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 318
which tends to draw thewires within the coil. The action is strongest whenthe helix surrounds that end of the tube from whichthey are projected. 496. Double Helix and Vibrating Electro-tome. — The instrument represented in Fig. 182 isone of the most convenient for the medical applica-tion of… … bands. The helices are insulated from each other,but are not separable. A bundle of iron wires isshown in the cut, within the inner helix. This can26 302 DAVISS MANUAL. be removed at pleasure. The vibrating electrotome,which is fixed on the stand, is of the same construc-tion as that represented in…
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