stle had been
necessary.

"Think you can ride it, young man?" asked an elderly man, as Joe
halted, for he had to push the machine up the embankment.

"I'm going to make a big attempt," was the answer. "You see, I'm behind
my schedule and I've got to make it up."

"You're taking a big risk."

"Well, I'm used to risks," answered Joe with a smile. "I'm a circus
trapeze performer."

"That accounts for part of it," went on the man with a smile. "I wish
you luck."

"Thanks," murmured Joe as he began to push the heavy motor-cycle up the
embankment. Willing hands assisted him, and he soon stood on the
railroad tracks themselves. He found that the road-bed was in good
condition. The ties, or sleepers, as the wooden supports of the rails
are called, were well embedded in cinders, which had been finely
pulverized by the action of the weather and by many feet walking over
them, for the railroad tracks were often used as a short cut by the
people of the neighborhood.

"This won't be half bad to ride on," said Joe, as he kicked at the
cinders.

"No, but the trestle is the sticker," some one remarked. "You can't
ride on that without being shaken to pieces on the ties."

"I'm not going to try," Joe said. "As I told you, I'm going to take to
a rail."

"You'll never do it!" was the prediction. "I thought you were joking
when you said that."

"It's no joke for me if I miss getting to the circus on time," said Joe
grimly. "And if you watch you'll at least see me start. I'm not going
to guarantee where I'll end," he concluded as he took a careful survey
of the trestle which stretched out before him for more than a mile.

Joe was not going into this without having thought carefully of it in
advance, in spite of the short time it had taken him to make up his
mind. He was used to doing that--thinking and deciding quickly. The
very nature of his calling made it necessary for him to do this. One
does not have much time to make up one's mind when flying through the
air from a high trapeze.

Joe felt reasonably sure that if he could get his machine started at a
fast rate of speed, and could get it, at that speed, on top of the
smooth, and none too wide, rail, he could hold it there. It is a
well-known fact in physics that a body in motion tends to follow a
straight line, until forced out of that course by some external force.
If a stone is thrown it will go in a straight line until the attraction
of the earth's gravitation pulls