388 



SUBJECT INDEX 



Paddle-boat, Papin's, 123 

 Parallax of star, 124, 201 

 Peltier effect, 274 

 Pendulum, 68 ff., 86; compound. 



Perpetual motion, 22, 233, 280 

 Philosophy and atomic theory, 179 

 Phlogiston, 129, 138 

 Phosphorescence, loi 

 Photo-electricity, 368 

 Photography, discovery of, 144 

 Photometer, Bunsen, 334 

 Physiology, 308 



PiW. 3 



Pile, voltaic, 164, 167 



Planetoids (Gauss), 241 



Planets, mass of, 92; motion of, 



40 

 Plants, discovery of breathing of. 



Polarisation, magnetic rotation of, 



258 

 Polarisation of light (Fresnel), 



208 f. 

 Potential, theory of (Gauss), 242 

 Principia, Newton's, 84, 94, 109 

 Proof plane, 157 

 Proper motion of stars, 124 

 Prutenische Tafeln, 17 

 Pump, Papin's, centrifugal, 121; 



explosion, 119; steam, 121 



Quantum theory, 355 flf. 



Radial velocity of stars, 332 

 Radiant matter, 346 f. 

 Radiation, Stefan's law of, 352 

 Radioactivity, 377 

 Radiometer, Crooke's, 349 

 Rainbow, theory of, 52 

 Refraction, double, 81; law of, 51 

 Rigid bodies, 2 

 Rings, Newton's, 104 



Saturn, 33, 73, 89 

 Self-induction, 255 flf., 372 

 Sidereal Messenger (Galileo), 32 

 Siemens' unit, 268 

 Silicon fluoride, discovery of, 145 

 Silver compounds, blackening by 

 light, 144 



Siphon recorder, 299 



Sound, 10, 59; velocity of, 95; wave 

 length of, 95 



Space, 2 



Space, ether, and energy, rela- 

 tionship between, 380 f. 



Species, classification of, 315 f.; 

 origin of, 317 flf. 



Spectrum analysis, 325 ff.; dis- 

 covery of, 181; of sun (Fraun- 

 hofer), 200 



Spirit and life, 313 



Spiritualism, 270 



Stars, spectrum of, 331 



Statics, 2 



Steam engine, Newcomen's, 123; 

 Papin's, 121 ; Watt's, i3oflF. 



Steel, alloys of (Faraday), 251 



Strontium, discovery of, 181 



Structural formulae, 337 



Submarine boat (Papin's), 121 



Sulphurous acid, discovery of, 145 



Sun, mass of, 92 



Sun-and-planet gear, 134 



Sun-spots, 33 



Tangent caivanometer, 266 

 Telegraph, electromagnetic, 264 

 Telescope, 30, 73; reflecting, 108 

 Tellurium, discovery of, 181 

 Temperature, absolute zero of, 183 

 Thallium, discovery of, 350 

 Theology, 98 

 Thermodynamics, laws of, 231; 



second law of, 296 f. 

 Thermoelectricity, 237 

 Thin plates, colours of (Newton 



and Fresnel), 104, 206 ff. 

 Thunderstorms, 154 

 Tides of the sea, 91 

 Titanium, discovery of, 181 

 Torsion balance, 148, 150 

 Triangulation, 51 

 Tungstic acid, Scheele's discovery 



of, 142 



Ultra-violet rays, discovery of, 



144 

 Ur aether, 380 



Uranium, discovery of, 181 

 Urea, synthesis of, 312 



