cooking in the open air
over bonfires. The illustration shows a laborsaving machine in use
which enables the cook to go away and leave meat roasting for an
hour at a time. The

[Illustration: For a Summer Camp]

illustration shows how the spit to which the meat is fastened is
constantly turned by means of a slowly moving water wheel. Some of
our readers may wish to try the scheme when camping out. The
success depends upon a slow current, for a fast-turning wheel will
burn the meat.

** A Short-Distance Wireless Telegraph [102]

The accompanying diagrams show a wireless-telegraph system that I
have used successfully for signaling a distance of 3,000 ft. The
transmitter consists of an induction coil, about the size used for
automobiles, a key or push-button for completing the circuit, and
five dry batteries. The small single-point switch is left open as
shown when sending a message, but when receiving it should be
closed in order that the electric waves from the antenna may pass
through the coherer. The coherer in this case is simply two
electric-light carbons sharpened to a wedge at one end with a
needle

[Illustration: Wiring Diagram for Wireless Telegraph]

connecting the two, as shown. An ordinary telephone receiver is
connected in series with the coherer, as shown. To receive
messages hold the receiver to the ear and close the switch, and
answer by opening the switch and operating the key. --Contributed
by Coulson Glick, Indianapolis.

** Automatic Draft-Opener [102]

A simple apparatus that will open the draft of the furnace at any
hour desired is illustrated. The parts are: A, furnace; B, draft;
C, draft chain; D, pulleys; E, wooden supports; F, vertical lever;
G, horizontal lever; H, cord; I, alarm clock; J, weight. K shows
where and how the draft is regulated during the day, the automatic

[Illustration: Draft Regulator]

device being used to open it early in the morning. The spool on
the alarm clock is fastened to the alarm key by sawing a slit
across the top of the spool and gluing it on. When the alarm goes
off a cord is wound up on the spool and pulls the horizontal lever
up, which releases the vertical lever and allows the weight to
pull the draft open.
--Contributed by Gordon Davis, Kalamazoo, Mich.

** A Window Conservatory [103]

During the winter months, where house plants are kept in the home,
it is always a question how to arrange them so they can get the
necessary light