Davis's manual of magnetism : including galvanism, magnetism, electro-magnetism, electro-dynamics, magneto-electricity, and thermo-electricity (1854)
Davis, Daniel · Boston : Palmer and Hall · leaf 193
current traverses the lower half, also producingrotation. 282. In Sillimans Journal for March, 1847, will befound a figure and description of a similar instrument,contrived by Dr. Page, in which no mercurial con-nections are used. The bar is sustained withoutvisible support, as in Fig. 115, and the… … INCLINED B. EVOLVING BAR. 177