The steel core should be wound with
about 250 ft. of No. 36 insulated wire, the ends of which should
be soldered to a piece of
[Illustration: Telephone Receiver]
lamp cord, passed through a hole in the bottom of the can and
knotted inside to prevent pulling out.
A disk of thin sheet-iron, such as is used by photographers for
tintypes (Ferrotype), should be cut to the diameter of the can,
taking care not to bend the iron. The magnet should then be placed
in the bottom of the can in an upright position and enough of a
melted mixture of beeswax and resin poured in to hold it in
position.
While the wax is still in a plastic condition the magnet should be
located centrally and adjusted so that the end will be 1/16 in. or
less below the level of the top of the copper ring.
After the wax has hardened the disk is slipped in and fastened
tightly by a ring of solder when the instrument is ready for use.
** How to Bind Magazines [56]
An easy way to bind Popular Mechanics in volumes of six months
each is to arrange the magazines in order and tie them securely
both ways with a strong cord.
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