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 236
rinciple as in theRevolving Spur-Wheel(§ 180), an electro-magnettaking the place of the steelmagnet. There are twowheels ; of these, the up-per and larger one is partlysupported by springs, itscircumference resting onthat of the smaller wheel.The current traverses in succession the coil of… … 220 DAVISS MAN UAL . wheel is not merely carried round by the other, butthose parts of both which are conveying the ^Airrenttend to move away from between the poles in thesame direction, causing the two wheels to revolve inopposite directions. 350. Revolving Wheels.—A better form isshown in Fig.…
