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.
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