He was going to wait till the water brought the roof with Jim Leonard on
it down to the bridge, and then catch the hook into the shingles and
pull it up to the pier. The strongest current set close in around the
middle pier, and the roof would have to pass on one side or the other.
That was what Blue Bob argued out in his mind when he decided that the
skiff would never reach Jim Leonard, and he knew that if he could not
save him that way, nothing could save him.

Blue Bob must have had a last name, but none of the little fellows knew
what it was. Everybody called him Blue Bob because he had such a thick,
black beard that when he was just shaved his face looked perfectly blue.
He knew all about the river and its ways, and if it had been of any use
to go out with a boat, he would have gone. That was what all the boys
said, when they followed Blue Bob to the bridge and saw him getting out
on the pier. He was the only person that the watchman had let go on the
bridge for two days.

The water was up within three feet of the floor, and if Jim Leonard's
roof slipped by Blue Bob's guard and passed under the bridge, it would
scrape Jim Leonard off, and that would be the last of him.

All the time the roof was coming nearer the bridge, sometimes slower,
sometimes faster, just as it got into an eddy or into the current; once
it seemed almost to stop, and swayed completely round; then it just
darted forward.

Blue Bob stood on the very point of the pier, where the strong
stone-work divided the current, and held his hooked pole ready to make a
clutch at the roof, whichever side it took. Jim Leonard saw him there,
but although he had been holloing and yelling and crying all the time,
now he was still. He wanted to say, "O Bob, save me!" but he could not
make a sound.

It seemed to him that Bob was going to miss him when he made a lunge at
the roof on the right side of the pier; it seemed to him that the roof
was going down the left side; but he felt it quiver and stop, and then
it gave a loud crack and went to pieces, and flung itself away upon the
whirling and dancing flood. At first Jim Leonard thought he had gone
with it; but it was only the rat that tried to run up Blue Bob's pole,
and slipped off into the water; and then somehow Jim was hanging onto
Blue Bob's hands and scrambling onto the bridge.

Blue Bob always said he never saw any rat, and a good many people said
there never was any rat on the roof with Jim Leonard; t