Elementary lessons in electricity and magnetism (1906)
Thompson, Silvanus P. (Silvanus Phillips), 1851-1916, Schwetzky, Otto H. L. [from old catalog] · Chicago, Thompson & Thomas · leaf 69
, supported on insulating holders,are two horizontal metal combs, joined to two metal rodsterminated with brass balls, ni^ «, which in this form of machinemerely constitute a discharging apparatus and are not concernedin the action of the machine. In some forms of Holtz machinethere is no diagonal… … will charge itself. To work the machine a small initial chargemust be given by an electrophoms, or by a rubbed glass rod, toone of the two armatures. The disc is then rapidly rotated ; and it is found thatafter a few turnsthe exertion requiredto keep up the ro-tation increases-greatly: at the…
Electricity · Magnetism
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