icated flame to
the envelope of the balloon, and Wolfert, together with a passenger he
carried, was either killed by the fall or burnt to death on the ground.
Giffard had taken special precautions to avoid an accident of this
nature, and Wolfert, failing to observe equal care, paid the full
penalty.

[*] Hildebrandt.

Platz, a German soldier, attempting an ascent on the Tempelhofer Field
in the Schwartz airship in 1897, merely proved the dirigible a failure.
The vessel was of aluminium, 0.008 inch in thickness, strengthened by an
aluminium lattice work; the motor was two-cylindered petrol-driven; at
the first trial the metal developed such leaks that the vessel came
to the ground within four miles of its starting point. Platz, who was
aboard alone as crew, succeeded in escaping by jumping clear before the
car touched earth, but the shock of alighting broke up the balloon, and
a following high wind completed the work of full destruction. A second
account says that Platz, finding the propellers insufficient to drive
the vessel against the wind, opened the valve and descended too rapidly.

The envelope of this dirigible was 156 feet in length, and the method
of filling was that of pushing in bags, fill them with gas, and then
pulling them to pieces and tearing them out of the body of the balloon.
A second contemplated method of filling was by placing a linen envelope
inside the aluminium casing, blowing it out with air, and then admitting
the gas between the linen and the aluminium outer casing. This would
compress the air out of the linen envelope, which was to be withdrawn
when the aluminium casing had been completely filled with gas.

All this, however, assumes that the Schwartz type--the first rigid
dirigible, by the way--would prove successful. As it proved a failure on
the first trial, the problem of filling it did not arise again.

By this time Zeppelin, retired from the German army, had begun to
devote himself to the study of dirigible construction, and, a year
after Schwartz had made his experiment and had failed, he got together
sufficient funds for the formation of a limitedliability company, and
started on the construction of the first of his series of airships. The
age of tentative experiment was over, and, forerunner of the success of
the heavier-than-air type of flying machine, successful dirigible flight
was accomplished by Zeppelin in Germany, and by Santos-Dumont in France.

III. SANTOS-DUMONT