INDEX. 



56i 



Stefan (J.) on the velocity of the pro- 

 pagation of sound in gaseous bodies, 

 490. 



Stewart (B.) on the history of spec- 

 trum analysis, 354 ; on the forces 

 concerned in producing the larger 

 magnetic disturbances, 480. 



Stokes (Prof. G. G.) on the long spec- 

 trum of electric light, 310. 



Sulphur, on some modifications of, 

 212. 



Sun's heat, on the measure of the, 

 244 ; on the origin of the, 392, 460. 



Surfaces, on a theorem relating to, 61 . 



Sylvester (Prof. J. J.) on theorems 

 relating to canonic roots, 453. 



Tactics, on, 59. 



Tait (Prof. P. G.) on the conservation 

 of energy, 263, 429. 



Taltalite, on the constitution of, 111. 



Tate (T.) on the law of expansion of 

 superheated steam, 65 ; on the laws 

 of evaporation and absorption, 331. 



Telescopes, on the forms of lenses 

 proper for the negative eyepieces 

 of, 155. 



Thallium, observations on, 210 ; on 

 the crystalline form and optical 

 properties of sulphate of, 24S. 



Thermometer, on a new and sensitive, 

 320. 



Thomson (Prof. W.) on the secular 

 cooling of the earth, 1 ; on the 

 rigidity of the earth, 149 ; on the 

 dynamical theory of heat, 429 ; on 

 the thermal effects of fluids in mo- 

 tion, 486. 



Tidal wave, on the, 531. 



Tomlinson (C.) on the motion of cam- 



phor towards the light, 114, 492; 

 on the motion of vapours toward 

 the cold, 360. 



Topaz, on the pressure cavities in, 1 74. 



Triangle, line, and conic, on a theorem 

 relating to a, 181. 



Tschermak(Dr.) on some specimens of 

 pseudomorphs, 323 ; on the origin 

 of amygdaloid rocks, 491. 



Tungstates, on the constitution of the, 

 213. 



Tyndall (Prof.) on radiation through 

 the earth's atmosphere, 200; on 

 the dynamical theory of heat, 220, 

 368. 



Vapour, on the diffusion of, in the air, 

 339. 



Vapours, on the motion of, toward the 

 cold, 321, 360. 



Varley (C. F.) on the relative speed 

 of the electric wave through sub- 

 marine cables, 548. 



Verdet (M.) on the history of the 

 mechanical theory of heat, 46/. 



"Water, on the dissociation of, 536. 



Wealden deposits of England and 

 France, on the, 268. 



"Willich (C. M.) on some remarkable 

 numerical approximations, 411. 



Wohler (Prof.) on a new oxide of sili- 

 con, 539. 



Wood (S. V.) on the events which 

 produced and terminated the Pur- 

 beck and Wealden deposits of En- 

 gland and France, 268. 



Woods (Dr. T.) on the motion of va- 

 pours toward the cold, 321. 



Zodiacal light, on the, 117, 183. 



END OF THE TWENTY-FIFTH VOLUME. 



