Next the lower gates are opened, the water in the lock seeks the lower level of the other section of the canal, and the boat moves out of the lock, the water subsiding gradually beneath it.

Next, the lower gates are closed, and the boat proceeds on its way.

It will easily be understood, when the case is reversed, and the boat is going up, how after being admitted into the lock it will be lifted up to the higher level when the upper gates are thrown open.
If any of my young readers find it difficult to understand my explanation, I advise them to read Jacob Abbot's excellent book, "Rollo on the Erie Canal," where the whole matter is lucidly explained.
Railroads were not at that time as common as now, and the canal was of much more importance and value as a means of conveying freight.
Sometimes passengers traveled that way, when they were in not much of a hurry, but there were no express canal-boats, and a man who chose to travel in that way must have abundant leisure on his hands.

There is some difference between traveling from two to two and a half miles an hour, and between thirty and forty, as most of our railroad express trains do.
James did not have to wait long after his engagement before he was put on duty.

With boyish pride he mounted one of the mules and led the other.