Trebel, George. [from old catalog] · New York, F. Tousey · leaf 40
rated. Insert them in the tube, andcover with dilute sulphuric acid (1 to 20). In the center ofthe coil lay a No. 16 soft iron wire D, and float the whole in avessel of water. The apparatus constitutes a small floatingbattery and electro-magnet. Bring one end of a permanentmagnet, or a short piece… … Remove the iron wire from the floating electromagnet andbring a separate battery wire over and parallel with the helix,as in Figure 6. In this position the two currents flow inplanes at right angles to one another. Immediately the coilturns and tends to take a position at right angles to the…
Electricity
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