Skins, preservation of, xi, 397. ----, ----, see farther under _Preservation_. Skugisan, xxvi, 388. Skull found in a tree, iv, 377. ----, of Guadaloupe human skeleton, _J. Moultrie_, xxxii, 361. Skulls, singular variety of, from Peru and Bolivia, xxviii, 78. ----, American, observations on, _J. C. Warren_, xxxiv, 47. ----, ----, _S. G. Morton_ on, xxxviii, 341.^f ----, _S. G. Morton's_ collection of, xxi, 197. ----, proposed new work on, by _S. G. Morton_, xxxii, 207. ----, ---- ----, reviewed, xxxviii, 341.^f Skunk, American, iv, 391. Sky, on the cause of the blue appearance of, _B. Hallowell_, xv, 360. ----, ibid, xxvi, 65. Slates, artificial, in Russia, vii, 191. Slate, roof, in western Massachusetts, viii, 19, 20. ----, ----, in Worcester Co., Mass., xxii, 34. ----, fused to hornstone, xxxiv, 73. Sleep of plants, xxii, 375. Slide of Alpnach, xxiv, 124. ---- in Essex Mountains, _W. C. Redfield_, xxxiii, 313. ---- from Mount Pilatus to the Lake of Lucerne, iii, 368. ---- and avalanches in the White and Green Mountains, xv, 217. Small pox, nature of the virus of, xix, 389. ---- ----, _F. Pascalis's_ theory of its origin, x, 208. ---- ----, on the increase, xxxviii, 134. ---- ----, power of new virus, xxxviii, 134. Smilax grandifolia, xlv, 171. _Smith, Al._, Connecticut valley, water courses and geology of, xxii, 205.^f ----, ---- ----, terraces of, xxii, 214. ----, ---- ----, ancient lakes, xxii, 216. ----, ---- ----, greenstone, xxii, 224. _Smith, Az._, electricity in machines, xxxix, 134. ----, ruins of Nineveh, xlix, 113. _Smith, D. B._, Principle of Chemistry, by, noticed, xlvii, 414. _Smith, E. D._, effects of earthquakes of 1811-12, i, 93. ----, Warm springs in Buncombe Co., North Carolina, iii, 117. ----, analysis of the Harrodsburg salt, i, 403. ----, application of medico-chemistry to calculous affections, iii, 300. _Smith, F. L._, on the gold deposits of a portion of North Carolina, xxxii, 130. _Smith, H._, letter to B. Silliman, xxxv, 336. _Smith, H. L._, on some nebulæ, xl, 37. ----, discovery of a comet, xlvii, 419. _Smith, J._, on Atlantic steam navigation, xxxv, 160, 332; xxxvi, 133. _Smith, J. D._, analyses of guano, xlviii, 183.