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Popular Mechanics Co.

"The Boy Mechanic: Volume 1 700 Things for Boys to Do"

The armature, B, is pivoted in the center by means of a
small piece of wire and has an indicator or hand, C, which moves
to either right or left, depending on which half of the magnet is
magnetized. If the back armature, D, of the magnet is removed the
moving armature will work better, as this will prevent the
magnetism from acting on both ends of the armature.
The wiring diagram, Fig. 2, shows how the connections are to be
made. If the pushbutton A is closed; the bell will ring and the
pointer will point at 1,
[Illustration: Annuciator and Wiring Diagram]
while the closing of the push-button B will ring the bell and move
the pointer to 2.
--Contributed by H. S. Bott, Beverly, N. J.

** How to Make a Box Kite [58]
As some of the readers of Amateur Mechanics may desire to build a
box kite, a simple method of constructing one of the modern type
is given in detail as follows: The sticks should be made of
straight grained wood, which may be either spruce, basswood or
white pine. The longitudinal corner spines, A A, should be 3/8 in.
square by 42 in. long, and the four diagonal struts, B, should be
1/4 in.


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