again in 1904 with a similar apparatus large enough to
carry a passenger, but the longitudinal equilibrium was
found to be defective. Then in 1907 a new machine was
tested, in which four sets of frames, carrying similar sets
of slat "sustainers" were inserted, and with this
arrangement the longitudinal stability was found to be very
satisfactory. The whole apparatus, with the operator,
weighed 650 pounds. It flew about 200 yards when
driven by a motor of 20 to 22 h.p. at 30 miles an hour,
thus exhibiting a lift of about 32 pounds per h.p., while
it will be remembered that the aeroplane of Wright
Brothers exhibits a lifting capacity of 50 pounds to
the h.p.

Hargrave's Kite Experiments.

After experimenting with very many models and
building no less than eighteen monoplane flying model
machines, actuated by rubber, by compressed air and by
steam, Mr. Lawrence Hargrave, of Sydney, New South
Wales, invented the cellular kite which bears his name
and made it known in a paper contributed to the Chicago
Conference on Aerial Navigation in 1893, describing
several varieties. The modern construction is well
known, and consists of two cells, each of superposed surfaces
with vertical side fins, placed one behind the other
and connected by a rod or frame. This flies with great
steadiness without a tail. Mr. Hargrave's idea was to
use a team of these kites, below which he proposed to
suspend a motor and propeller from which a line would