to fly."

The first very light engine to be available was the _Antoinette_,
built by Leon Levavasseur in France. It enabled Santos-Dumont to make
his first public successful flights. Nearly all aeroplanes follow the
same general principles of construction. Of course a good deal depends
upon the form of aeroplane--whether a monoplane or a biplane. As these
two forms are the chief ones, as yet, of heavier than-air machines,
it would be well to understand them. The monoplane has single large
surfaces like the wings of a bird, the biplane has two large surfaces
braced together one over the other. At the present writing a triplane
has been introduced into the domain of American aviation by an English
aeronaut. Doubtless as the science progresses many other variations
will appear in the field. Most machines, though fashioned on similar
lines, possess universal features. For instance, the Wright biplane
is characterized by warping wing tips and seams of heavy construction,
while the surfaces of the Herring-Curtiss machine, are slight and it
looks very light and buoyant as if well suited to its element. The
Voisin biplane is fashioned after the manner of a box kite and therefore
presents vertical surfaces to the air. Farman's machine has no vertical
surfaces, but there are hinged wing tips to the outer rear-edges of
its surfaces, for use in turning and balancing. He also has a
combination of wheels and skids or runners for starting and landing.

The position to be occupied by the operator also influences the
construction. Some sit on top of the machine, others underneath. In
the _Antoinette_, Latham sits up in a sort of cockpit on the top.
Bleriot sits far beneath his machine. In the latest construction of
Santos-Dumont, the _Demoiselle_, the aviator sits on the top.