"Why, building up the fires," said Marco, "to set the engine a-going. They call it firing up."
Just at this moment there broke forth a loud and hoarse hissing from the steam-pipe, and a dense column of white vapor began to ascend, which mingled its snowy volumes, in a beautiful manner, with the dark masses of the smoke.
"They are blowing off the steam," said Marco.
"What does that mean?" asked the boy.
"Why, that they have got the steam up, and are letting off a little of it, while they are waiting for something. Perhaps they are waiting for us. Drive on as fast as you can."
A moment after this, the sound of the steam suddenly ceased, and the great paddle wheels, on the sides of the boat, began slowly to revolve.
"They are trying to get her off," said Marco. "I do hope they can't start her. Drive on; drive on as fast as you can."
They were, at this time, upon the top of a hill which commanded a fine view of the river, and of the scenery upon its banks. The mill was before them, too, in full view. But Marco was too much engaged in watching the movements of the boat to regard the scenery. The boy drove rapidly down the hill. They reached the mill in a very few minutes, and drove down to the bank of the river, by a road which led to the water, a short distance above the mill. But, in the mean time, unfortunately for Marco, the steamboat had regained its liberty, and when Marco and the boy came in view of it again, as their horse stopped at the edge of the water, they saw, to Marco's dismay, that she was ploughing her way swiftly up the river, being just about to disappear behind a point of land which terminated the view of the water in that direction.
"They are gone," said Marco, in a tone of despair, "they are gone; and what shall I do?"
"Can't you go in the stage?" asked the boy, hoping thus to say a word of encouragement and consolation.