Note.—Figures in italics signify that an illustration of
the thing referred to appears on the page.

Aberration, spherical, of lens, 243.
Acoustics, 294.
Achromatic lens, 243.
Action carriage of piano, 283.
Advancing the spark, 102.
Air-gun, 342.
Air-pump for cycle tyres, 340;
for Westinghouse brake, 199.
Alternating currents, 164;
dynamo, 164.
Amperage, 125.
Angle of advance, 57, 58;
incidence, 268;
reflection, 268.
Aorta, 360.
Arc lamp, 182.
Archimedes, 412.
Armature, 162.
Arteries, 358.
Arterial blood, 359.
Atmospheric pressure, 350.
Auditory nerve, 272.
Automatic brakes, 188;
signalling, 228;
stoker, 399.
Backfall, 298.
Balance-wheel, 419.
Ball cock, 366, 367.
Balloon, fire, 323;
gas, 347.
Barometer, aneroid, 328, 329;
and weather, 331;
Fortin's, 326;
meaning of, 325;
simple, 328;
wheel, 327.
Beau de Rochas, 89.
Bell, diving, 332;
electric, 119, 120.
Bellows of organ, 303.
Bioscope, 266.
Blades, turbine, 81, 83.
Block system, 201, 212.
Blood, arterial, 359;
circulation of, 356, 357, 360;
venous, 359.
Blower-plate, 393, 394.
Boat, sails of, 346.
Boiler, Babcock and Wilcox, 21, 22;
explosions, 34, 391;
fire-tube, 21;
fittings, 31;
Lancashire, 25, 26;
locomotive, 20, 23;
multitubular, 21;
principle of, 15;
stored energy in, 32;
vertical, 25;
water supply to, 39;
water-tube, 21.
Brakes, hydraulic, 188;
motor car, 110;
railway, 187;
vacuum, 189, 190, 191;
Westinghouse, 194, 195, 197.
Bramah, 363, 437.
Breezes, land and sea, 324.
Brushes of dynamo, 161, 172.
Bunsen burner, 409.
Burning-glass, 232.
Camera, the, 233;
pinhole, 234, 235.
Canals, semicircular, 273.
Capillary attraction, 392;
veins, 358.
Carbon dioxide, 27, 359;
monoxide, 27.
Carburetter, 98, 99.
Cardan shaft, 93.
Carmania, the, 83.
Centrifugal force, 382.
Change-speed gear, 105, 442.
Chassis of motor car, 92.
Circulation of water in a boiler, 17, 18, 19;
of water in a motor car, 95, 97.
Clarionet, 308.
Clock, first weight-driven, 412;
water, 410.
Clutch of motor car, 105.
Coal, as fuel, 15;
gas, 394;
gas making, 394;
gas plant, 396;
gas, purification of, 397.
Cochlea, 273.
Coherer, 140.
Coil, Ruhmkorff, 121.
Coke, 395.
Combinations in Chubb lock, 436;
Yale lock, 436.
Combustion, 26, 393;
perfect, 28.
Compensating gear, 107, 108.
Compound engines, 59;
arrangement of, 61;
invention of, 59.
Compound locomotives, 62.
Compound microscope, 261.
Condenser, marine, 71, 72;
of Ruhmkorff coil, 123.
Conduit, 176.
Convex lens, image cast by, 236.
Conjugate foci, 262.
Cornet, 308.
Corti, rods of, 274.
Coxwell, 348.
Cream separator, 381, 383.
Current, reversal of electric, 130, 131;
transformation of, 124.
Cushioning of steam, 55.
Cycle, gearing of, 439.
Cylinder, hydraulic press, 363;
steam, 49.
Danes, 382.
Dead point, 47.
De Brouwer stoker, 401.
Detector in Chubb lock, 435.
Diving-bell, 332;
simple, 333, 334.
Diving-dress, 335.
Direction of current in dynamo circuit, 163.
Diver's feats, 338;
helmet, 336;
lamp, 338.
Donkey-engines, 68.
Doorstop, self-closing, 344.
Double-cylinder engines, 47.
Draught, forced, 28, 29;
induced, 29.
Drum and fusee, 414.
Durability of motor-car engine, 96.
D-valve, 67.
Dynamo, alternating, 164, 174;
brushes, 172;
compound, 174;
continuous-current, 165;
multipolar, 169;
series wound, 173;
shunt wound, 173;
simple, 161, 162.
Ear, the, 271, 273;
a good, 274, 307;
sensitiveness of, 275.
Eccentric, 52, 53;
setting of, 53.
Edison, Thomas, 310.
Edison-Bell phonograph, 310.
Electricity, current, 115;
forms of, 113;
nature of, 112;
static, 114.
Electric bell, 119, 120;
signalling, 225;
slot, 226.
Electroplating, 185, 186.
Electro-magnets, 117.
Endolymph, 272.
Engines, compound, 59;
donkey, 68;
double-cylinder, 47;
internal-combustion, 87, 95;
reciprocating, 44.
Escapement of timepieces, 416;
cylinder, 420;
lever, 421, 422.
Ether, 270.
Eustachian tube, 276.
Eye, human, 246, 247;
self-accommodation of, 248.
Expansive working of steam, 56.
Faraday, Michael, 159.
Field, magnetic, 159;
magnets, 171;
ring, 174.
Filters, 374;
Maignen, 373;
Berkefeld, 374.
Filtration beds, 372.
Flute, 308.
Flying-machines, 348.
Fly-wheel, use of, 48.
Focus, meaning of, 237;
principal, 238.
Foci, conjugate, 262.
Force, lines of, 116.
Forces, component, 345.
Free wheel, 440.
Furring-up of pipes, 391.
Fusee, drum and, 414.
Galileo, 259, 325, 416.
Galilean telescope, 259.
Gas, coal, 394;
governor, 402;
meter, 405;
traps, 374;
works, 394.
Gasometer, 397;
largest, 398, 399.
Gauge, steam, 36, 38;
water, 35, 36.
Gear, compensating, 107, 108.
Gear-box of motor car, 105.
Gearing of cycle, 439.
Glaisher, 348.
Gland, 50, 363.
Glass, flint and crown, 242.
Going-barrel for watches, 415.
Gooch reversing gear, 65.
Governors, speed, 67;
of motor car, 103, 104.
Graham, 418.
Gramophone, 317;
records, 319, 321;
reproducer, 318.
Hairspring, 412.
Hay-cutter, 451.
Heart, the, 355;
disease, 361;
rate of pulsation of, 361;
size of, 357.
Heat of sun, 451.
Hele, Peter, 412.
Helmet, diver's, 336.
Helmholtz, 274, 308.
Hero of Ale 01;
open, 292;
organ, 295;
reed, 301, 302;
tuning, 302.
Piston valve, 67.
Pneumatic tyres, 341.
Poldhu, signalling station at, 138.
Points, railway, 208, 210;
and signals in combination, 211.
Poles of a magnet, 115.
Popoff, Professor A., 138, 145.
Power, transmission of, 175.
Preece, Sir William, 145.
Primary winding of induction coil, 122.
Pump, air, 340;
bucket, 352, 353;
force, 354;
most marvellous, 355;
Westinghouse air, 199.
Railway brakes, 187;
signalling, 200.
Rays, converging and diverging, 256;
heat, concentrated by lens, 232;
light, 232, 235, 236, 237.
Records, master, 319, 320.
Reciprocation, 51.
Reed, human, 306;
pipes, 301, 302.
Reflecting telescope, 260.
Relays, telegraphic, 133, 141.
Retina, 247.
Retorts, 395.
Reversing gear, 62;
Allan, 65;
Gooch, 65;
radial, 66.
Rocking bar mechanism for watches, 425.
Rods of Corti, 274.
Ruhmkorff coil, 121, 122.
Safety-valve, 32, 33, 391.
Sand-glasses, 411.
Scissors, action of, 450.
Secondary winding of induction coil, 122.
Series arrangement of electric lamps, 183.
Series winding of dynamo, 173.
Shunt wound dynamo, 173.
Sight, long and short, 250.
Signalling, automatic, 228;
electric, 272.
Wireless telegraphy, 137;
advance of, 145;
receiver, 140, 141;
syntonic, 143;
transmitter, 138, 139.
Yale lock, 436, 437.
Yellow spot, in eye, 251.
Zech, Jacob, 414.
Zeiss field-glasses, 260.

THE END.