oing 80 miles per hour. Viking 1 was a twin
tractor biplane driven by a 50 h.p. Gnome engine through chains. It was
built by the author at Hendon in 1912.

[Illustration: Plate XXXIII.]

Much ingenuity was exerted by the French designers in 1911 to
produce machines for the Military Trials. Among them was the 100 h.p.
Gnome-Borel monoplane with a four-wheeled chassis, and the Astra
triplane with a 75 h.p. Renault engine. This last had a surface of about
500 square feet and presented considerable possibilities. Its principal
feature was its enormous wheels with large size tyres as an attempt to
solve difficulties of the severe landing tests. The Clement-Bayard
biplane was a further development of the Clement-Bayard monoplane;
the type represented could be converted into a monoplane at will. The
Lohner Arrow biplane with the Daimler engine was an early German tractor
biplane built with a view to inherent stability, and proved very
successful. The Pivot monoplane was of somewhat unconventional French
construction, chiefly notable for the special spring chassis and pivoted
ailerons at the main planes; this pivoting had nothing to do with the
name of the machine, which was designed by M. Pivot.

[Illustration: Plate XXXIV.]

The Flanders monoplane, 1912, with 70 h.p. Renault engine, was one of
the last fitted with king-post system of wing bracing. The Flanders
biplane entered for British Military Trials. Notable features: the
highly staggered planes, extremely low chassis and deep fuselage. Also,
the upper plane was bigger in every dimension than the lower; about
the first instance of this practice. The Bristol biplane, with 100 h.p.
Gnome engine, was also entered for the Trials, but ultimately withdrawn.
The Mars monoplane, later known as the "D.F.W.," was a successful
machine of Taube type with 120 h.p. Austro-Daimler engine. The building
of the engine into a cowl, complete with radiator in front, followed car
practice very closely. The tail of the monoplane had a flexible trailing
edge; its angle of incidence could be varied from the pilot's seat,
so that perfect longitudinal balance was attained at all loadings and
speeds. The Handley-Page monoplane, with 70 h.p. Gnome engine, was an
early successful British attempt at inherent stability.

[Illustration: Plate XXXV.]

The Sommer monoplane, with 50 h.p. Gnome, was a 1911-12 machine; it did
a good deal of cross-country flying. The Vendome monoplane of 1912, also