At a little distance, where the details of construction are not visible, the Bleriot machine has the appearance of a gigantic bird. The sustaining surface, consisting of a single plane, is divided into two wings made of a stiff parchment-like material, mounted one on each side of a framework of the body, which is built of mahogany and whitewood trussed with diagonal ties of steel wire. The main plane has a lateral spread of 28 feet and a depth of 6 feet, and is rounded at the ends. It has an area of about 150 square feet, and is slightly concave on the under side. The tail-plane is 6 feet long and 2 feet 8 inches in depth; at its ends are the elevators, consisting of pivoted wing tips each about 2 feet 6 inches square with rounded extremities. The rudder for steering to left or right is mounted at the extreme rear end of the body, and has an area of 9 square feet. [Illustration: The Bleriot “No. XII.,” showing new form of tail, and the complete encasing with fabric.] The body is framed nearly square in front and tapers to a wedge-like edge at the rear. It extends far enough in front of the main plane to give room for the motor and propeller. The seat for the pilot is on a line with the rear edge of the main plane, and above it. The forward part of the body is enclosed with fabric. [Illustration: Forward chassis of Bleriot monoplane, showing caster mounting of wheels. The framing of the body is shown by the dotted lines.] The machine is mounted on three wheels attached to the body: two at the front, with a powerful spring suspension and pivoted like a caster, and the other rigidly at a point just forward of the rudders. The lateral balance is restored by warping the tips of the main plane; if necessary, the elevator tips at the rear may be operated to assist in this. All the controls are actuated by a single lever and a drum to which the several wires are attached. [Illustration: Diagram of Bleriot “No. XI.,” from the rear. _A_, _A_, main plane; _B_, tail; _C_, body; _D_, _D_, wing tips of tail; _E_, rudder; _H_, propeller; _M_, motor; _O_, axis of wing tips; _R_, radiator; _a_, _a_, _b_, _b_, spars of wings; _h_, _h_, guy wires; _p_, _k_, truss.] The motors used on the Bleriot machines have varied in type and power. In the “No. XI.,” with which M. Bleriot crossed the English Channel, the motor was a 3-cylinder Anzani engine, developing 24 horse-power at 1,200 revolutions per minute. The propeller was of wood, 2-bladed, and 6 feet 9 inches in diameter. It was mounted directly on the shaft, and revolved at the same speed, giving the machine a velocity of 37 miles per hour. This model has also been fitted with a 30 horse-power R-E-P (R. Esnault-Pelterie) motor, having 7 cylinders. The heavier type “No. XII.” has been fitted with the 50 horse-power Antoinette 8-cylinder engine, or the 7-cylinder rotating Gnome engine, also of 50 horse-power.