crosshead runs in guides made from a piece of gas pipe with the
sides cut out and threads cut on both ends. One end is screwed
into a rim turned on the cylinder head and the other is fitted
into an oblong plate. Both ends of this plate were drilled and
tapped to receive 1-1/2-in. pipe.

The main frame consists of one 1-1/2in. pipe 10 in. long and one
made up from two pieces of pipe and a cross to make the whole
length 10 in. These pipes were then screwed into pipe flanges that
served as a base. The open part of the cross was babbitted to
receive the main shaft. The end of the shaft has a pillow block to
take a part of the strain from the main bearing. The eccentric is
constructed of washers. While this engine does not give much
power, it is easily built, inexpensive, and anyone with a little
mechanical ability can make one by closely following out the
construction as shown in the illustration.
--Contributed by W. H. Kutscher, Springfield, Ill.

** How to Make a Copper Bowl [185]

To make a copper bowl, such as is shown in the illustration,
secure a piece of No. 21 gauge sheet copper of a size sufficient
to make a circular disk 6-1/2 in. in diameter.

Cut the copper to the circular form and size just mentioned, and
file the edge so that it will be smooth and free from sharp
places. With a pencil compass put on a series of concentric rings
about 1/2 in. apart. These are to aid the eye in beating the bowl
to form.

The tools are simple and can be made easily. First make a
round-nosed mallet of some hard wood, which should have a diameter
of about 1-1/4 in, across the head. If nothing better is at hand,
saw off a section of a broom handle, round one end and insert a
handle into a hole bored in its middle. Next take a block of wood,
about 3 by 3 by 6 in., and make in one end a hollow, about 2 in.
across and 1/2 in. deep. Fasten the block solidly, as in a vise,
and while holding the copper on the hollowed end of the block,
beat with the mallet along the concentric rings.

Begin at the center and work along the rings--giving the copper a
circular movement as the beating proceeds--out toward the rim.
Continue the circular movement and work from the rim back toward
the center. This operation is to be continued until the bowl has
the shape desired, when the bottom is flattened by placing the
bowl, bottom side up, on a flat surface and beating the raised
part flat. Beating copper tends to harden it and, if continued t