Book 3 — A Revolving Window Display

A jeweler attracted passers-by and not a few customers by placing a revolving display in his window which was kept in motion by means of the arrangement shown in the sketch. A 10-in. cut-glass bowl was placed, upside down, near the front of the show window. An inverted tumbler was set upon it and a small tin box was pivoted on the tumbler by means of a needle soldered inside of it. Six arms of wire were soldered to the box, and watches were suspended from them. The carefully balanced frame revolved easily on the point of the needle. It was kept in motion by the draft from a fan hidden behind a mirror.—H. S. Hart, Shreveport, La.