Then, again, Walter kept going over the great advantage it would be to him if this discovery were made by him first. He knew that the commercial value of any real improvement in city lighting was very large. There was money for him in this discovery. And Walter was growing more and more restless over his stewardship and the burdens it involved. He hated the drudgery and the time it took, and of late he began to feel quite certain that the same attitude displayed in other schools was creeping into Burrton, an attitude of contempt for the working student, nothing very pronounced, but enough to make him feel disagreeable and annoyed, for he was a finicky youth, sensitive to a great degree and with the taste of an aristocrat at heart. "I don't see that I do Bauer any harm if I go ahead and make a model. I'll do that anyhow," he said out loud at last, as he got up and turned on his light. And then he saw under the edge of his door a note which had been slipped in there. He went over, picked it up, opened it, and found it was a note from Bauer. "My Dear Douglas:--Within an hour after leaving the shop to-night I had a telegram calling me home. I do not know how soon I shall be able to return to Burrton, if at all. Will you kindly see if I left any of my apparatus or papers on my table and return them to my locker? I enclose the key with this note. Thank you. "FELIX BAUER." So Bauer was going to be away indefinitely. He might not come back at all. He had not given any reason for the call to come home, but Walter remembered one remark the German student had made one day which led him to believe that Bauer's home life was unhappy and the relations between his father and mother were unpleasant. Suppose he never came back. Suppose he never finished his investigation of the lamp? Suppose--there was a number of possibilities to suppose. Why, then the field would be open to him and he could go ahead with a clear conscience. But could he? In spite of all sophistry and special pleading with himself Walter knew he had caught the idea of the electrodes from Bauer's drawing, which suggested the secret. How did he know but that Bauer had discovered it as indicated in his own diagram and was making that preliminary to the finished lamp?