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 305
ttached the screw-cups C and D. A bundle ofannealed iron wires, of which the ends are seen inthe cut, can be removed from the inner helix whendesired. 468. In Fig. 180, the different parts of the instru-ment are shown separately. The exterior helix, a, isremoved from the inner coil, 6, which is… … o- o est shocks, the bundle should fill the hollow of thehelix. The other parts are lettered in correspond-ence with the last figure. 469. The bundle of iron wires being withdrawn,let a wire connected with one pole of a galvanicbattery be fixed in the cup A, and the other batterywire be drawn over…
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