The accompanying sketch shows the construction of a handy device for testing miniature electric lights. The base is made to take in an electric flash lamp battery. Two strips of brass, C and D, are connected to the battery. The lamp is tested by putting the metal end on the lower brass strip and the side against the upper one. A great number of lamps can be tested in a short time by means of this device.

Contributed by Abner B. Shaw, North Dartmouth, Mass.

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