Polynomials, involution of, _W. J. Lewis_, xlii, 239. Polyps, a group of, v, 46. Polytechnic Institute of Vienna, x, 379. ---- Society of Paris, xxiv, 191. Polythalamia, American, xli, 400.^f ----, fossil, in the United States, _J. W. Bailey_, xlviii, 102, 340.^f ----, ----, from Petersburg, Va., _J. W. Bailey_, xlv, 313. ----, ----, from the Upper Mississippi, _J. W. Bailey_, xli, 400.^f _Pomeroy, S. W._, remarks on the coal formation of Pennsylvania, xxi, 343. Pompeii, how covered, iii, 374. ----, excavation of, iv, 384. Pompton Mountains, N. J., rocks of, v, 241. Pond, a fermenting, v, 199. _Ponton, M._, on paper for photography, xxxvii, 361. Poor, education of, iii, 379. Popocatepetl, ascent of, xxviii, 220. Population of France, xv, 397. ---- of Glasgow, proportion of males to females, xxviii, 80. ---- of Great Britain, xxiv, 211. ---- of Manchester, England, xxviii, 80. ---- of Prussia, ix, 184. ---- of Russia, iv, 389. ---- and religion of Russia, xv, 397. ---- of Sweden, in 1816, 17, 18, ii, 347. ---- of the United States at the earliest census, xxxiii, 278. ---- ----, rate of increase since first census, xxxiii, 278, 279. ---- of New York city, in 1826, x, 398. Populine, xix, 380. Porcelain and porcelain clays, i, 57. ---- and earthenware, on the art, xxvi, 233^f; --history of, 233; Egyptian, 234; Roman, 234; Phenicia, 235; Indian mounds, 237; Chinese, 237; European, 238; Wedgewood ware, 242; kinds of, 259; materials used for, 245; processes, 249; mode of glazing, 254. ----, mode of coloring, iii, 217; xxvi, 256. ----, enamel for, v, 189. ----, manufactory at Philadelphia, xiv, 198; xviii, 384. ----, difference between the English, and that of the continent, xxxiii, 407. ---- clay, from Granby, Ct., xviii, 199. ---- ----, of Pennsylvania and Delaware, xviii, 384. ---- ----, in Maryland, xxvii, 19. Porosity of glass and siliceous bodies, vii, 192. Porphyry of the Chinese frontier, xvii, 32. ---- in Nova Scotia, xv, 203, 213. ---- of Peru, xvii, 57. Portable gas, xv, 189. ---- ---- lamp, iii, 371. _Porter, A. L._, edition of Gray's Operative Chemist, by, noticed, xix, 362. _Porter, J._, floral calendar of Plainfield, Mass., 1818, i, 254. ----, ---- ----, ibid, for 1819; iii, 273. ----, on snow crystals, ii, 339. ----, minerals of Plainfield, v, 270. ----, catalogue of minerals, vi, 246; vii, 58, 252; viii, 233; x, 18. ----, notice of a rocking stone, ix, 27.^f ----, on the American Antiquarian Society, xviii, 136. ----, on the garden of Fromont, xx, 83. ----, Roxbury rocking stone, vii, 59.^f _Porter, R. K._, travels in Persia, xxxvii, 347.