loud, pass twice over the
Seine which at that point makes an abrupt bend, sail over the Bois
de Boulogne, circle the Tower, and return to the stopping place
within a half an hour. The distance was about seven miles, and it is
noteworthy that in his own comment on the test Santos-Dumont
complains that that required an average speed of fifteen miles an
hour of which he could not be sure with his balloon. To-day
dirigibles make sixty miles an hour, and airplanes not infrequently
reach 130 miles. Moreover there could be no picking of a day on
which atmospheric conditions were especially good. Mr. Deutsch had
stipulated that the test must be made in the presence of a
Scientific Commission whose members must be notified twenty-four
hours in advance. None could tell twenty-four hours ahead what the
air might be like, and as for utilizing the aviator's most
favourable hour, the calm of the dawn, M. Santos-Dumont remarked:
"The duellist may call out his friends at that sacred hour, but not
the airship captain."

The craft with which the Brazilian first strove to win the Deutsch
prize he called _Santos-Dumont No. V._ It was a cylinder, sharp at
both ends, 109 feet long and driven by a 12-horse-power motor. A new
feature was the use of piano wire for the support of the car, thus
greatly reducing the resistance of the air which in the case of the
old cord suspensions was almost as great as that of the balloon
itself. Another novel feature was water ballast tanks forward and
aft on the balloon itself and holding together twelve gallons. By
pulling steel wires in the car the aviator could open the
stop-cocks. The layman scarcely appreciates the very slight shift in
ballast which will affect the stability of a dirigible. The shifting
of a rope a few feet from its normal position, the dropping of two
handfuls of sand, or release of a cup of water will do it. A
humorous writer describing a lunch with Santos-Dumont in the air
says: "Nothing must be thrown overboard, be it a bottle, an empty
box or a chicken bone without the pilot's permission."

After unofficial tests of his "No. 5" in one of which he circled the
Tower without difficulty, Santos-Dumont summoned the Scientific
Commission for a test. In ten minutes he had turned the Tower, and
started back against a fierce head-wind, which made him ten minutes
late in reaching the time-keepers. Just as he did so his engine
failed, and after drifting for a time his ship perched in the to