nozzle and the blades to
allow for sufficient play, Fig. 3.

The bearings are made of 1/4-in. brass and bolted to the casing,
as shown, with 1/8-in. machine screws and nuts. Two nuts should be
placed on each screw. The pulley is made by sliding a piece of
steel pipe on the engine shaft and fastening it with machine
screws and nuts as shown in Fig. 6. If the shaft is square, lead
should be run into the segments.

The driven shaft should have a long bearing. The pulley on this
shaft is made of pieces of wood nailed together, and its
circumference cut out with a scroll saw. Flanges are screwed to
the pulley and fastened to the shaft as shown in Fig. 7.

The bearings are made of oak blocks lined with heavy tin or sheet
iron for the running surface. Motion is transmitted from the
engine to the large pulley by a thin but very good leather belt.

** Homemade Telegraph Key [21]

A simple and easily constructed telegraph key may be made in the
following manner: Procure a piece of sheet brass, about 1/32 in.
thick, and cut out a strip 3-1/2 in. long by 3/4 in. wide. Bend as
shown in Fig. 1 and drill a hole for the knob in one end and a
hole for a screw in the other. Procure a small wood knob and
fasten it in place with a small screw. Cut a strip of the same
brass 2-3/4 in. long and 5/16 in. wide and bend as shown in Fig.
2. Drill two holes in the feet for screws to fasten it to the
base, and one hole in the top part for a machine screw, and solder
a small nut on the under side of the metal over the hole.

Mount both pieces on a base 4-1/4 by 2-3/4 by 1/4 in., as in Fig.
3, and where

[Illustration: Brass Key on a Wood Base]

the screw of the knob strikes the base when pressed down, put in a
screw or brass-headed tack for a contact. Fasten the parts down
with small brass wood-screws and solder the connections beneath
the base. Binding posts from an old battery cell are used on the
end of the base. The screw on top of the arch is used to adjust
the key for a long or short stroke.
--Contributed by S. V. Cooke, Hamilton, Canada.

** Keeping Food Cool in Camps [21]

Camps and suburban homes located where ice is hard to get can be
provided with a cooling arrangement herein described that will
make a good substitute for the icebox. A barrel is sunk in the
ground in a shady place, allowing plenty of space about the
outside to fill in with gravel. A quantity of small stones and
sand is first put in wet. A box is pl