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
VOLUME I
700 THINGS FOR BOYS TO DO
WITH 800 ILLUSTRATIONS
1913, BY H. H. WINDSOR CHICAGO
POPULAR MECHANICS CO. PUBLISHERS
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