Simple Arc Light Works From Battery, Uses Pencil Leads for Electrodes (Jan, 1932)

Simple Arc Light Works From Battery, Uses Pencil Leads for Electrodes

TO MAKE an arc light of the simplest type only a few scrap parts are necessary. The sparking points of the arc are made from two pencil leads, the lower one being mounted in a plaster of paris cast, while the upper one is held by an adjustable arm, as illustrated in the accompanying drawing. This arm is supported by an upright and is adjusted with the weight and stop block as shown. The upper and lower carbons of the arc are hooked to a six-volt storage battery, which can be cut out by a small knife switch inserted in the circuit.

For best lighting effects a concave metal reflector polished to focus rays should be placed behind the arc.