  [The numbers refer to the paragraphs] Action and reaction equal, 182 Air, compressibility of, 152 Air, elasticity of, 161 Air, density of, dependent on pressure, 158 Air, pressure of, as affecting the boiling point, 171, 327 Air, currents in, from heat, 281 Air, solution of water in, 287 Air attracted by the earth, 148 Air in interstices of substances, 160 Air a non-conductor of heat, 302, 304 Air-pump, 155 Air-guns, 164 Animals, coverings suited to climate, 305 Archimedes, his lever, 229 Archimedes, his discovery in the bath, 138 Archimedes and the crown, 143 Artesian wells, 120 Aqueducts, 119 Atmosphere, pressure of, 154, 168 Atmosphere, how it moves with the earth, 188 Atomic theory, 15 Attraction, nature of, 53 Attraction, capillary, 72 Attraction between masses, 73 Attraction between solids and liquids, 69 Attraction, Newton's idea of, 54 Attraction, universality of, 77 Attraction, variety in results of, 87 Attraction, opposition between modes of, 88 Attraction, proportion of the mutual motions of, 76 Balloon, hydrostatic, 159 Barometer, 169 Barker's mill, 182 Battery, electrical, 387 Berkeley, his ideas of matter, 2 Boats, why they float, 139 Boiling point as affected by the pressure of the air, 171 Brittleness, 29 Buds in winter, 308 Bulk, relation of, to resistance of liquids and gases, 193 Camera obscura, 352 Canals, 117 Cartesian image, 159 Centre of gravity defined, 96 Centre of gravity, support of, in animals, 106 Centre of gravity, movements of, in walking, 107 Centre of gravity in relation to attitudes, 108 Centre of gravity in floating bodies, 145 Centrifugal force, 213 Centripetal force, 213 Chimneys, draught of, 282 Clothing, object of, 306 Clouds, how formed, 288 Clouds, colors of, 364 Clouds, shapes of, 289 Clouds, latent heat in, 324 Cocoons, constructed for winter, 307 Colors of objects, 363 Colors of the clouds, 364 Cohesion, strength of, 68 Cohesion, what is essential to it, 66 Cold, absence of heat, 270 Cold at great heights, cause of, 322 Cold from evaporation, 326 Compressibility of substances, 35 Compressibility of air, 152 Condenser, 162 Conductors of heat, 298 Conductors of electricity, 375 Conduction of heat, 297 Conduction, relation of density to, 300 Conduction in liquids, 301 Conduction, influence of, on sensation, 310 Convection of heat, 296 Coverings of animals suited to climate, 305 Crystallization, 62 Daguerreotype, 369 Dams, 122 Davy's safety-lamp, 299 Dawn explained, 346 Density, 24 Dew, formation of, 315 Dew-drops, colors in, 367 Dew-point, 317 Diatonic scale, 267 Draught of chimneys, 282 Drowning, how it can often be prevented, 141 Earth, globular form of, 61 Earth, roundness of, shown, 113 Earth, attraction toward centre of, 80 Earth, thickness of its air-covering, 150 Earth, shape of, influenced by centrifugal force, 218 Earth, rotation of, affecting winds, 284 Elasticity, 39 Elasticity, definition of, 42 Electricity, origin of the term, 370 Electricity, attraction and repulsion in, 371 Electricity, vitreous and resinous, 372 Electricity, galvanic, 394 Electricity, universality of, 378 Electricity, discharge of, from points, 383 Electricity, sound of, 389 Electricity, heat produced by, 391 Electricity, mechanical injuries by, 390 Electrics and non-electrics, 377 Electrical battery, 387 Electro-magnetism, 413 Electro-magnets, 414 Electric telegraph, 415 Equestrian feat, 185 Equilibrium, stable and unstable, 109 Evaporation, 286 Evaporation, cold produced by, 326 Expansion by heat, 274 Expansion, exception to it, 330, 331 Extension, a property of matter, 44 Eye, description of, 353 Eye, images in, inverted, 356 Feathers, how a non-conductor of heat, 305 Fire-engine, 179 Flexibility, 29 Flies, feet of, 157 Force, relation of, to velocity, 194 Forcing-pumps, 178 Franklin, his discovery, 392 Freezing, process of, described, 330 Freezing point, why at 32°, 332 Freezing in the midst of boiling, 327 Freezing mercury, 318 Freezing mixtures, 325 Friction, 196-198 Friction in machinery, 245 Frost, 44 Fur, how a non-conductor of heat, 305 Fur, how altered by climate, 305 Fusee of a watch, 238 Galvanism, 394 Gases, movements of the particles in, 10 Gases, space in, 21 Gases, compressibility of, 38 Gasometer, 163 Glass, annealing of, 32 Glass-making, centrifugal force used in, 216 Governor, steam, 217 Gravitation, limiting size, 90 Gravitation, action of, on solids in a liquid, 136 Gravity, specific, defined, 135 Gridiron pendulum, 210 Gunnery, retardation by condensed air in, 166 Hail, how produced, 290 Hardness, 28 Harmony, 266 Hearing, mysteries of, 269 Hearing, trumpet, 262 Heat, nature of, 271 Heat, sources of, 272 Heat, relations of, to forms of matter, 13 Heat, relation of, to bulk of liquids, 37 Heat, relation of, to light, 273 Heat producing expansion, 274, 275, 279 Heat, communication of, 295 Heat, convection of, 296 Heat, conduction of, 297 Heat, radiation of, 311 Heat, reflection of, 314 Heat, connection of, with light, 312 Heat, production of, by electricity, 391 Heat, degree of, endurable by man, 328 Heat, latent, 319 Heat, capacity of different substances for, 320 Heat, relation of, to density, 321 Heat, relation of, to forms of substances, 323 Heat and cold, 270 Heights measured by barometer, 170 Hume, his ideas of matter, 3 Hydrometer, 144 Hydrostatics, what it teaches, 110 Hydrostatic balloon, 159 Hydrostatic bellows, 132 Hydrostatic paradox, 131 Hydrostatic press, 133 Ice, formation of, 329 Ice, force of its expansion, 333 Ice-crystals, colors in, 367 Icebergs, centre of gravity in, 145 Impenetrability, 45 Imponderable agents, 16 Inclined plane, 241 Induction in electricity, 379 Induction in magnetism, 400 Inertia, 48 Inertia shown in the communication of motion, 183 Inertia shown in disposition of motion to continue, 184 Insulating stool, 382 Jupiter, mountains in, 92 Laggan stones, 100 Land-breeze, 283 Lenses, 349 Lever of first kind, 224 Lever, no gain of power in it, 227 Lever of second kind, 231 Lever of third kind, 232 Life-boats, 139 Light, nature of, 334 Light, sources of, 335 Light, diffusion of, 337 Light, velocity of, 338 Light, reflection of, 340 Light, refraction of, 345 Light moves in straight lines, 336 Light shown to be compound, 360 Light, colors in, 360 Light, recomposition of, 362 Light, chemistry of, 369 Lightning-rods, 393 Liquids, movability of their particles, 9, 57 Liquids, incompressibility of, 36 Liquids, attraction in, 56 Liquids, globular shape of drops of, 58 Liquids, cause of level surface of, 111 Liquids, pressure of, in proportion to depth, 121 Liquids, lateral pressure of, 123 Liquids, pressure of, equal in all directions, 125 Liquids, upward pressure as depth, 127 Liquids, in what like gases, 153 Liquids, friction of, in tubes, 197 Liquids, friction of, in streams, 198 Liquids, expansion of, by heat, 275 Loadstones, 397 Machines not sources of power, 222 Machinery, friction in, 245 Magic lantern, 351 Magdeburg hemispheres, 156 Magnetism, origin of term, 397 Magnetism, attraction of, 398 Magnetism, repulsion of, 401 Magnet, poles of, 399 Magnets, artificial, 403 Magnets, horseshoe, 404 Magnetic needle, 405 Malleability, 28 Man a tool-making animal, 247 Mariner's compass, 405 Matter distinguished from spirit, 1 Matter, effects of, on senses, 6 Matter, forms of, 7 Matter, nature of, 14 Matter, constitution of, 14 Matter, variety in properties of, 17 Matter, divisibility of, 18, 51 Matter, minute division of, 19 Matter, pores and spaces in, 22 Matter, relation of heat to spaces of, 23 Matter, inertia of, 48 Matter, impenetrability of, 45 Matter equally inclined to rest and motion, 50 Mechanical powers, real advantages of, 246 Mercury, freezing of, 318 Microscopes, 350 Microscopical animals, 19 Mirages, 347 Mirrors, 342 Mirrors, curved, 344 Moth's wing, 19 Motion, causes of, 181 Motion, universality of, 180 Motion, absolute and relative, 191 Motion, obstacles to, 192 Motion, reflection of, 206 Motion, compound, 212 Motion, curved, 213 Motion in orbits, 221 Motion disposed to be straight, 211 Motion, that of falling bodies projectile, 220 Momentum, 201 Mountains, size limited, 92 Nature, order in, 65 Near-sightedness, 355 Needle, magnetic, 399 Needle, declination of, 406 Needle, dip of, 407 Noise, how it differs from musical sound, 263 Non-conductors of heat, 298 Non-conductors of electricity, 375 Notes, musical, how produced, 264 Odors, minuteness of their particles, 19 Order in nature, 65 Papin's digester, 292 Pendulum, 208-210 Perpetual motion attempted, 118 Persia, accident to, 274 Pisa, tower of, 104 Pitchers, why they have lips, 89 Pneumatics, what it teaches, 146 Pneumatic trough, 167 Pop-guns, 164 Pottery, centrifugal force used in, 216 Powder, explosive force of, 165 Prince Rupert's drops, 33 Pulleys, 239 Pumps, 176 Pumps, forcing, 178 Radiation of heat, 311 Radiation, its relation to absorption, 313 Rain, how it is caused, 290 Rarity, 24 Reaction equal to action, 182 Reflection of heat, 314 Reflection of light, 340 Reflection of motion, 206 Reflection of sound, 260 Remora, 157 Rest, merely relative, 189 Rivers, bends in, 215 Roemer, observations of, in regard to the velocity of light, 339 Rope-dancers, skill of, in managing centre of gravity, 109 Safety-lamp, 299 Screw, 243 Sea-breeze, 283 See-saw, a lever, 228 Sensation, influence of the conduction of heat on, 310 Shape, relation of, to velocity, 195 Shot, manufacture of, 60 Signal key, 415 Silk-worm, thread of, 19 Size limited by gravity, 90 Sluice-gates, 122 Snow, how produced, 290 Snow, crystals of, 64 Snow a protection to plants, 309 Solids, constitution of, 8 Solids, attraction in, 39 Sound, what it is, 248 Sound, sensation of, how produced, 252 Sound, velocity of, 256 Sound, transmission of, 253 Sound, loudness of, 258 Sound, diffusion of, 259 Sound, reflection of, 260 Sound, concentration of, 262 Sound, none produced by the heavenly bodies, 255 Speaking-trumpet, 262 Specific gravity defined, 135 Specific gravity of animals, 140 Specific gravity of the human body, 141 Specific gravity of liquids, how ascertained, 144 Spectrum, 360 Spider, web of, 19 Spirit distinguished from matter, 1 Spirit, origin of word, 4 Spirit-level, 114 Springs, 120 Stability of bodies, 103-105 Steam transparent and invisible, 293 Steam, expansive force of, 165 Steam-engine, 294 Steel, flexible and brittle, 30 Steel, tempering of, 31 Stereoscope, 358 Suckers, 157 Sucking, explanation of, 167 Suction, 177 Sulzer's experiment, 394 Sun as a source of heat, 272 Surface, relation of, to movability, 193 Syphon, 172 Tantalus, cup of, 174 Telegraph, 415 Telescopes, 350 Tenacity, 25 Tenacity, comparative, of substances, 26 Tenacious substances, value of, 27 Thermometer, Fahrenheit's, 277 Tides, 78 Tubes, friction of liquids in, 197 Twilight explained, 346 Unison, 268 Up and down, explanation of, 81 Vapor, influence of pressure upon the formation of, 292 Vaporization, 291 Velocity, relation of, to force, 194 Velocity, relation of, to shape, 195 Velocities, great, how produced, 203 Velocities, great, how arrested, 204 Vibration of sounding bodies, 249 Vision, distinct, what necessary to, 354 Vision, why single, 357 Vision, why erect, 356 Visual angle, 348 Voice, how produced, 265 Voltaic electricity, 394 Volta's pile, 395 Walrus, feet of, 157 Water, crystallization of, 63 Water man's first mirror, 112 Waves, how formed, 199 Waves, height of, 200 Wedge, 242 Wheel and Axle, 235 Wheel-barrow a lever, 231 Whispering galleries, 261 Windlass, 236 Windows, double, 303 Winds, 283 Winds as affected by the rotation of the earth, 284 THE END. |
|
