Easy electrical experiments and how to make them; (1918)
Dickinson, Leonard Perley, 1874- [from old catalog] · Chicago, F. J. Drake & co · leaf 133
, and then grinding theends to a sharp point. Insert the needle through the hole inthe piece of watch spring, and fasten the latter in the center of1the needle by two small pieces of wood, circular in shape, whichslip tightly on to the needle, and clamp the piece of watch springtightly. A little… … To the magnetic needle thus mounted a pointer 3 incheslong is to be attached at right angles to the needle. Thebest material of which to make this pointer is a firm, hardStraw taken from an ordinary broom. Straighten it by rub-bing between the fingers, bore a very small hole in one of thewooden…
Electric apparatus and appliances · Electricity
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
