Formic acid, artificial, vii, 197. ---- ----, on the production of, xix, 374. ---- ----, ----, _M. Döbereiner_, xxviii, 126. ---- ----, ----, _Göbel's_ observations on, xxviii, 127. ---- ----, utility of, and theory of its formation, _J. P. Emmet_, xxxii, 140. _Forry, S._, on the climate of the U. States, and general distribution of heat over the globe, xlvii, 18^f, 221. ----, notice of a work on the climate of the U. States, by, xliv, 193. _Forshey, C. G._, Indian mounds and relics near Natchez, xl, 376. ----, ---- ---- in Louisiana, xlix, 38.^f ----, on the meteors of April, 1841, xlii, 397. Forts around Boston, _J. Finch_, viii, 338. Fort Lawrence, account of, _S. P. Hildreth_, xxxi, 57. ---- Macintosh, notice of, xxxi, 19. ---- Taylor, xxxv, 52. ---- Winnebago, geology of region about, _D. Ruggles_, xxx, 1.^f Fortifications, ancient Indian, in Missouri, iii, 37. ----, ---- ----, _S. Taylor_, xliv, 35.^f ----, ---- ----, see farther under _Mounds_. Fossils, means of copying by a galvanic deposit, xlii, 327. ----, use of, in geology, _A. Brongniart_, viii, 213. ----, observations, on ibid, _J. E. Doornik_, xv, 90. Fossil fish, see _Fish_ and also under _Zoology_. ---- footprints, see _Footprints_. ---- vertebral remains in Connecticut valley sandstone, _E. Hitchcock_, xxix, 330. ---- trilobites, see under _Trilobites_. ---- rainmarks, see _Rainmarks_. ---- human bones in Upper Saxony, v, 171. ---- ---- ---- in Guadaloupe, skull, xxxii, 361. ---- ---- ---- in South America, xliv, 277.