"Bother it! It won't come right! I quite forget how Mr. Delermain said I was to do it. I will run and ask him again; he won't mind my bothering him." He took his book and went out. The corridor leading to the masters' rooms was rather dark, for the gas had either not been lit, or had been turned out by some one. Just before the room was reached the corridor turned sharply to the right, and here it was quite dark. And, as Ralph turned this corner, he encountered some one, who ran against him with such force that he almost fell down; and before he could recover from his surprise, that unseen boy had disappeared round the corner, running swiftly and silently, as if anxious to escape notice. Ralph muttered something about clumsy fellows, and picked up his papers, which had been scattered in all directions. Then he went on to Mr. Delermain's room, and saw that the door was open, but the room in darkness. His master had evidently finished his letters and gone. "I shall have to let it wait until to-morrow," he said. "It's jolly vexing, just as I was getting on so nicely." He turned from the door, when a step sounded in the corridor, and a light glimmered round the corner. Some one was coming. And then a voice said-- "Why, Rexworth, what are you doing here? You have no business in this corridor." And Ralph found himself face to face with Dr. Beverly. CHAPTER XII THE STOLEN BANKNOTE Now, why Ralph should have felt in the slightest degree confused by the sudden appearance of Dr. Beverly, he could not have said; and yet he was conscious that he exhibited something of hesitation in his manner. It was perhaps due to the doctor finding him there in the dark, and looking rather suspicious and stern. The fact was that the doctor was so used to his pupils playing tricks and getting into scrapes, that it was but natural that he should scan the boy's face closely, and he noted that Ralph looked confused. He repeated his question sharply, and then the boy recovered himself and described how he had come to ask Mr. Delermain to again explain the point which had escaped his memory. "Mr. Delermain has gone out, I believe," Dr. Beverly said, when Ralph concluded. "But perhaps I may be able to make the point clear. Come to my study and let me see what you are doing." Ralph followed the doctor, not without some little nervousness; for, like all the boys, he stood somewhat in awe of the head master; but the doctor smiled, and was so kind that he soon put the boy at ease; and, after scanning the neat rows of figures in the exercise-book, he nodded approval. "I am glad to see that you work so neatly, Rexworth," the Head said. "Now, this point. Here is your error--it is very simple, though easily made."