Molecular motion in liquids, 18 in gases, 13 in liquids and solids, 27 in solids, 31 Molecules, motion, 16 size, 13 Moment of force, 99, 133 Momentum, 87 law of, 92 Motion, 85 accelerated, 86 curvilinear, 88 direction, 86 first law, 87 modes, 85 second law, 92 third law, 93 uniformity, 86 Motor (electric), 339 A. C. series, 482 induction, 483 synchronous, 485 Muffler, 224 Musical instruments, 377 interval, 368 nomenclatures, table, 369 Musical sounds, characteristics 364 Newton's Laws of motion, 87 Nodes, in pipes, 384 in strings, 379 Noise and music, 363 Ohm, 294 Ohm's Law, 298 Opera glass, 428 Optical illusions, 390, 404 instruments, 423 camera, 426 eye, 423 microscope, 427 opera glass, 428 prism field glass, 429 projecting lantern, 427 telescope, 428 Organ pipes, closed, 384 nodes, 384 open, 384 Oscillatory discharge, 448 Osmosis, 19 Outline Review, current electricity, 325 force and motion, 118 heat, 227 induced currents, 353 light, 446 magnetism and static electricity, 266 sound, 387 work and energy, 158 Overtones, 379 Pascal's principle, 41 Pendulum, compound, 115 laws, 116 simple, 115 uses, 116 Pepper's ghost, 404 Permeability, 237 Phonograph, 383 Physics, definition, 4 Photometer, 394 Photometry, 393 Pitch, 365 Polarization, of light, 445 of voltaic cells, 273 Portraits, Bell, 431 Edison, 285 Faraday, 331 Galileo, 89 Gilbert, 217 Helmholtz, 397 Huygens, 397 Joule, 217 Kelvin, 331 Marconi, 431 Morse, 285 Newton, 89 Potential, 257 Power, 123 electric, 316 power factor, 476 transmission of electric, 476 water, 152 Pressure, air, 56 atmospheric, 58 Pressure, definition, 37 effect on liquids and gases, 62 law of liquid, 37 Prism field glass, 429 Projecting lantern, 427 Proof-plane, 244 Pulley, 139 Pumps, air, 66 condensing, 67 water (lift, 68, force, 69) Quality of musical tones, 380 Radiation, 176 sun's, 178 Radio-activity, 457 Radiometer, 177 Radium, 457 Rainbow, 436 Reactance, 472 Reflection, light, 396 multiple, 404 sound, 360 total of light, 413 Refraction, 410 cause, 412 index, 412 light, 410 in plates, prisms, and lenses, 413 Resolution of forces, 96 Resistance, cells in series, and parallel, 302 conductors, 293 in series and parallel, 299, 300 unit, 294 volt-ammeter method for finding, 304 Resonance, 371 Resonator, 373 Resultant, 81 Retentivity, 231 Right hand rule, 279 Rotary converter, 486 Science, definition, 2 Screw, 144 Shadows, 390 Single phase currents, 479 Siphon, 70 Siren, 366 Solidification, change of volume during, 203 Solutions, 27 Sound, compared with light, 388 interference, 374 media, 355 nature, 356 reflection, 360 rule for finding velocity, 367 source, 354 speed, 355 transmission in air, 359 Specific heat, 200 method of determining, 201 Spectroscope, 438