Larry's face was pale, partly because he thought that the other would have succeeded in doing the mischief in spite of him. But the determined face of the boy, coupled with his words, made Croly pause, although he still allowed his hand to rest on the valve-gear of the great engine. "You think I don't know enough to start this machine, I suppose," he said. "I think if you did know, you wouldn't try to blow out the cylinder-heads to start with," Larry rejoined. "You're trying to bluff me now, but you ain't quite old enough to do it. Just wait till the five-minute whistle blows, and see if I can't start the machine. I know enough to know that if you let the steam into the cylinder, she's got to start." "Something would start, that's certain," said Larry, drily. "But," he continued, "I don't think you will let the steam on this time. Now, let go!" "You're a pretty heavy man to put in as boss of this plant," replied Steve. He let go of the valve-wheel, but did not step back. Larry divined that the fellow intended to wait until he was momentarily away from the gear, and then persist in his attempt to start the engine. "I told you to go out," he said, pointing at the door. "I'm going after the engine is started, and not before," persisted Croly. "You know you have no right in this part of the works. They wouldn't have me loafing in your department, and you must keep out of this!" "I don't try to send anybody away from my department." "You would if you had charge of it. In yours there is a foreman and fifty or sixty men; in this there is only the fireman, under the engineer, but the engineer is just as much a foreman as the boss of your department is there." "You're a boy," sneered Croly, "and when the Tioga Iron Works has boys put in as bosses, they'll have to turn off the men and run the whole business with boys. That's all there is to it." "Would you come here if my father was in charge?" "It isn't likely I should." "Then you admit that you have no right here?" Croly was silent. It was plain enough to Larry what the matter was with the young man. The truth was he had at some time been temporarily in charge of a small portable or "donkey" engine, such as are used for hoisting purposes in stone quarries and in other out-of-door work, and he was incapable of recognizing the difference between the simple construction of such a machine and the complicated work in the great motive-power of the Tioga Iron Works. Larry was a slow-spoken boy, and correspondingly slow in making a decision. But when his mind was really made up, he was equally slow to change it. He looked at the clock, and then at his own watch. In one minute the next whistle would blow, and then the engine must be started. The door leading to the boiler-room had been left open by Croly, and it had glass panels, through which Joe Cuttle could be seen hard at work, feeding the hungry furnaces.