Opium, constitution of, xxviii, 359. ----, mode of detecting minute quantities of, _R. Hare_, xii, 290. ----, observations and experiments on, _G. W. Carpenter_, xiii, 17. ----, English, viii, 389; x, 194. ----, paramorphine in, xxiv, 374. ----, thebaine in, xxx, 379. Opossum, remains in the Stonesfield slate, xxvii, 412; xxxvii, 228. Optics, notice of _D. Brewster's_ Treatise on, xxiv, 389. Optical amusements, xvi, 398. ---- experiment, exhibiting the blood vessels of the eye, xxi, 166. ---- deception, instrument for exhibiting a certain, _E. S. Snell_, xxvii, 310. ---- instruments, xix, 390. ---- properties of saccharine juice, _Biot_, xxiv, 379. ---- structure of minerals, notice of, ix, 384. ---- surgery, xviii, 179. ---- trap, v, 200. Orang Outang, account of, xv, 161. Orange County of New York, natural history of, _J. Van Rensselaer_, xiii, 224. ----, mineral notices of, _C. U. Shepard_, xxi, 321.^f ----, ---- ----, _J. Fowler_, ix, 242. Orangeries, v, 190. Orchis tribe, synonymy of some species of, _A. Gray_, xxxviii, 306. ---- spectabilis, monstrous flower of, _J. W. Bailey_, xxxv, 117.^f _Ordinaire, J. J._, method of teaching Latin used by, v, 182; vii, 383. ----, on public instruction, vii, 199, 383. Oregon, fossil bones from, _H. C. Perkins_, xlii, 136.^f ----, fossil bones from, orycterotherium, &c., _R. Harlan_, xliv, 79. ----, geological and miscellaneous remarks on, _J. Ball_, xxviii, 1. ----, climate of, and a meteorological register kept at Fort Vancouver, 1832, 1833, J. Ball, xxviii, 8. Orenburg, salt steppe of, xliv, 205. Orford brown tourmaline, xxxiv, 204. Organic remains, see _Fossil_. _Oriani, B._, death of, xxv, 186. Orientals, style of, v, 181. Oriental minerals, _F. Hall_, xxxiii, 249. Ornithichnites, see _Footprints_. Ornithological terms, improved, xxi, 162. Ornithology, work on, by _T. Nuttall_, noticed, xx, 154; xxii, 178; xxv, 424. ----, see farther under _Zoology_. _Orr, I._, on the process of memory, xxiii, 278. ----, on the formation of the universe, vi, 128.^f ----, on infinites, v, 326. ----, mathematical propositions by, xxiv, 395. Orthite, ix, 376. Orthocerata, see ZOOLOGY, _Mollusca_. Orthography, English, proposals for improving, xxxix, 197. Orycterotherium, xlii, 136^f, 392; xliv, 69^f; xlv, 210. ---- Missouriense, xliv, 69^f; xlv, 210. ---- Origonense, xlii, 136^f; xliv, 79. _Osborn, M. W._ and _N. S._, on a vibrating dam, xliv, 366. _Osler, F._, on indications of his anemometer, xxxviii, 103. Osmelite, xv, 388. Osmium, atomic weight and compounds of, _E. Fremy_, xlix, 199. ----, method of obtaining, from the platinum residue, _F. Wöhler_, xxvi, 371. ----, means of obtaining pure, _E. Fremy_, xlviii, 185. Ossification of the vitreous humor, xvii, 186. Ostræa edulis, remarks on, xxxii, 241. ----, see farther under ZOOLOGY, _Mollusca_. Ostrich toes, xxxv, 312.