Silver, atomic weight of, xlvii, 189. ----, effect of terrestrial magnetism on the precipitation of, xvi, 262. ----, Gregory's method of obtaining, from the chloride, xlvi, 201. ----, reduction of the chloride of, xxviii, 145. ----, production of the discolored chloride of, _Cavalier_, xx, 193; xxi, 369. ----, chloride of, on the change of color, xx, 193; xxi, 369. ----, fulminating, accidents from, i, 169; xxii, 185. ----, ----, xviii, 335. ----, ----, of Berthollet, xviii, 155. ----, ----, _Mitscherlich's_ mode of preparation, xix, 379. ----, on some of the substances which may be used in forming a metallic mirror by the precipitation of the oxide of, xlix, 398. ----, hyperoxide of, xlix, 194, 391. ----, purple precipitate of, xxii, 198. ----, German, made by _Frick_, xiii, 172. ----, imitation, xxiii, 195. ----, preparation of pure nitrate of, v, 348; xxiv, 370. ----, nitrate of, reduced by remaining in a pasteboard box, xviii, 400. ----, ----, pure, not blackened by sun's rays, xxxv, 298. ----, native, at Huntington, Conn., vi, 230. ----, ----, in New Jersey, v, 401. ----, ----, of Davidson Co., N. C., xli, 183, 349. ----, ----, in Michigan, Lake Superior, xli, 185; xlix, 81. ---- of Lane's mine, analysis of, _W. W. Mather_, xxvii, 256. ----, in the Southampton lead mines, Mass., xxii, 63. ----, fruitless search for, in Ohio, xxv, 224. ---- ores, reduction of, _W. W. Mather_, xxiv, 218. ----, yield of Russian mines of, xxi, 372. ---- mines of Nertchinsk, xvii, 34. ---- ---- of the Hartz, xix, 113. ---- ---- of Peru and Chili, xvii, 43. ---- ----, ----, Pasco, S. America, sketch of, _De Rivero_, xvii, 43.^f ---- ---- ----, Tarapaca, xliv, 8. ---- ---- of Mexico and South America, xxiv, 213, 226. ---- ---- of Davidson Co., North Carolina, xli, 183, 348. ----, sulphuret of, in New York, i, 237. ---- ore, red, analysis of, v, 377. ---- paper, mode of imitating, xix, 189. Silvering copper, xxiii, 386. ---- glass, Drayton's method, xlix, 198. ---- iron, xxx, 169. _Simond, L._, notice of, xxiii, 371. Sines and cosines of the sum and difference of two arcs, formulæ for, _T. Strong_, i, 424.^f ----, rational expression for, _D. Gould_, xxii, 392. Singapore, climate and productions of, _J. S. Travelli_, xliv, 151. Siren, notice of genus and species, _D. H. Barnes_, xi, 281. Sismondine, analysis and description of, _A. Delesse_, xlvii, 217. Sium tricuspidatum, xi, 175. Sivatherium, xxxi, 170; xxxiii, 104. Size for artists, receipt for, xxi, 168. ----, new, for the chain of woven cloth, xxii, 366. ---- for cotton or linen, preparation of, xxii, 367. Skeleton, human, of Guadaloupe, _J. Moultrie_, xxxii, 361. ----, ----, ancient in Ohio, ii, 242. ----, preservation of, xix, 57. _Skene, J._, on the emigration of a colony of caterpillars, ix, 284.^f ----, graduation of thermometers, xii, 397. _Skidmore, T._, formation of flexible elastic lubes, v, 153.