to
give as good a view as possible.

Before passing to the year 1914 mention should be made of the feat
performed by Nesteroff, a Russian, and Pegoud, a French pilot, who were
the first to demonstrate the possibilities of flying upside-down and
looping the loop. Though perhaps not coming strictly within the purview
of a chapter on design (though certain alterations were made to the top
wing-bracing of the machine for this purpose) this performance was
of extreme importance to the development of aviation by showing the
possibility of recovering, given reasonable height, from any position in
the air; which led designers to consider the extra stresses to which an
aeroplane might be subjected and to take steps to provide for them by
increasing strength where necessary.

When the year 1914 opened a speed of 126 miles per hour had been
attained and a height of 19,600 feet had been reached. The Sopwith and
Avro (the forerunner of the famous training machine of the War period)
were probably the two leading tractor biplanes of the world, both
two-seaters with a speed variation from 40 miles per hour up to some
90 miles per hour with 80 horse-power engines. The French were still
pinning their faith mainly to monoplanes, while the Germans were
beginning to come into prominence with both monoplanes and biplanes of
the 'Taube' type. These had wings swept backward and also upturned
at the wing-tips which, though it gave a certain measure of automatic
stability, rendered the machine somewhat clumsy in the air, and their
performances were not on the whole as high as those of either France or
Great Britain.

Early in 1914 it became known that the experimental work of Edward
Busk--who was so lamentably killed during an experimental flight later
in the year--following upon the researches of Bairstow and others had
resulted in the production at the Royal Aircraft Factory at Farnborough
of a truly automatically stable aeroplane. This was the 'R.E.'
(Reconnaissance Experimental), a development of the B.E. which has
already been referred to. The remarkable feature of this design was that
there was no particular device to which one could point out as the cause
of the stability. The stable result was attained simply by detailed
design of each part of the aeroplane, with due regard to its relation
to, and effect on, other parts in the air. Weights and areas were so
nicely arranged that under practically any conditions the machine tended
to