Prussic acid, _F. Magendie_ on, ii, 81. ---- ----, memoir on, _B. L. Oliver_, iii, 182. ---- ----, ----, _Orfila_, xviii, 157. ---- ----, effect of muriatic and sulphuric acids on, xviii, 146. ---- ----, extraordinary production of, _A. A. Hayes_, xviii, 201. ---- ----, preservation of, xvi, 260. ---- ----, apparatus for the evolution of, _R. Hare_, xxix, 244.^f ---- ----, impurities of, xix, 70. ---- ----, cases in which administered, iii, 187. ---- ----, efficacy in asthma, vi, 366. ---- ----, action of, on a horse, xii, 385. ---- ----, effects on vegetation, x, 190. ---- ----, chlorine an antidote for, xvii, 174; xxi, 157. Pseudomorphine, a new vegetable extract, xxx, 179. Pseudomorphism, observations on, _J. D. Dana_, xlviii, 81, 397. Pseudomorphous minerals, account of, in a review of _J. R. Blum's_ treatise, xlviii, 66. ---- (crystallized) steatite, in Massachusetts, _C. Dewey_, iv, 274; v, 249; vi, 333; viii, 51. ---- steatite, having the form of quartz, scapolite and spinel, xxi, 320. ---- steatitic hornblende, analysis of, _L. C. Beck_, xlvi, 35. ---- quartz, at Southampton lead mine, vi, 214; ix, 249. ---- ----, in Pennsylvania, x, 223. ---- granite, vii, 22.^f Pseudomorphs, siliceous, in Hampshire Co., Mass., xii, 256. Pseudo-volcanoes of the Upper Missouri, xlv, 154. Psora, use of chloride of lime in, xvi, 395. Pudding stone of Mount Toby, Mass., vi, 8, 69. Pulkova Observatory, xlvii, 88. Pulmonary consumption, work on, _S. G. Morton_, noticed, xxv, 424. Pultowa, monument of, iii, 379. Pumice, floating, xx, 161. ---- at the Azores, iv, 259. ---- of the Mississippi, iii, 247. ---- of the Missouri and Mississippi rivers, due to pseudo-volcanoes, _J. N. Nicollet_, xlv, 154. Pump, by steam, xvi, 181. ----, air, see _Air pump_. Purple of Cassius, ii, 350; xx, 192; xxviii, 145; xlviii, 192. _Pursh, F._, notice of the herbarium of, xl, 11. ----, botanical excursions of, xlii, 10. ----, notice of, ix, 269. Putnam's rock, v, 37. Putnam Hill, section of, xxix, 30.^f Putrefaction, animal, xviii, 397. ---- of stagnant water, prevented by animal charcoal, x, 189. _Puvis_, essay on lime as a manure, xxx, 138. Pyrargillite, analysis and description of, _Nordenskiöld_, xxvi, 387. Pyrenees, geological notice of, ix, 23. ----, botany of, remarks on, xiv, 377.