er assembling, by rigging
up a temporary toolrest in front of the headstock.

The tail stock (Fig. 7) is fastened to the bed in the same manner
as the headstock, except that thumb nuts are used on the carriage
bolts, thus allowing the tail stock to be shifted when necessary.
The mechanism of the center holder is obtained by using a 1/2-in.

[Illustration: FIG.7 Details of Tailstock]

pipe, A, and a 1/2-in. lock nut, B, embedded in the wood. I found
that a wooden tool-rest was not satisfactory, so I had to buy one,
but they are inexpensive and much handier than homemade tool rest.
--Contributed by Donald Reeves, Oak Park, Ill.

** To Use Old Battery Zincs [87]

When the lower half of a battery zinc becomes eaten away the
remaining part can be used again by suspending it from a wire as
shown in the cut. Be sure and have a good connection at the zinc
binding post and cover that with melted paraffin. This prevents
corrosion, which would otherwise occur from the action of the sal
ammoniac or other chemical. The wire may be held at the top by
twisting it around a piece

[Illustration: Showing Zinc Suspended]

of wood or by driving a peg through the hole in the porcelain
insulator.
--Contributed by Louis Lauderbach, Newark, N.J.

** Callers' Approach Alarm [87]

This alarm rings so that callers approaching the door may be seen
before they ring the bell and one can exercise his pleasure about
admitting them.

If one has a wooden walk, the alarm is easy to fix up. Take up
about 5 ft. of the walk and nail it together so as to make a
trapdoor that will work easily. Place a small spring under one end
to hold it up about 1/4 in. (A, Fig. 2). Nail a strip of tin along
the under side of the trap near the spring and fasten another
strip on the baseboard, so that they will not touch, save when a
weight is on the trap. Connect up an electric bell, putting the
batteries and bell anywhere desired, and using rubber-covered

[Illustration: Alarm Rings When Caller Approaches]

wire outside the house, and the alarm is complete.

When a person approaching the house steps on the trap, the bell
will ring and those in the house can see who it is before the door
bell rings.
--Contributed by R. S. Jackson, Minneapolis, Minn.

** Easy Method of Electroplating [88]

Before proceeding to electroplate with copper, silver or other
metal, clean the articles thoroughly, as the least spot of grease
or dirt will prevent

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