added to the rear rudder, to which a movable elevator was later
attached; and, finally, the front elevator was done away with.
It will thus be seen that having started from the very different
standpoints of automatic stability and complete control by the
pilot, the Voisin (as developed in the Farman) and Wright
machines, through gradual evolution finally resulted in
aeroplanes of similar characteristics embodying a modicum of
both features.

Before proceeding to the next stage of progress mention should
be made of the experimental work of Captain Ferber in France.
This officer carried out a large number of experiments with
gliders contemporarily with the Wrights, adopting--like
them--the Chanute biplane principle. He adopted the front
elevator from the Wrights, but immediately went a step farther
by also fitting a fixed tail in rear, which did not become a
feature of the Wright machine until some seven or eight years
later. He built and appeared to have flown a machine fitted
with a motor in 1905, and was commissioned to go to America by
the French War Office on a secret mission to the Wrights.
Unfortunately, no complete account of his experiments appears to
exist, though it can be said that his work was at least as
important as that of any of the other pioneers mentioned.



II. MULTIPLICITY OF IDEAS

In a review of progress such as this, it is obviously
impossible, when a certain stage of development has been