_Maclure, W._, on different systems of education, ix, 160, 163. ----, on the Pestalozzian system of, ix, 163; x, 145. ----, geological arrangement, outlines of, i, 209. ----, systematic arrangement of rocks and their probable origin, vii, 261. ----, geological systems, geological maps, and chatoyant feldspar, ix, 253. ----, ---- changes in N. America, conjectures on, east of the Stoney mountains, vi, 98. ----, ---- remarks on Mexico, xx, 406. ----, igneous theory of the earth, remarks on, xv, 384; xvi, 351. ----, on Mosaic geology, ix, 157. ----, passage to Mexico of, xv, 400. ----, memoir of, _S. G. Morton_, xlvii, 1.^f ----, list of works of, xlvii, 16. Maclurite, description of, v, 246. ----, analysis of, _H. Seybert_, v, 336. ----, identical with chondrodite, v, 366. ----, in New Jersey, v, 343. Madeira, notice of, xxiv, 238. ----, wines of, xxiv, 240. Mæcenas, bust of, xxxiv, 51. _Maerenhaut, J. A._, on Otaheite, xxix, 283. _Magendie, F._, on the mechanism of absorption in animals, iii, 288. ----, on prussic acid, ii, 81. Magic, natural, remarks on, xxxiii, 258. Magnesia, effect of, on soil, xli, 159. ----, solubility of, v, 378. ----, in compact limestones, large proportion of, _R. E. Rogers_, xli, 171. ----, carbonate of, of Staten Island, N. Y., i, 142; v, 266. ----, ----, in Pennsylvania, i, 236; xiv, 18. ----, hydrate of, description and analysis of, iv, 245. ----, ----, in New Jersey, i, 55; iv, 17; v, 267. ----, ----, in Hoboken, i, 54; iv, 17; vii, 370. ----, ----, from Shetland, vii, 365. ----, nitrate of, i, 133. ----, sulphate of, i, 133; ii, 375; xv, 241. ----, ----, native in New York State, xv, 241. ---- and soda, sulphate of, xlviii, 189. Magnesian carbonate of lime, in N. York, analyses of, _L. C. Beck_, xlvi, 34. ---- hydrate of silica. Harford Co., Md., _P. T. Tyson_, xviii, 79. ---- ---- ---- identity of, with Deweylite, _C. U. Shepard_, xviii, 81. ---- pseudomorphs, and metamorphic changes, xlviii, 89. Magnesite, hard, from Baumgarten, Silesia, vii, 368. ----, in N. York, v, 267; xlvi, 34. ----, in Maryland, xiv, 12. ----, in Pennsylvania, xiv, 9, 10. Magnesium, notice of, xix, 197, 379; xxvii, 196. ----, obtained by _W. W. Mather_, xx, 408.