GINS: Field and siege, 146; garrison, 146; casemate, 146. GOMER CHAMBER, 32. GRAPE SHOT, 91; weight of, 107. GRATES for heating shot, 98. GRAVITY: Specific, 159 —Force of, 159. GREASE for wheels, 158. GROOVES for rifle cannon, 163-4. GRENADES: 91 —Angle of elevation for, when thrown from stone-mortars, 67. GROMMETS, 99. GUNS: Definition, 26 —Lengths, 27 —Weights, 27 —Proof, 22 —Ranges, 68-9, 70-1-2 —Nomenclature, 13, 14, 15 —Principal parts of, 26 —Projectiles used with, 27 —How mounted, 26 —Natural angle of sight of, 26. GUN METAL: Bronze, 9, 10 —cast-iron, 9, 10. GUNNERS’ IMPLEMENTS: Level, 18 —Quadrant, 18 —How used, 52-3. GUN-CARRIAGES: Field, 125-6; siege, 128; barbette, 132-4; casemate, 138-9; flank-casemate, 140; mountain howitzer, 127; wrought iron, 141; prairie, 127-8 —Columbiad, 136-7. GUNPOWDER: Materials, 83 —Proportions, 83 —Manufacture, 84 —Qualities of, 87 —Packing, 87-8 —Proving, 86 —Expansive velocity and pressure, 87 —Hygrometric proof, 87 —Relative quickness, 87 —Preservation and storage, 88-9 —Transportation, 89. HAND-CART, 145. HAND SLING-CART, 145-6. HAUSSE: Pendulum, 17. HAY: Weight of, 154. HORSES: Number required for a field battery, 42; for siege train, 37 —Power of, 152 —Space occupied by, 152 —Number required for siege-gun, 129 —Weight, 152. HORSE-ARTILLERY: Peculiar advantages of, 43. HOT SHOT, 97-8 —Loading with, 97 —Expansion of, 96. HOWITZERS: Definition, 28 —Kinds of, and weights, 29; —Lengths, 28-9 —Number in field battery, 41; in siege train, 36 —Chamber, form of, 28 —Advantages of, 28 —Projectiles used with, 28 —Natural angle of sight of, 29 —Charges for, 62 —Pointing, 51. ICE: Strength of, 156. IMPLEMENTS: Quadrant, 18; breech-sight, 16; pendulum hausse, 17; gunner’s perpendicular, 18; pointing stakes, 57-8; pointing-wires, 56; plummet, 18, 58; pointing-cord, 57. INCENDIARY COMPOSITION, 117. INJURIES to cannon, 23. IRON preferred to bronze, 10. IRON CANNON used in land service, 10, 11. JUNK-WADS, 99. KNOB of cascable, 13; use of, 19. LACQUER, for iron guns, 160. LENGTH of cannon: Definition of, 11 —Extreme length, 12. LINE: Of fire, 64 —Of metal, 12; how directed, 52-3; not permanent, 54 —Artificial line of sight, 53. LIGHT BALLS, 92. LIMBERS: For field carriages, 126; for siege-carriages, 129. LOADING: With hot shot, 97 —Field shells, 100 —Spherical case, 101-2 —Mortar shells, 101-2 —Shells for columbiads and other heavy guns, 102.