Gypsum, action of, as a manure, xxvi, 181. ----, experiments on the solidification of, _J. P. Emmet_, xxiii, 209. ----, fertilizing properties of, xxii, 350. ----, origin of, _L. Vanuxem_, xii, 92. ----, curved, mammoth cave, Ky., xlii, 206.^f ---- of the basin of mines, Nova Scotia, xv, 146. ----, localities of, in New York, i, 243; iv, 36; v, 39, 40; xvi, 377; xxxvi, 38. ----, ----, in Maryland, xxvii, 8. ----, ----, in Ohio, iv, 51, 52; v, 39; vii, 48; xvi, 158. ----, ----, in Canada, viii, 71. ----, ----, in Michigan, vii, 47. ----, ----, in Virginia, i, 62; iv, 52. ----, ----, Prince Regent's Inlet, xvii, 10. ----, ----, in Nova Scotia, xiv, 229; xv, 146. ----, ----, in the Hartz, xix, 111. ----, ----, in Sicily, viii, 204. ----, ----, in Africa, iv, 33. ---- and accompanying marine limestones, in Nova Scotia, age and position of, _C. Lyell_, xlv, 356. Gyropodium coccineum, ix, 56.^f H. Hæmatoxylin, _O. L. Erdman_, xliv, 357. Hail, formation of, xix, 396. Hail storms, cause of, in warm weather, _B. Hallowell_, xv, 361. ---- ----, phenomena and causes of, _D. Olmsted_, xviii, 1.^f ---- ----, reply to _A. T. Christie_ on, by _D. Olmsted_, xx, 373. ---- ----, _A. T. Christie's_ views on, xx, 373. ---- ----, _A. Jones_, xxiii, 35.^f ----, ----, remarks on, _W. C. Redfield_, xxxiii, 55. ----, ---- in Louisiana, _W. M. Carpenter_, xxvii, 171. ----, ----, rods a protection against, x, 196. Hail-rods, in France, x, 196; xii, 398. ---- ----, ----, efficacy of, xiv, 37. _Haile, A. B._, observations on the magnetic disturbance during an Aurora, Nov., 1837, xxxiv, 270. Hailstones, structure of, xxiii, 36.^f ---- at Clermont, France, large, xxxi, 191. _Haldeman, S. S._, on the Melanians of Lamarck, xli, 21; xlii, 216. ----, notice of the zoological writings of the late _C. S. Rafinesque_, xlii, 280. ----, species of mollusca common to Europe and America, xlvii, 412. _Hale, M._, geological notice of Troy, iii, 72. _Hall, F._, notice of, xlvii, 139. ----, notes on a tour in France, Italy and Elba, xxxii, 74. ----, on some minerals from Palestine, ix, 337. ----, notice of oriental minerals, xxxiii, 249. ----, ores of iron and manganese in Vermont, iii, 57. ----, waterfall, in the Green Mts., and an excavation in the rocks, vi, 252. _Hall, James_, on the crinoidea, xlv, 349. ----, fossils of U. States, general remarks on the distribution of, xlv, 157; xlvii, 117. ----, Paradoxides, species of, xxxiii, 139.^f ----, ripple marks and casts of furrows, xlv, 148. ----, sections at Portage, N. Y., xlv, 329. ----, shells, microscopic, from a marl slate, Cincinnati, xlviii, 292. _Hall, J._, Western States, general account of geology of, xlii, 51. _Hall, John_, on the staining of wood, and on medical electricity, iii, 166.