---- ----, for galvano-ignition apparatus, _R. Hare_, xxxii, 284.^f ---- circle, theory of, _T. Graham_, xxxviii, 117. ---- currents, caloric a cause of, _J. P. Emmet_, xxv, 269. ---- ----, remarks on, xviii, 199.^f ---- ----, and sparks from the horse-shoe magnet, _J. P. Emmet_, xxiv, 78.^f ---- deflagrator, _Hare's_, iii, 105^f; iv, 201; v, 94; vi, 337; vii, 347^f; viii, 99; ix, 181; xl, 48. ---- ----, improved form of, _M. Faraday_, xxxii, 170. ---- experiments by _A. Crosse_, producing crystals, and, as supposed, insects, xxxv, 125.^f ---- ----, by _R. Hare_, viii, 145. ---- ----, with grasshopper's legs, _J. W. Bailey_, xxxi, 292.^f ---- ignition of gunpowder, _R. Hare_, xxxvii, 269. ---- induction, _J. P. Emmet_, xxvi, 23.^f ---- lamp, an improvement in, by _Dr. J. Cutbush_, ii, 332. ---- light, transmission of, through metals of different conducting powers, _J. Thomas_, xxxiv, 205.^f ---- ----, daguerrotype experiment by, _B. Silliman, Jr._ and _W. H. Goode_, xliii, 185. ---- multiplier, see _Galvanometer_. ---- music, production of, _C. G. Page_, xxxii, 396; xxxiii, 118. ---- phenomenon, attending the soldering of water pipes in N. York city, xvii, 194. ---- protection by the contact of heterogeneous metals, xvi, 263. ---- trough, _Watkins's_, xvi, 215. _Galvanism_, anthracite a conductor of, v, 200. ----, charcoal fused by, v, 108, 361; viii, 147, 288; xxxviii, 190. ----, ---- ----, _L. Vanuxem's_ examination of, viii, 292. ----, on colors supposed to be transferred by, through animal substances, _A. Jones_, xxi, 316. ----, _A. Crosse's_ experiments in, see _Crosse_. ----, crystallization of metals by, _G. Bird_, xxxiii, 267. ----, ----, _M. Becquerel_, xvii, 383. ----, crystals and insects, _A. Crosse_, xxxv, 125.^f ----, engravings copied by, _von Kobell_, xlviii, 221.^f ----, engravings and medals by, _T. Spencer_, xl, 157.^f ----, fossils copied by, xlii, 327. ----, gilding by, xli, 402. ----, insects supposed to be produced by, xxxii, 374^f; xxxiii, 272; xxxv, 125^f; xlix, 227. ----, ----, ----, _W. H. Weekes_, xliii, 395. ----, grasshopper's legs, a substitute for frogs, _J. W. Bailey_, xxxi, 292.^f ----, insulation of wires, a mode of, proposed, _A. A. Hayes_, xx, 409. ----, metals precipitated by, structure of, _W. de la Rue_, xlix, 390. ----, minerals changed by, _R. W. Fox_, xxxi, 373. ----, results from heat of, and decomposition, _W. Sturgeon_, xxxix, 29. ----, shocks from the calorimotor, how increased, _C. G. Page_, xxxi, 137.^f ----, size of plates, influence of, in, xxvii, 189. ----, theory of, _Prof. Pfaff_, xix, 178. ----, theory of, _R. Hare_, i, 413.^f ----, theory of, _Schönbein_, xxxviii, 119.