_Bowring, J._, on the boracic acid lagoons of Tuscany, xxxvii, 270. _Boyé, M. H._, production of a perchloric ether, xl, 50. ----, on perchloric ether, xlii, 63. _Brace, J. P._, list of plants growing in Litchfield Co., Conn., iv, 69, 292. ----, on the minerals of Litchfield Co., Ct., i, 351. ----, on the Phalæna devastata or cut-worm, i, 154. _Braconnot_, on xiloidine, xxviii, 131. _Brady, Samuel_, legend of, xxxi, 43. Brady's Hill, legend of, xxxi, 20. Brain of idiots, defective, xxxiv, 31. _Brandes, H. W._, notice of, xxviii, 97. ----, observations on shooting stars, xv, 168; xxviii, 97; xxxiii, 361; xxxv, 231, 361. Brandy from potatoes, _Siemen's_ process for making, ix, 386. _Braun, A._, Charæ of North America, xlvi, 92. ----, on North American Equiseta, xlvi, 81. Brazil, number of known plants in, xv, 390. Bread, on alcohol in, xxiii, 194; xxvi, 211. ----, use of sulphate of copper and other saline materials in making, _M. Kuhlmann_, xx, 269. Breast wheels, _A. B. Quinby_, xi, 333. Breathing, voluntary, v, 203. Breccia, cemented by hematitic iron, viii, 18. ----, quartzose, in western Massachusetts, viii, 18. Breislakite, xi, 250. _Breithaupt's_ specific gravities of minerals, table of, xxxi, 268. _Bremicker's_ comet, xl, 207. Brevicite, a new mineral species, xxx, 178. _Brewster, D._, on the distribution of the coloring matter and the optical properties of the Brazilian topaz, vii, 364. ----, a new fluid in minerals, vii, 186. ----, new structure in the diamond, xxxiv, 37. ----, monochromatic lamp, vii, 363. ----, double refraction resulting from pressure, xxi, 296. ----, cause of double refraction in crystals, xxi, 299. ----, on the polarization of light by reflection, xxii, 277.^f ----, on the action of second surfaces of transparent plates upon light, xxiii, 28.^f ----, laws of the polarization of light by refraction, xxiii, 225.^f ----, a new properly of light, xxxiv, 20. ----, a new kind of polarity in homogeneous light, xxxv, 292. ----, new discoveries with the spectrum, xliv, 163, 164. ----, dichroism of some palladio-chlorides, xliv, 165. ----, on the cause of muscæ volitantes, xl, 333. ----, on the decomposition of glass, and on the polarization of decomposed glass, xl, 324, 325. ----, on the line of visible direction, along the axis of vision, xl, 334. ----, cause of increase of color when objects are seen with the head inverted, xl, 343. ----, action of gaseous and other media on the solar spectrum, xlii, 157. _Brewster's_ (_Gilbert_) frame for spinning wool, notice of, x, 130. Brewsterite, xx, 198. Bricks of the ancients, xxvi, 234. ---- made near Jamaica, N. Y., xxxvi, 21. ---- made by a press, vi, 396. ----, use of anthracite in the making of, _W. Meade_, xviii, 118. ----, fire, made at Bennington, Vt., xxxii, 195; xxxiii, 202. Bridge-building, _Town's_ new mode of, iii, 158^f; xxxviii, 276.^f