 Pamphlets, Ordnance Department 847 Parade, battery 46 Parade slope 176 Parapet, care of ; 843 definition 177 Paulins 888 I*ermanent fortifications 3, 4 Permanent installations, modifications of 316 Personnel, artillery district headquarters 581 fire control 115 Piling projectiles 878 rincb bars 395 Pipe, equalizing 109 Pit 178 Pit commander 125, 170, 334, 359 at inspections 626 Pit, mortar, marking of 855 Pit section 283 Plane of departure 180 Plane of direction 181 Plane of sight 182 Plan, general defense 123, 567—569 Planting and loading sections, divisions of 283 Planting detachments 283 Platen 758 Platen scale 758, 759 Platform, care of 843 gun 129 loading 152 truck 261 Plotter, auxiliary horizontal base system 499 definition 183 examination for 1004 horizontal base system 480 indication and identification of a target 481 mortar battery 511^ 513 responsibility of 3,S2 vertical base system 500 Plotting board, adjustment 782—785 definition lg4 description of 782 detachment 283 detail - •jo'j mortars 788-790 numbering 78q orientation 782-785 subcaliber 7^1, 790 subcaliber, mortar " ' 790 Plotting room, damage to 503 definition lyg gun battery, primary armament, manning detail 47(5 mortar battery, manning detail 506 Point, directing 1 jqj I'ointing 21, 68, 186. 531-533 method of _ 21,68,186,531-533 INDEX. 233 [Numbers refer to paragraphs.] Pointing test, gun battery primary armament 534-537 mortar battery 538 rapid-flre batteries 540 records of 536,330 Point of fall 187 Point of impact 188 Police, buildings and grounds 890, 891, 894 Position finder. (See Depression position finder.) Position finding system 189 Position of guns, habitual 860 Position of mortars, habitual 368, 861 Post artillery engineer. {See Artillery engineer.) Post commander 281, 598-601 care of armament 599 details made by 287, 599-601 efficiency of personnel 599 manning tables 286 nature of command 598, 599 responsibility of 556, 599 Post headquarters, detail of manning parties 287 Posting sections 307, 308, 359 Post manning tables 286 Post ordnance ofBcer. (Sec Ordnance officer.) Posts, cover 87, 363-367 Posts, mortar battery, at inspection 362, 367 Post telephone switchboard 116 Post, the Chapter XII Powder, blending 49,885 care of 885,911,912,970-979 delivery of for target practice 656, 673, 674 inspection of 973-979 -lots to be used 663,664 package, smokeless 969 poor practice due to 665 report of 665 sample bottles 975-978 samples of 974 service of 365,396,656,673,674 shipment of 886 storage and care of 885,970-979 storage cases 972 storage of 661, 662, 885 target practice 661-665, 673, 885 temperature of magazines 662, 910, 971 test, litmus 975-978 Powder chamber 50, 190 Powder charges, delivery at target practice ' 656, 673, 674 handling, 12-lnch battery 396 weights of 796 Powder charts, construction of 793 description of 792,793 examples of use 795 object of 792 use of 794, 795 Powder chute 191 Powder detail 283 12-inch gun, D. C 405 mortar battery 375 Powder hoist 192 Powder hoist well 193 Power detachment 283 Power plants, access to 608 batteries 608 care of 605 construction and maintenance of 837 duties of engineers 614 duties of firemen 613 duties of master electricians 612 Increase of load 592 82615—09 16 234 INDEX. [Numbers refer to paragraphs.] Power plants, inspections of 62S repairs to 592-594 Power sections, organization of 283 Practice. (See Target practice.) > Precautions for safety, l5attery practice 647-658 battle command practice 687 Are command practice 684, 685 primers 352 salutes 693-695 Predicted point 194-196,371 Predicted time 195 Predictor 196 Predicting and firing, mortar batteries 511—516 Predicting Interval 194 Preliminary practice, subcaliber 632,633 Preparation of paints 850, 853 Preparations for inspection 621 Preparations for target practice 658, 667, 885 Pressure gauges 671, 672 Primary armament (see also Gun battery, primary armament). 6, 10 Primary stations, abbreviation and definition 39, 116, 197 fire command manning party 551 mine command manning party 559 Primers, care of 882,948,949 combination 352 definition 198 drill 346 guncotton 965 insertion of ^ 347 inspection of 950 obturating 350 package 947 precaution in case of failure 350 service 347-349 target practice 650,651 Priming charges 199 Probable muzzle velocity 814,815 Projectile detail, gun, 12-inch, D. C 283, 404 mortar battery 374 Pro.iectiles, care of 877-881, 080-982 delivery of, for target practice 673, ri74 dummy 394 energy of 108 filled and fused 980-983 inspection of 983 loading of 881 paclfing boxes for 879 painting of 880 piling of 878 preparation for target practice 666 removal from gun 653 storage of 080-982 target practice 653,666,673,877 travel of 255 Property officer, mine command 558 Property returns 846 Provisional installation modifications 316 Q- Quadrant, adjustment of 530 definition 200 Quadrant elevation 104, 201 Qualification, as gunner, continuance of 1000 of rated enlisted men (see Rated enlisted men) 907-1004 Quartermaster Department, supplies 842 INDEX. 235 [Numbers refer to paragraphs.] R. Raiding parties 3 Rammer detail, gun battery, 12-incli 391 Ramming projectiles, gun, 12-inch, barbette carriage 433 Ramp 202 Range, corrected 83 corrections 525, 678 danger 89 definition 203 deviations 100 differences 206, 528 searchlight 229 Range azimuth table 204 Range board, adjustment of, boards issued December 20, 1906, and subsequently 813 boards issued prior to Deeemebr 26, 1906 812 corrections 678 correction scale 801 curves 802, 803 definition 205 general description 798—807 mariners ' 805 nomenclature 797 operation 808-815 probable muzzle velocity from 814, 815 reference numbers 804 ruler 800 travel ruler 806, 807 Range corrections, target practice 678 Range finder (see Depression position finder j 94 definition 207 Range-finding station, manning details, secondary armament (see also Fire-control station) 519, 520 Range-finding system, battery of secondary armament 520-525 Range keeper 208 Range officer 209 duties at drill 312, 325, 498. 000, 502 inspection 623 Range scale, calibration 60 Range setter, definition 210 gun battery, 12-inch 393, 400 Rapid-fire batteries, manning details 519, 520 mine command 17 pointing tests 540 range-finding system ri20-.")2.5 Rapid-fire gun 211 Rapid-fire gun carriage 67 Rated enlisted men, appointment of 292, 293, 1003 battle command 293 continuance of qualification as gunner 1000 eligible for examination 909 eligible list !i98-1001 examinations of 997-lUii4 medical examination 1002 qualification of 997-1004 scope of examination 1004 Rated positions, scope of examination 1004 Reader 331 Ready 212, 358 Rear slope . 213 Receiving table 214 Recess, ammunition 23 breech 56 truck 262 Recoil 213 Recoil cylinders, care of S49, S02 cleaning 809 definition 216 236 INDEX. [Numbers refer to paragraphs.] Record, attendance at artillery drill 314 pointing tests 536,539 Record practice, emergency conditions (subcaliber) (see also Target practice, subcaliber) 632 normal conditions (subcaliber) 632 Records, artillery engineer 607 of fire commander, target practice 683 Reference numbers 90, 217, 804 Regulations, for target practice, modifications in 688 of boat service 589 Relay 218 Relocation 155 Removal of paint from counter recoil springs 868 Removal of primers 650 Repairs, engineer property 593, 594, 602 minor defects 609 to power plants 592-594 Reports, artillery engineer 607 defects in material 6s;;, 689, 844 during drill, practice or action > 322 powder 665 target practice : 082, 6S9, 690 Requisitions by ordnance officer : 597 Reserve ammunition 315 Reserve detail 283 Reserves, coast artillery 78,79 Reserve table 219 Responsibility, artillery engineer 605, 609, 610 battery commander 315,609,636,655,833 battle commander 566,567,654 district commander 566, 584-590 field o( Are 636, 654, 657 fire commander 541,543,654 gun commander 845 "mine commander 556, 557 ordnance officer 597, 833 post commander 556,599 tactical, definition 246 Restricted fire 172, 220, 545, 578 Retraction of gun 402, 421 ropes 402 Rifling 221,266 Rimbase 222 Roll calls 297 formation for 301, 302 Round 223 Roving light 224, 700, 707-710, 715, 717 Ruler, range board 800 Rules for using telautograihs 748 telephones ■ 1 739, 740 S. Safety, field of fire 636,654 Safety oflicer (J84 Salutes 691-695 precautions (or safety 693-095 Saluting interval 692 Salvo 225 Salvo point 226, 545 Salvo table 227 Sample bottles, powder 975-978 Samples of powder 974 Scope of examination, for gunners 994-996 for rated positions 1004 Searching with lights 710-714 Searchlight, battle command 572, 714 care of 72,'^ carbons for 724 classification of _ 70Q INDEX. 237 [Numbers refer to paragraphs.] Searchlight, commands 720, 721 control of 720 definition, lis. 134, 224 designation 718 directing 716 fixed 110, 118, 700, 707, 715, 717 illuminating i:!4, 700, 711, 712, 714 indication of a target 577 maintenance of 602 manning parties for 70.3-706 mine 572, 713, 714 normal use of 717 roving 224, 700, 707-710, 715, 717 searching 710-712 sectors 709 service of the lights 700-724 standard 701 telephone operators for 702, 706 two lights working together 716 vessels, thrown on 719 watcher 706, 710 Searchlight area 228 Searchlight officer 274, 571-57S, 702, 710, 720 duties at drill 571-573, 710 Searchlight operator 702-710, 721-724 Searchlight, range 229 Searchlight station, abbreviation 116 maintenance 610 manning parties 703-706 Secondary armament (see also Gun battery, secondary arma- ment) 5, 0, 10 abbreviation 116 Secondary station, abbreviation 116 battery manning party 475-479, 505-508, 519 definition 39, 230 fire command manning party 552 mine command manning party 561, 562 Second-class gunners. (See Gunner.) Section, ammunition 283 Sections, chief of 285, 295-298, 302, 307, 308 formations of 295, 296 gun 376, 407, 413, 418, 426, 436, 439, 443, 448, 451, 450 posting 307, 308, 359 Sector, searchlight 709 Selection of observers .■;26, 327 of telephone operators 728-732 Semi-automatic guns 156 Service at the emplacement Chapter VI Service of ammunition, gun battery, 12-inch, disappearing car- riage 403-405 gun battery, 12-inch, barbette carriage 434 gun battery, 10-inch, disappearing carriage 409 gun battery, 10-inch, barbette carriage 437 gun battery, 8-inch, disappearing carriage 414 gun battery, 8-lnch, barbette carriage 440 gun battery, 6-inch, disappearing carriage 424 gun battery, 6-inch, pedestal mount 444 gun battery, 5-inch, 4.7-inch, 4-inch 447, 448 gun battery, 3-inch 453-4.^5, 457 gun battery, 6-pouuder 463-467, 472 mortar battery 373-375 Service of the piece, general instructions 337-353 gun battery, 12-inch, disappearing carriage 376-405 gun battery, 12-lnch, barbette carriage 425^34 gun battery, 10-inch, disappearing carriage 406-411 gun battery, 10-inch, barbette carriage 435-437 gun battery, 8-inch, disappearing carriage 412-415 gun battery, 8-inch, barbette carriage 438-440 gun battery, 6-inch, disappearing carriage 416-424 gun battery, 6-inch pedestal mount 441-445 238 INDEX. [Numbers refer to paragraphs.] Service of the piece, gun battery, 5-inch, 4.7-inch, 4-inch 446—448 gun battery, 3-inch 449-45T gun battery, 6-pounder 458-473 mortar battery 357-375 Service of powder 365, 396, 656, 673, 674 Service of searchlights 700-724 Service of telautographs 741—748 Service of telephones 728-740 Service practice. (See Target practice.) , Service primers 347-349 Serving table, definition 231 for 6-pounder-battery 472 Set forward point 196, 232 Shell, use of. 6 Shell room 233 Shell tracers 234 Shipment of explosives 886 Shot, use of 6 Shot gallery 235 Shot hoists - 236 Shot hoist well 237 Shot truclis 392 Shots, trial. (See Trial shots.) Side arms, at drill 300 Siege artillery 61 Sight elevation 104, 239 Sights, definition 238 open 238 telescopic 238, 249, 821 Signaling, visual 602, 649, 725 Signal property, care of 893 Signals, at target practice 649 for service of piece 353 Signal station 116, 610, 727 supplies 841 Six-inch gun battery, disappearing carriage. {See Gun battery, 6-inch, disappearing carriage.) Six-inch gun battery, pedestal mount. (See Gun battery, 6-inch, pedestal mount.) Six-pounder battery. (See Gun battery, 6-pounder.) Slope 25 Slope, blast . 48 Slope, centering 50, 190 Slope, exterior 111 Slope, interior 140 Slope, parade 176 Slope, rear 213 Slope, superior 242 Smolteless powder (see Powder) 969-979 Speaking tube 725 Sponging, salutes 694 target practice 652 Springs, assembling of 867 cleaning and painting of 869 counter-recoil, preservation of 864-866 removal of paint from 868 Staff officers, assignment of _ 274 Stand fast 345 Standard searchlight 701 Starting motor 835 Station, base-end 30 hq battery commander 44, 116, 321, 354^ 605 double primary H6, 560 double secondary 116 552 fire-control, abbreviations 116 fire-control, care of _ 610 Inspection of ~ ~623, 628 meteorological 116, 610, 617-619 observing 116, I69 primary 39, hq 197 INDEX. 239 [Numbers refer to paragraphs.] Station, range finding. (Sec Fire-control station.) searclilight 116, 010 secondary 39, 116, 230 signal 116, 610, 727 supplementary 39,116,243 tactical command : 272 tide 116. 610, 620 wireless 116.610 Storage and care of dynamite 924-934 Storage and care of explosive "D" 936-942 Storage and care of fuses and primers 948, 94P Storage and care of gun cotton 952-960.966 Storage and care of smokeless powder 970-977 Storage batteries, care of 611 Storage cases, cartridge 883.884 for explosives ... 900-905 for smokeless powder 972 Storage of black powder 911. 912 Storage of detonators 918, 919 Storage of dry gun cotton . 966 Storage of explosives Chapter XIX Storage of powder___^ 661, 602, 885 Storage of projectiles 980-982 Striking angle 240 Striking velocity 241 StuiHng boxes, removal of packing from 870 repacking of 871 Subcaliber ammunition. (See Ammunition.) Subcaliber deflection board . 765 Subcaliber gun, adjustment of 633 Subcaliber practice. (See Target practice, subcaliber.) Subcaliber practice plotting board 787 Subcaliber practice plotting board, mortar 788, 790 Subdivisions, remote stations, dismissal of 313 Submarine defenses 4 Submarine mines 161. Superior slope 242 Supervision of electrician sergeants 613 Supervision of target practice 2.H1, 543 Supplementary stations 39, 116, 243 Supplies, Engineer Department 838 Ordnance Department s:!9. S40 quartermaster 842 signal 841 Supports, coast artillery 3, 19. 78, 80 Swasey, D. P. F., adjustment of 770-773 Swell of the muzzle 244 Switchboard, post telephone 116 Symbols and abbreviations, fire-control stations 116 T. Table, delivery 92 Table, manning 159, 286 Table, orientation 174 Table, range, azimuth 204 Table, receiving 214 Table, reserve 219 Table, salvo 227 Table, serving 231 Tactical chain, units of 12 Tactical command 245 Tactical command, stations for 272 Tactical responsibility 246 Take cover 344 Targ 247 Target, definition 248 for trial shots 668 Identification of 133, 480^86, 509, 521, 523, 553-555 240 INDEX. [Numbers refer to paragraphs.] Target, indication of_-_ 137, 480^86, 509, 521, 523, 55.3-555, 576, 577 location of 155 relocation of 155 travel of 256 Target practice Chapter XIV Target pi-actice (service), ammunition service 674 arbitrary deflection correction 675 attendance at 587 battery commander, safety ofiicer 684 battery 642-682, 689, 690 battle command 642, 644, 647-858, 686, 687-, 688 breechblocks 673, 679, 680, 682 cease firing 653 cleaning of bore and chamber 681 commence firing 673 delivery of powder charges 6.')6, 673,674 district commander 643, 658, 688 divisions of 630, 642 Are command 642-650,683-685 firing by electricity 651 flags and signals 649 gas check ■ 680 gun pointer 675 inspection after firing 682 mine commander 281 misfires 650, 651 modification of practice regulations 688 observation of fire 675-678 orders relating to 629, 658 powder 661-665, 673, 885 precautions for safety 647-658, 684, 685, 687 preparations for 658-667, 885 pressure gauges 671, 672 projectiles for 653, 666, 673, 877 range corrections 678 records of fire commander 683 removal of primers 650 removal of projectiles 653 reports 682, 689, 690 responsibility for field of fire 636, 654, 657 sponging 652 supervision of 281, 543 time of 643 trial shots 667-672, 814, 813 Target practice (subcaliber), at home stations 641 battery 632-635 battle command 632, 635, 638 deflection 765 deflection board 765 determination of muzzle velocity 633 district commander 637 divisions of 632 emergency 632, 634 gun pointer 039 methods of fire control 638 normal condition 632 object of 631 preliminary 032, 633 record 632 responsibility, field of fire 036 time of 637 vi-here held 640 Telautograph, care of 741, 889 service ofj 741-748 Telephone operators, selection of 728—732 test of 729, 730 training of 7.35 Telephone operators for searchlights 702. 706 INDEX. 241 [Numbers refer to paragraphs.] Telephones, care of 735-738 test of 733, 734 Telephone service 728-740 Telephone switchboard 116 Telescope 819, 820 adjustment of 820 care of 819, 887 focusing of 820 repair of 887 Telescopic sight 238, 249, 821 Temperature of magazine 662, 910, 971 Ten-inch gun battery. (See Gun battery, 10-inch.) Test, ammunition service 628 cable 596, 606 communications and mine cables 596, 605, 606, 734 litmus paper 975, 978 new devices and methods 316, 543 observers 330 telephone operators 729, 730 telephones 733, 734 Thermometers 617, 822 Three-inch gun battery. (See Gun battery, 3-inch.) Throttling bar 250 Tide observer 620 Tide station 116,610,620 Time interval bell 251, 497 Time interval system 497, 823 Time of target practice 637,643 Time range board 252, 393 Time to load, gun battery, 12-inch, disappearing carriage 401 gun battery, 6-inch, disappearing carriage 423 Tracer, shell 234 Tracking 253 Training of telephone operators 735 Trajectory , 254 Travel of projectile 255 Travel of target 256 Travel ruler SOO, 807 Traverse 257 Traversing by electricity 399, 400 Traversing indicator 258 Trial shots, metorological observations 670 object of 259, 525, 669 pressure gauges 671 probable muzzle velocity 667-672, 814, 815 targets for 668 Training and examination of candidates for gunners and spe- cial ratings Chapter XX Tripping 390, 395 Trolley 260 Truck, detail, gun b.ittery 391 platform 261 recess 262 shot 392 without brakes 397 Trunnion band 264 Trunnions 263 T-square scale 763 Tube 265 Tug 586 Twelve-inch gun battery. (See Gun battery, 12-inch.) Twist of rifling 266 Typical battle command 273 TJ. Units of tactical chain 12 Unrestricted Are 172, 267, 545, 578 242 INDEX. [Numbers refer to paragraphs.] V. Vane, wind 829- Velocity, muzzle. (See Muzzle velocity.) striking 241 wind 617, 618- Vent 268, 681 Vertical base system, gun battery, primary armanent 500,501 indication and identification of a target by 482 mortar battery 51T Visual signaling 602, 649, 725 W. Walk, battery commander's 45 Wall, corridor 85 Wall, interior 141 War Department, authority for modifications in permanent installation 31& Washing bores 681,682 Watchers, searchlight 706, 710 Water front 269 Water tran&poi-tation 586 Weights of powder charges 796 Well, counterweight 86- powder hoist 193 shot hoist 237 Wheeled carriage 67 Wind, azimuth and velocity of 617,618 Wind arc, the 762 Wind component indicator, definition 270- object and description of 824-827 operation of 828 Wind corrections, gun battery, secondary armament 522^ Wind vane 829 Wireless communication r 725 Wireless stations 116, 610 Working parties 595- Z. Zone 271 o