pulled and bent and twisted the mud-guard,
wrenching it off. The wheel revolved freely now. The spokes were
beginning to shine in the brightening light.

And meanwhile the seconds passed!

It was the work of hardly a minute to bind three other narrow strips of
shingle among the spokes so that they stood more or less crossways.
There was no time to place and fasten more, but these, at equal
intervals, forming a sort of cross within the wheel, were quite
sufficient, Tom thought, for his purpose. It was necessary to shave the
edges of the shingles somewhat, after they were in place, so that they
would not chafe against the axle-bars. But this was also the hurried
work of a few seconds, and then Tom moved his machine to the old mooring
float and lifted it upon the bobbing platform.

He must work with the feverish speed of desperation for the float was
held by no better anchor than one of its supporting barrels embedded in
the mud. If he placed his weight or that of _Uncle Sam_ upon the side of
the float already in the water the weight would probably release the
mud-held barrel and the float, with himself and _Uncle Sam_ upon it,
would be carried willy-nilly upon the impetuous waters.

And meanwhile---- How plainly he could distinguish the trees now, and
the pale stars stealing away into the obscurity of the brightening
heavens.

With all the strength that he could muster he wrenched a board from the
centre of the platform, and moving his arm about in the opening felt the
rushing water beneath.

The buoyancy of the air-tight barrels, one of which was lodged under
each corner of the float, was such that with Tom and his machine upon
the planks the whole platform would float six or eight inches free of
the water. To pole or row this unwieldy raft in such a flood would have
been quite out of the question, and even in carrying out the plan which
Tom now thought furnished his only hope, he knew that the sole chance of
success lay in starting right. If the float, through premature or
unskilful starting, should get headed downstream, there would be no hope
of counteracting its impetus.

Lifting his machine, he lowered it carefully into the opening left by
the torn-off plank, until the pedals rested upon the planks on either
side and the power wheel was partially submerged. So far, so good.

In less than a minute now he would either succeed or fail. It was
necessary first to alter the position of the float slightly so that