known, and it will
register the bearing from the flying-boat to this station. It may be
turned upon another station, and this bearing also charted. The
intersection of these two wireless compass bearings gives the position
of the ship at sea. The radio compass is dependable day or night, and
is said to be quite as reliable as a sextant or other navigating
instruments.

Sailmakers to repair airplane fabrics, to sew new covers for
planes--these men must find an opportunity in flying. There are
literally thousands of wings, as yet unmade, which will carry the air
traffic of the future. It matters not whether men or women take up
this branch of the work, it must be done, and done with a conscience.
Like all other branches of the mechanical maintenance of an airplane,
careless work on the part of a sailmaker may mean disaster for the
pilot. One of the latest fatalities at a Long Island flying-field was
due to careless stitching, or weakness of fabric, which gave way under
great pressure due to high speed. The linen cover of an upper plane
ripped off at a height of one hundred and fifty feet, and the pilot
was killed in the fall of the machine.

Photographers may yet take the place of surveyors, or work hand in
hand with them in the making of aerial maps of the country. The map of
the future must be an aerial map, a mosaic map such as was used by our
army headquarters. Nothing can exceed the eye of the camera for
accuracy. Cameras bolted to airplanes, such as were used by our army
for reconnaissance, have already been used for mapping cities. The
mapping of the entire country in such a manner is only a matter of
time.

One thing which an aviation mechanic of any sort must bear in mind is
that he _must_ do his work with a conscience. True, he is handling
mute metal engines, or dumb wires and struts--but in his work he holds
the life of the pilot in his hand. It is not too much to say that
hundreds of pilots' lives have been saved by the conscientious work of
skilled mechanics who realized the danger of the air.

I have seen mechanics rush from a hangar in a frenzy of excitement
and agitation. "That machine must not go up; it has been repaired, but
not inspected!" They have done their work with a will in the army;
they have learned some of the dangers of flying and weak spots which
must be watched. The civilian mechanic must be taught many things.

First of all he must know the value of inspection. Every machine which
h