352 



INDEX. 



Sugar and semi-permeable membranes, 

 ,827 ; osmotic pressure of, 328 



Sulphate of quinine, absorption of radiant 

 energy by, 225 



Sulphur, boiling-point, 12 ; atomic 

 weight, 87 ; specific heat, 87 ; atomic 

 heat, 87 ; heat conductivity of, 103 ; 

 superfusion of, 201 ; sublimation of, 

 208 ; states of, 312 



Sulphuretted hydrogen, molecular 

 weight, 85 ; specific heat, 85 ; mole- 

 cular heat, 85 ; radiations absorbed 

 by, 235 



Sulphurous acid, molecular weight, 85 ; 

 specific heat, 85 ; molecular heat, 

 85 ; radiations absorbed by, 235 



Sun, temperature of, 12, 243 ; spectrum 

 of, 243 ; rate of radiation power, 251- 

 257 ; observations by Pouillet, 251- 

 253 ; Violle, 253-255 ; Langley, 253, 

 254, 256 ; Crova, 254, 256 ; Watter- 

 ston, 255 ; Rosetti, 255 ; Wilson and 

 Gray, 255 ; Wilson, 255, 256 



Supercooling of liquids, 201 



Superfusion, 201 



Snpersaturation, 207-208 



TAIT, heat conductivity of iron and other 

 metals, 98, 99 ; of earth, 107 



Tammann, on crystalline forms of ice, 207 



Tate. See Fairbairn and Tate 



Telepathy, 115 



Temperature, 2 ; Centigrade and Fahren- 

 heit scale of, 4 ; Reaumur's scale of, 

 5 ; of human body as a fixed point 

 for thermometric scales, 5 ; work 

 scale of, 9, 10, 266 et seq. ; absolute 

 scale of, 10, 266 et seq. ', air scale of, 

 10; hydrogen scale of, 11; electric 

 resistance scale of, 11 ; table of, 12 ; 

 slope or gradient of, 88, 93 ; re- 

 lation of, to pressure on gases, 138 ; 

 to loss of energy in evaporation, 

 162 ; uniform temperature en- 

 closures, 237-240 ; radiations at 

 different, 132, 243; radiation and, 

 244-257; variation of rate of 

 radiation with, 244-245 ; New- 

 ton's law of cooling, 245-246 ; 

 Dulong and Petit's law, 248 ; 

 Stefan's law, 250 ; temperature of 

 the sun, 255-257 ; relation of, to 

 entropy, 276-277, 287 ; to energy, 

 278 ; decrease of, with height in 

 the atmosphere, 296 



Thermal equilibrium, 2 



Thermodynamics, 258-342; first law 

 of, 128 ; second law, 258 ; the indi- 

 cator diagram, 259-260 ; isother- 

 mals, 260-261 ; adiabatics or isen- 

 tropics, 261 ; isopiestics and iso- 

 metrics, 261 ; heat engines, 261-266 ; 

 absolute or work scale of tempera- 



ture, 266-268 ; air thermomctei 

 scale, 269 - 270 ; non-reversible 

 cyclical engine, 270-271 ; reversible 

 engine, 271-272; reversible cycles, 

 272-273 ; entropy, 274-278 ; energy, 

 278-281 ; possible efficiency, of 

 a steam engine, 281-283 ; of iso- 

 thermal and adiabatic changes, 

 284-305 ; heat taken in by a body 

 expanding isothermally, 284-285 ; 

 adiabatic change, 285-305 ; specific 

 heats, 288-295 ; temperature of 

 change of state and solutions, 

 306-331 ; the first latent heat equa- 

 tion, 306-312 ; the second latent 

 heat equation, 312-314 ; alteration 

 of vapour pressure with curvature 

 of liquid, 314-317; hydrostatic 

 pressure in relation to vapour pres- 

 sure and melting-point, 317-320 ; 

 temperature of solutions, 320 et seq. ; 

 osmotic pressure, 320-321, 332 ; 

 raising of the boiling-point, 321-322; 

 lowering of the melting-point, 322- 

 327 ; semi-permeable membranes, 

 327-328; Van t'Hoff's application 

 of, 328-332 ; temperature of radia- 

 tion, 333-342 ; stream of energv, 

 334, 335 ; the fourth power law, 335- 



337 ; full radiation, 337-338 ; relation 

 between volume and temperature, 



338 ; entropy, 338 ; application of 

 Doppler's principle, 338-340 ; change 

 of energy in adiabatic expansion, 

 340-341 ; distribution of energy in 

 the spectrum, 341-342 



Thermo-electric thermometer, 11,12 

 Thermometer, use of, 2 ; contraction of, 

 3 ; fixing the points of a, 4-6 ; cali- 

 brating, 7 ; certificated, 7 ; pre- 

 cautions in using, 7 ; limits of 

 accuracy of, 8 ; range of the ordinary 

 mercury, 8, 9 ; platinum resistance, 

 11; thermo-electric, 11, 12; maxi- 

 mum and minimum, 13 ; gas, 48 ; 

 Regnault's normal air, 48-49 ; hy- 

 drogen, 49 ; Callendar's constant 

 volume, Bottomley's constant vol- 

 ume, 50 ; Bottomley's air, 50 ; con- 

 stant pressure gas, 50-51 ; Callendar's 

 compensating constant pressure, 51- 

 52 ; differential, 220-221 

 Thermopile, 221 



Thomson, J. , on the change from pas to 

 water, 187, 188 ; on influence of pres- 

 sure on melting-point, 203-309 

 Thomson and Joule, on intrinsic energy 



of air, 298 ft seq. 

 Thunder cloud formation, 57 

 Tilden, on specific heat of metals, 81 

 Tin, atomic weight, 87 ; specific heat, 

 87 ; atomic heat, 87 ; heat conduc- 

 tivity of, 100 ; electric conductivitv 



