Magnetize an ordinary knitting needle, A, and push it through a cork, B, and place the cork exactly in the middle of the needle. Thrust a pin, C, through the cork at right angles to the needle and stick two sharpened matches in the sides of the cork so that they will project downward as shown.
The whole arrangement is balanced on a thimble with balls of wax stuck on the heads of the matches.
If the needle is not horizontal, pull it through the cork to one side or the other, or change the wax balls. The whole device is placed in a glass berry dish and covered with a pane of glass.
Magnetized Needle Revolving on a Pin
Excerpt from the book:
THE BOY MECHANIC
700 THINGS FOR BOYS TO DO
WITH 800 ILLUSTRATIONS
1913, BY H. H. WINDSOR CHICAGO
POPULAR MECHANICS CO. PUBLISHERS