striking the bridge. They had hardly set sail again when another bridge came in sight, and they could see just beyond it a third bridge. It would never do to stop at every bridge and unship the mast; so Harry went on shore, borrowed a saw from a cooper's shop, and sawed six inches off from the top of the mast, after which the bridges gave them no more trouble.
The boys were very much interested in passing the first lock. They slipped into the lock behind a big canal-boat, which left just room enough between its rudder and the gate for the Whitewing. When the lockmen shut the gate behind the boat, and opened the sluices in the upper gate, the water rose slowly and steadily. The sides of the lock were so steep and black that the boys felt very much as if they were at the bottom of a well; but it was not many minutes before the water had risen so high that the upper gates were opened, and the big canal-boat and its little follower were released.
Passing through a lock in a small boat, and in
