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 195
e contact with the vertical conducting wire,which enters a short distance only within it. Anivory ring, surrounding the wire, insulates the littlearm by which the bar is sustained in its inclinedposition, so that the current does not traverse theupper part of the bar. When enough of the mercuryis… … AXIAL REVOLVING CIRCLE. 179 286. A short iron rod, placed in the glass tubeinstead of the inclined bar, floats in the mercury.vVhen the current is passed through the verticalwire, the rod is drawn down into the tube, and re-volves around the wire and on its axis. By cov-ering the rod with…
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