Allan had learned as much of the science of train-dispatching as it is possible to do without actual experience, and he was duly appointed operator at headquarters and extra dispatcher. He had a desk in the dispatchers' office, where he worked ten and sometimes twelve hours a day receiving and sending the multitudinous messages which passed between the various officials of the road. This work was in one way not such good training for a future dispatcher as a trick out on the road, for here he had nothing whatever to do with the movement of trains; but on the other hand he was constantly in touch with the dispatchers, he could listen to their conversation and pick up matters of detail which no one would have thought to tell him; in such leisure moments as he had, he could sit down before the train-sheet and watch the actual business of dispatching trains; he could see how unusual problems were solved and unusual difficulties met; and all the information picked up thus, as it were, at haphazard, he stored away for future use, certain that it would some day be needed. Not infrequently one of the dispatchers would relinquish his chair to him, and, for an hour or so, look after the operator's duties, while Allan did the actual work of dispatching. But he knew that this was not a real test, for, in case of emergency, help was always at hand. It was with him much as it is with those amateur sociologists who assume the garb and habits of the poor, and imagine that they are tasting all the misery of life in the slums; forgetting that its greatest misery, its utter hopelessness, they can never taste, since they have only to walk out and away from the life whenever they choose, and be rid of it for ever. So Allan, in case of need, had only to lift his finger, and aid was at hand. But at last the time came around when one of the dispatchers was to take his vacation; and one night, Allan reported for duty, to take the third trick on the east end. It was not without a certain tingling of the nerves that he sat down in the chair, looked over the sheet, and carefully read the written explanation of train-orders in force which the second-trick man had prepared for him. "Understand?" the latter asked, when Allan had finished. "Yes, I think so," said the boy, and the dispatcher, nodding, took up his lunch-basket and left the office. The weight of responsibility weighed on the boy for a time, and it was with no little nervousness that he transmitted his first order; but this feeling gradually wore away and was replaced by one of confidence. After all, there was no cause to worry. The position of every train was marked there on the sheet before him; there was no excuse for mistake. And yet, as he thought of those mighty engines rushing through the night with their precious burdens, obedient to his orders, his pulses quickened with a sense of power.