— - —, —, theoretical considerations, J. Henry, xli, 135.f
[Electro-magnet,] Henry's large, xix, 408.f
— - —, made for the Laboratory of Yale College, xx, 200.
— - —, a variety of, proposed, J. Humbert, xxxviii, 205.
— - —, Mr. Ganby's, xxix, 354.
— - —, C. G. Page's, xxxv, 253.f
— - —, see farther under [Electro-magnetic] apparatus.
[Electro-magnetic] apparatus, J. H. Abbot, xl, 104.f
— - — —, P. Barlow, v, 396.f
— - — —, A. W. Campbell's engine, xxxv, 343.