Estimated Date: 1873
Name: Grigg’s Electro Magnetic Machine
Description: 10“x 4.5” stand supports a 10” long wood covered conical coil which tapers from 2.75” to 1”. There is an ivory knob on the end of the rod which enters the coil from the narrow end to adjuct the voltage. A U-shaped transformer with red painted wiring is on the base as are 5 brass contact posts each 2.25”. In addition, there are two wood handled sponges (6” with handle) for application. The whole of mahogany.
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