; a 224 Atwericat. [SEPTEMBER 30, 1893. Scientific … of a diaphragm, made of a plate of iron It will turn like a screw $6.00 Parsons Horological Institute. or steel, or other material capable of in- into wood when driven Tlearnthe Watet Trade ductive action; the fifth, of a permanent It is with a hammer, and TO cheaper than will not break the magnet…
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