INDEX. 



421 



Thermo-electricity, 209. 



Theory of motion producing force, 15. 



Thilorier on solid carbonic acid, 111. 



Time, influence of, 332. 



Tissues, catalytic power of, 310. 



Tourmaline, action of, on light, 142. 



Trade winds, 81. 



Transition series of rocks, 336. 



Transparency, calorific, 67. 



, luminous, 124. 



Transmutation of matter, 37. 



Transmission of light, 128. 



Transcalescent bodies, 94. 



Trevelyan, Mr., on vibration of heated 

 metals, 97. 



Tyndale proves the influence of struc- 

 ture on magnetism, 258. 



Type, elements of the organic, 289. 



UNDULATIONS producing colour, 131. 

 Undulatory theory of heat, 115. 

 theory of light, 121. 

 Uranus, discovery of, 31. 

 Uranium glass, influence of, on light, 

 129. 



VAPOUR, elastic force of, 318. 

 Variation, magnetic, 244. 

 Vegetables conductors of electricity, 



379. 



Vegetable life, phenomena of, 357. 

 Vegetation of carboniferous epoch, 339. 

 Velocity of electricity, 231. 

 Vertebrate animals, 390. 



Vision, phenomena of, 148. 



Vis vitse, vital principle, 391. 



Vision single with a pair of eyes, 150. 



Vitality superior to physical force, 53. 



Vision, seat of, 149. 



Volume, doctrine of, 287- 



Volcanic action referred to chemical 



action, 271. 



Volatilization of matter, 27. 

 Voltaic electricity, 201 . 



WATER, absorption of heat by, 74. 



frozen free of air, 112. 



free of air, peculiar state of, 113. 

 , electricity in a drop of, 204. 



composition of, 296. 

 Wargentin's notice of aurora, 248. 

 Wave movement of heat and light, 



68. 



Wealden formations, 343. 



Wedgwood on incandescence, 100. 



Wells, Dr., on dew, 84. 



Wiedman on electrical vibrations, 257. 



Wenzel's proportional numbers, 277. 



Winds dependent on heat, 80. 



Wollaston notices dark lines in spec- 

 trum, 125. 



World, its age, 404. 



YOUNG on molecular forces, 49. 



ZODIACAL light, 25. 

 Zoophytes, microscopic, 387. 



THE END. 



Wilson and Ogilvy, 57, Skinner Street, Snowhill, London. 



