thus produced was made by the French firm of Darracq
at the suggestion of Santos Dumont, and on lines laid down by him.
Santos Dumont wanted a 2-cylinder horizontal motor capable of developing
30 horsepower, and not exceeding 4 1/2 pounds per horsepower in weight.

There can be no question as to the ability and skill of the Darracq
people, or of their desire to produce a motor that would bring new
credit and prominence to the firm. Neither could anything radically
wrong be detected in the plans. But the motor, in at least one important
requirement, fell short of expectations.

It could not be depended upon to deliver an energy of 30 horsepower
continuously for any length of time. Its maximum power could be secured
only in "spurts."

This tends to show how hard it is to produce an ideal motor for aviation
purposes. Santos Dumont, of undoubted skill and experience as an
aviator, outlined definitely what he wanted; one of the greatest
designers in the business drew the plans, and the famous house of
Darracq bent its best energies to the production. But the desired end
was not fully attained.

Features of Darracq Motor.

Horizontal motors were practically abandoned some time ago in favor of
the vertical type, but Santos Dumont had a logical reason for reverting
to them. He wanted to secure a lower center of gravity than would be
possible with a vertical engine. Theoretically his idea was correct as
the horizontal motor lies flat, and therefore offers less resistance to
the wind, but it did not work out as desired.

At the same time it must be admitted that this Darracq motor is a marvel
of ingenuity and exquisite workmanship. The two cylinders, having a bore
of 5 1-10 inches and a stroke of 4 7-10 inches, are machined out of a
solid bar of steel until their weight is only 8 4-5 pounds complete.
The head is separate, carrying the seatings for the inlet and exhaust
valves, is screwed onto the cylinder, and then welded in position. A
copper water-jacket is fitted, and it is in this condition that the
weight of 8 4-5 pounds is obtained.

On long trips, especially in regions where gasolene is hard to get,
the weight of the fuel supply is an important feature in aviation. As a
natural consequence flying machine operators favor the motor of greatest
economy in gasolene consumption, provided it gives the necessary power.

An American inventor, Ramsey by name, is working on a motor which
is said to possess great possibilit