ly
achieved. It designed and fitted up the instruments necessary for the
pilot's use, which record for him his speed through the air, the
consumption of his fuel, the rate of revolutions of his airscrew, the
height attained, and other essentials. The average pilot, it is well
known, is supplied with more instruments than he uses, but it is true
nevertheless that familiarity with the use of instruments has often
staved off disasters. At first the factory had refrained from initiating
engine designs, but when competition and trial had shown that there was
no immediate prospect of obtaining a thoroughly satisfactory engine from
English makers, it asked permission of the War Office, and in 1913
designed its own engine. Among its notable devices one or two may be
mentioned. The mooring-mast for airships, to which they can be tethered
in the open, was invented at the factory, and developed independently
for naval work, by the Admiralty. The fair-shaped wires and struts, to
decrease air resistance, were a great improvement. These parts of an
aeroplane offer so considerable a resistance to its passage through the
air, that when their transverse section, instead of being round, is
streamlined, the speed of the machine is increased by several miles an
hour. In short, during those early years the factory, which directly or
indirectly had to supply most of the requirements of the balloon school,
the Air Battalion, and the Royal Flying Corps, combined in itself all
the functions of what later on were highly organized separate Government
departments--inspection, stores, repairs, the testing of inventions, and
the like.

From what has been said it will be seen that the factory continued, as
it began, in close relations with the army. It had been founded, under
army auspices, at an important inland military centre, and it was not so
well adapted, by its history or situation, to serve the navy. The
results obtained by research at the National Physical Laboratory, and by
experiment at the factory, furthered the science of aviation, and were
open to all. But when flight began, a united national air force was not
thought of by any one, or was thought of only in dreams. Meantime the
new invention offered to the navy, no less than to the army, new
opportunities of increasing the power of its own weapon. The problems of
the navy were not the problems of the army, and a certain
self-protective jealousy made the two forces keep apart, so that e