his course, and struggling with the wind-gusts which whistle
through the guy wires. The automatic mechanism restores the
angle of advance when compromised by variations of the breeze;
but when these come from one side and tilt the apparatus, the
weight has to be shifted to right the machine... these gusts
sometimes raise the machine from ten to twenty feet vertically,
and sometimes they strike the apparatus from above, causing it
to descend suddenly. When sailing near the ground, these
vicissitudes can be counteracted by movements of the body from
three to four inches; but this has to be done instantly, for
neither wings nor gravity will wait on meditation. At a height
of three hundred or four hundred feet the regulating mechanism
would probably take care of these wind-gusts, as it does, in
fact, for their minor variations. The speed of the machine is
generally about seventeen miles an hour over the ground, and
from twenty-two to thirty miles an hour relative to the air.
Constant effort was directed to keep down the velocity, which
was at times fifty-two miles an hour. This is the purpose of
the starting and gliding against the wind, which thus furnishes
an initial velocity without there being undue speed at the
landing. The highest wind we dared to experiment in blew at
thirty-one miles an hour; when the wind was stronger, we waited
and watched the birds.'

Chanute details an amusing little incident which occurred in the
course of experiment with the biplane glider. He says that 'We
had taken one of the machines to the top of the hill, and loaded
its lower wings with sand to hold it while we e went to lunch.
A gull came strolling inland, and flapped full-winged to
inspect. He swept several circles above the machine, stretched