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cept the head of it. Perhaps it is presumed,
though, that his heavy goggles
are sufficient.
j»
CLOCK THAT SPEAKS THE
TIME
A CLOCK that will "speak the time"
^^ every fifteen minutes has been invented
by a well known civil engineer.
This clock differs very little from the
ordinary clock, having the same face and
standard works, with the exception that
to the minute shaft of the clock is fastened
an automatic lever and cam, which
is actuated every fifteen minutes by the
minute wheel.
This lever acts upon a second lever
attached to a drum carrying a phonographic
film. The action of the first
upon the second lever starts an electric
motor, causing the film to move. When
the film begins to move the stylus of the
phonographic reproducer is acted upon
and the time is vocally announced or
spoken. Of course, the film is so made
as to announce the time in accordance
with the adjustment of the machine.
The phonographic reproducer is fitted
with a small horn which intensifies the
Don't Count the Strokes
This little clock announces the hour in an audible tone.
sound. The clock is also fitted with a
repeating device so as to repeat the hour
any number of times.
In the making of the film the voice
impression is recorded for the twelve
hours. These impressions are made
upon a soft wax drum, which is covered
HINTS FOR PRACTICAL PEOPLE 753
with graphite and put into a copper
electro plating bath. A sufficiently
heavy coat of copper is put on and the
wax melted off, leaving a thin copper
ring containing the voice impression.
St
FLASHLIGHT HELMETS
(~\N account of the war, English police
^ are equipped with electric lights in
their helmets. These are of the flashlamp
type, and can be switched on and
off rapidly for signaling purposes, so
that during a Zeppelin raid, when the
streets are pitch black, their use is apparent.
They also appear to provide a
satisfactory method of communicating
with other policemen in the event of
riots, street fights, and other such disturbances.
The light is supplied with current
from a small battery carried on the belt.
St
HUMIDITY HEALTH INSUR­
ANCE
IT is hard to realize, but it is true,
nevertheless, that when an ordinary
living room is heated to a temperature
of seventy degrees, an artificial climate
is created drier than that of any desert.
If we were on a desert, however, we
would hardly be surprised at the harm
done to the mucous membrane in the