tion of a fish's fins and tail move it up, down, forward, or back, its
weight being nearly the same as the water it displaces.

The theory seems so simple that it strikes one as strange that the
problem of aerial navigation was not solved long ago. The story of
Santos-Dumont's experiments, however, his adventures and his successes,
will show that the problem was not so simple as it seemed.

Santos-Dumont was built to jockey a Pegasus or guide an air-ship, for he
weighed but a hundred pounds when he made his first ascensions, and
added very little live ballast as he grew older.

Weight, of course, was the great bugbear of every air-ship inventor,
and the chief problem was to provide a motor light enough to furnish
sufficient power for driving a balloon that had sufficient lifting
capacity to support it and the aeronaut in the air. Steam-engines had
been tried, but found too heavy for the power generated; electric motors
had been tested, and proved entirely out of the question for the same
reason.

Santos-Dumont has been very fortunate in this respect, his success,
indeed, being largely due to the compact and powerful gasoline motors
that have been developed for use on automobiles.

Even before the balloon for the first air-ship was ordered the young
Brazilian experimented with his three-and-one-half horse-power gasoline
motor in every possible way, adding to its power, and reducing its
weight until he had cut it down to sixty-six pounds, or a little less
than twenty pounds to a horse-power. Putting the little motor on a
tricycle, he led the procession of powerful automobiles in the
Paris-Amsterdam race for some distance, proving its power and speed. The
motor tested to his satisfaction, Santos-Dumont ordered his balloon of
the famous maker, Lachambre, and while it was building he experimented
still further with his little engine. To the horizontal shaft of his
motor he attached a propeller made of silk stretched tightly over a
light wooden framework. The motor was secured to the aeronaut's basket
behind, and the reservoir of gasoline hung to the basket in front. All
this was done and tested before the balloon was finished--in fact, the
aeronaut hung himself up in his basket from the roof of his workshop and
started his motor to find out how much pushing power it exerted and if
everything worked satisfactorily.

On September 18, 1898, Santos-Dumont made his first ascension in his
first air-ship--in fact, he had neve