RANGES: Definition, 63 —Point-blank, 63 —British point-blank, 63 —Causes which vary point-blank, 64 —Extreme range, 66 —Angle of greatest range _in vacuo_, 66 —Tables of, 68-9, 70-1-2 —How ascertained, 149. RATE OF MARCH of horse-artillery, cavalry, and infantry, 153. RECOIL: Definition, 77 —Cause of, 77 —Amount, 77 —Has no appreciable effect on flight of projectile, 78 —Influence of position of axis of trunnions on, 78-9. REINFORCE, 13 —Band, 13. RESISTANCE OF AIR to projectiles, 147-8. RICOCHET: Definition, 73 —Object of, 73 —How conducted, 74-5 —Advantages of, 73 —Nature of, 75 —Charges for a _flattened_ ricochet, 76; for _curvated_, 76 —Tables of ricochet firing, 76 —Pieces best adapted for, 75 —Distance from object of ricochet battery, 74 —Greatest angle of elevation for ricochet firing, 74. RIFLE-CANNON: Experiments at Fort Monroe, 166-7 —Armstrong gun, 165. RIMBASES, 14. RING WADS, 94. RIVERS: Breadth, 156-7. ROPES: size and strength of, 156. SABOTS: Difference in, for field service, 93 —Arrangement for field guns and 12-pdr. field howitzer, 93; in 24 and 32-pdr. field howitzers, 93 —Mode of fastening sabots to projectiles for field-service, 93-4; for heavy shells, 94; for canisters, 94-5; for grape shot, 95. SEA-COAST PIECES, how mounted, 35 —Number and kind required for sea-board forts, 35 —Heavy sea-coast mortar-bed, 131-2. SCALING a piece, 21. SHOT: Solid, 90 —Hollow, 90 —Rule for finding weights and diameters of cast-iron shot, 95 —Condemned shot, how marked, 102 —Piling, 103-4 —Preservation, 102-3 —Forces acting on a shot, 51 —Penetration, 149-50 —Time required to heat, 97-8 —Expansion of by heat, 96 —Ranges of, 68-72 —Method of driving out shot wedged in the bore, 21 —Velocity of, 147. SHELLS, 90; —Dimensions and weights, 106-7 —Mode of computing weight of, 95 —Quantity of powder to fill, 96 —Strapping, 93 —Loading, 100-1-2 —Ranges, 68-72 —Condemned, how marked,102 —Velocity, 147. SIGHTS of a piece: Definition, 12 —How determined, 12 —Quarter, 16. SIEGE ARTILLERY: Kinds, 36 —Proportions in a siege train, 36; of carriages, 36-7; draught horses, 37; projectiles and ammunition, 37-8 —Siege mortar-beds, 130-1. SLING-CART: Hand, 146. SLOW MATCH, 116. SMOKE BALLS, 93. SOUND: Velocity, 151 —Distance determined by, 151. SPECIFIC GRAVITY, 159. SPHERICAL CASE, 90 —Loading, 100-1. SPIKING cannon, 20. STAKES, pointing: How planted, 57-8. STONE MORTAR: Length, 33 —Weight, 33 —Calibre, 33 —Length of bore, 33 —Length of chamber, 33