=Solids=, a condition or state of matter, 73 =Socket-wrench=, def., 29 =Spanner=, def., 29 =Specific gravity of liquids=, 96 of steam, 286 rule for finding the, of a solid body, 95 standard for, 91 tables, rule to find weight of anything in, 97 =Spline or feather=, def., 29 =Split-pin or cutter=, def., 29 =Spray pump=, ills. and des., 201 “=Spread=,” def., 29 =Spring, a conical=, employed to hold the valve to its seat, 209 =Spring-seat=, def., 29 =Springs, valve, guards and covers= for the underwriter pump, 376 =Standard, National=, specification for the manufacture of steam fire pumps, 351 =Statics=, def., 244 what it treats of, 74 electricity, 244 =Steam end of a pump=, def., 30, 279-285 of the underwriter steam fire pump, details of, 356-366 =Steam engines, compound=, adapted to pump, 70 =Steam fire pumps, to be started once a week=, 377 =Steam gas=, def., 286 =history of steam and the steam engine=, 280 how produced, 285 or power ends of pumps, 209 parts of the underwriter steam fire pump, 356 properties of, explanation, 281-285 properties which make it valuable, 286 =Steam pump=, ills. and early patent of H. R. Worthington, 278-330 how classified, 188 why so called, 187 =Steam, relative volume of=, diagram, 282 specific gravity of, 286 thrown valves, def., 30 total heat of, 286 useful definitions relating to, 285-286 =Steel=, specific gravity of, 96 =Stems, valve=, of the underwriter pump, 379 =Step= for water wheel, danger of heating, 137 “=Sticking of valves=,” def., 30 des., 377 =Strainer=, def., 30 foot valve, ills. and des., 223 for suction pipe, ills., 204 for tube wells, ills. and des., 203 =Streams, velocities of=, ills., 110 =“Stroke” of pump=, def., 30 =Stub-end=, def., 30 =Stud-bolt=, def., 30 =Stuffing-box=, def., 30 and gland, ills. and des., 211 of the underwriter steam fire pump, 365 =Submerged pump=, def., 30 =Sucker-rod=, couplings, des. and ills., 203, 204 “=Sucking wind=,” def., 31 =Suction and force pumps=, classification of, 187 glass models of, 181 two-cylinder, arranged with extension levers, ills., 196 =Suction-force pump= with air chamber, ills. and des., 226 =Suction or lift pumps=, classification of, 187 pump, for vessels, ills., 193 pipe, how made and placed, 204 pipe, proper, ills. and des., 223 valve area of the underwriter pump, 373 of the Riedler express pump, peculiarities of, 240 =Sulphur=, specific gravity of, 96 =Superheated steam=, def., 286 =Supplemental piston=, def., 31 =Supply channel=, leading water from falls, 119 =Swape or sweep=, historical ref. and ills., 48 =Swing check valve=, def., 31 =Switch=, automatic, 269 =Switch-cock or valve=, def., 31 =Switches and switch boards=, des. and ills., 254-255