INDEX TO VOLUME XX. 



Academy of Natural Sciences of Phila- 

 delphia, 414. 



Academy of Sciences of St. Petersburgh, 

 389. 



Acetate of morphine, 184. 



Acetic acid, crystallizable, 186. 



Achromatic microscope, 265. 



Addition to Prof. Johnson's article, 418. 



Aikin's Dictionary of Chemistry, 93. 



Aldini, Ch., on protection from flame, 96. 



Alum in mica slate, 418. 



Aluminium, preparation of, 408. 



American Birds, new work on, 161. 



American Botanical Register, 160. 



Analysis of Black Sea, 188. , 



Brewsterite, 198. 



the Protogea of Leibnitz, 56. 



Analytical geometry, 285. 



Angina pectoris, use of iodine in, 411. 



Anthracite mines, 165. 



Antique medals found near Geneva, 391. 



Arsenic in sea-salt, 193. 



Asbestos impregnated'with platinum, 160. 



Asparagin, 187. 



Atholl, Duke of, notice concerning, 307. 



Atlantic coast, prevailing storms of, 17. 



Atmosphere, carbonic acid in, 183. 



Augite, affinity of to the Diallage family, 

 168. 



Aurora borealis seen at Paris, 396. 



Austria, rail roads in, 174. 



Azotic gas in warm springs, 383. 



B. 



Babbage, Prof., on the decline of Science 



in England, 164, 172. 

 Bache, A. D., Prof, on a safety apparatus 



for steam boats, 317. 

 Bakewell, R, on the salt springs of Mou 



tiers, 219. 

 Berlin, history of, 389. 

 Berzelius, his System of Chemistry, 95. 

 Betuline, a supposed new principle in 



birch, 282. 

 Birds, American, a new work on, 161. 



Birch, bark of, containing a supposed new 



principle, 282. 

 Black Sea, analysis of, 188. 

 Bloodgood, S. De Witt, on Halos, 297, 

 Bone caves in New Holland, 380. 

 Bones, fossil, from Kentucky, 370. 

 Bonnycastle, Capt. on the geology of the 



Cataraqui, 74. 

 Bored wells, 392. 

 Boston Mechanics' Magazine, 160. 

 Botanic Garden of St. Petersburgh, 175 

 Branch mint in North Carolina, 401. 

 Brande's Manual of Chemistry, 88 

 Brewsterite, analysis of, 198. 

 Bromine, preparation of, 194. 



in salt works at Hingham, 161 



Bronn, Prof., his proposal to exchange pet- 

 rifactions, 397. 

 Browne, H. Mr., notice of, 307- 

 Buffalo mineral spring, 156. 



Canada, literary and scientific societias of, 



168. 

 Caoutchouc, electrical properties of, 404, 

 Carbon, crystallized, 167. 

 Carbonic acid in the air, 183. 

 Carburetted hydrogen gas, as fuel for 



steam boilers, 10. 



decomposition of, 186. 



Carpenter, G. W., on Peruvian Bark, 52. 



Cass, Gov., on the tides at Green Bay, 217. 



Cataraqui, geology of, 74. 



Cassius, the purple powder of, 192. 



Central forces, 65, 291. 



Chalybeate water, a remarkable one, 384, 



Charring of wood, 189. 



Chenevix, M., notice of, 305. 



Chile, plants of, 248. 



Chloride of silver, 193. 



Christie, Dr., reply to, by Prof. Olmsted, 



373. 

 Chromate of potash, pure, 409. 

 Chronometers, purification of oil for, 166, 

 Cinchonia, remarks upon, 52. 

 Clemson, T. G., on the manufacture of 



Sulphuric acid, 347. 



