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Popular Mechanics Co.

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

It is the simplest thing in the
world for a sneak thief to slip a thin knife between the
door-casing and the strip, push back the bolt, and walk in.
Fortunately, it is equally easy to block that trick. Take a narrow
piece of tin 3 or 4 in. long, bend it at right angles throughout
its length, and tack it firmly in the angle between the casing and
strip, so as to make it impossible to reach the bolt without
tearing off the strip.
Another way is to drive nails through the strip at intervals of
half an inch, enough to protect the bolt from being meddled with.

** A Controller and Reverse for a Battery Motor [72]
Secure a cigar or starch box and use to make the base, B. Two
wood-base switches, S S, are cut off a little past the center and
fastened to the base with a piece of wood between them. The upper
switch, S, is connected to different equal points on a coil of
wire, W, while the lower switch, S, is connected each point to a
battery, as shown. The reverse switch, R, is made from two brass
or copper strips fastened at the top to the base with screws and
joined together by a piece of hard rubber or wood with a small
handle attached.


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