four sustaining surfaces, the novelty
in the Sellers machine lies in the fact that it is operated successfully
with an 8 h. p. motor, which is the smallest yet used in actual flight.
In describing his work, Mr. Sellers says his purpose has been to develop
the efficiency of the surfaces to a point where flight may be obtained
with the minimum of power and, judging by the results accomplished,
he has succeeded. In a letter written to the authors of this book, Mr.
Sellers says:

"I dislike having my machine called a quadruplane, because the number of
planes is immaterial; the distinctive feature being the arrangement
of the planes in steps; a better name would be step aeroplane, or step
plane.

"The machine as patented, comprises two or more planes arranged in step
form, the highest being in front. The machine I am now using has four
planes 3 ft. x 18 ft.; total about 200 square feet; camber (arch) 1 in
16.

"The vertical keel is for lateral stability; the rudder for direction.
This is the first machine (so far as I know) to have a combination
of wheels and runners or skids (Oct. 1908). The wheels rise up
automatically when the machine leaves the ground, so that it may alight
on the runners.

"A Duthirt & Chalmers 2-cylinder opposed, 3 1/8-inch engine was used
first, and several hundred short flights were made. The engine gave
four brake h. p., which was barely sufficient for continued flight. The
aeroplane complete with this engine weighed 78 pounds. The engine now
used is a Bates 3 5/8-inch, 2-cylinder opposed, showing 8 h. p., and
apparently giving plenty of power. The weight of aeroplane with this
engine is now 110 pounds. Owing to poor grounds only short flights have
been made, the longest to date (Dec. 31, 1910) being about 1,000 feet.

"In building the present machine, my object was to produce a safe, slow,
light, and small h. p. aeroplane, a purpose which I have accomplished."

CHAPTER XXVII. 1911 AEROPLANE RECORDS.

THE WORLD AT LARGE.

Greatest Speed Per Hour, Whatever Length of Flight, Aviator Alone--E.
Nieuport, Mourmelon, France, June 21, Nieuport Machine, 82.72 miles;
with one passenger, E. Nieuport, Moumlelon, France, June 12, Nieuport
Machine, 67.11 miles; with two passengers, E. Nieuport, Mourmelon,
France, March 9, Nieuport Machine, 63.91 miles; with three passengers,
G. Busson, Rheims, France, March 10, Deperdussin Machine, 59.84 miles;
with four passengers, G. Busson, Rheims, France, March