will remain afloat.

If you shift your body well forward it will bring the
front edges of the glider down, and elevate the rear ones.
In this way the air will be "spilled" out at the rear, and,
having lost the air support or buoyancy, the glider comes
down to the ground. A few flights will make any ordinary
man proficient in the control of his apparatus by his
body movements, not only as concerns the elevating and
depressing of the advancing edges, but also actual steering. You
will quickly learn, for instance, that, as the
shifting of the bodily weight backwards and forwards
affects the upward and downward trend of the planes, so
a movement sideways--to the left or the right--affects
the direction in which the glider travels.

Ascends at an Angle.

In ascending, the glider and flying machine, like the
bird, makes an angular, not a vertical flight. Just what
this angle of ascension may be is difficult to determine.
It is probable and in fact altogether likely, that it varies
with the force of the wind, weight of the rising body,
power of propulsion, etc. This, in the language of physicists,
is the angle of inclination, and, as a general thing,
under normal conditions (still air) should be put down as
about one in ten, or 5 3/4 degrees. This would be an ideal
condition, but it has not, as vet been reached. The force
of the wind affects the angle considerably, as does also
the weight and velocity of the apparatus. In general