INDEX. 



415 



'Crystals, size of, 56. 

 (Yystallocenic forces, 50. 

 Crystalline bodies, magnetic influence 



of, 260. 



Ctidworth's " Plastic Nature," 10. 

 Current, electric, speed of, 231. 



, clrctricity, magnetic, 239. 

 Crystallization, 50. 

 Cultivation, limits of, 379. 

 Currents of electricity around the 



t earth, 224. 

 Cyanite, a true magnet, 48. 



DAGUEURE'S discovery, 170. 



Daguerreotype, the, 172. 



Dal ton on Aurora Borealis, 248. 



on liquefaction, 287- 

 Dalton's atomic theory, 278. 

 Daniel on incandescence, 100. 

 Dark lines of spectrum, 125. 

 Darwin on sea-weeds of the Southern 



Ocean, 316. 

 Davy, Sir H.. on the elements, 323. 



on llame, 307. 



discovers the alkaline metals, 325. 

 Decomposition, electro-chemical, 208. 

 De la Tour, Cagniard's experiments, 



105. 



Delaroche on heat, 93. 



Density of the earth, 31. 



Development, animal, 384 



Dew, formation of, 81. 



Diamond, allotropic carbon, 43. 



, phosphorescence of, 160. 



Diamagnetism, 253. 



Diamaijnetic nature of gases, 259. 



Diathermic bodies, 94. 



Diffusion of gases, 323. 



Digestion a cause of heat, 105. 



Dip of magnetic needle, 247. 



Dimorphism in crystals, 55. 



Directive power of a magnet on crys- 

 tals, 261. 



Distribution of elements. 328. 



Divisibility of matter, 38. 



Doebereiner's lamp, 281. 



Dispersion of light, ] 29. 



Draper on incandescence, 100. 



Dumas on atoms, 39. 

 Dust, a grain of, 2. 



EARTH, physical, the, 1. 



density of, 31. 



the revolution of the, 77- 



, geological formation of, 333. 



Earth's, motion, 11. 

 - temperature dependent on the 

 sun, 63. 



Effects produced by loss of heat, 69. 



Egs^s, number of, laid by insects, 399. 



Elective affinity, 292. 



Electricity, 193. . 



Electricity and light influencing crys- 

 tallization, 57. 



, kinds of, 195. 



contained in water, 203. 



developed by chemical action, 204. 

 , velocity of, 231. 



of plants, 380. 



Electric condition of matter, 5. 



telegraph, the, 231. 



affinity, 275. 



Electrical phosphorescence, 160. 



action influenced by actinism, 183. 



radiations, 190. 



clock, 233. 

 Electro-chemistry, 206. 

 Electro culture, 223. 

 Electrotype, the, 229. 

 Electro-chemical decomposition, 208. 

 Electro-magnetism, 240. 

 Electrum, 193. 



Elements, chemical, 37, 272. 



, atmospheric, 325. 



. interchanges of, 319. 



Englefield on heat rays, 67. 



Eocene formations, 346. 



Equinoxes, precession of the, 244. 

 | , the vernal and autumnal, 77. 

 ! Epicurus' hooked atoms, 48. 

 1 Epipolic phenomena, 129. 

 i Eremacausis, 105. 



Ether, hypothesis of an, 120. 



Examples of crystallization, 59. 



p]xpansion of bodies by heat, 96. 

 ; Eye, mechanism of, 491. 



