He was vexed and annoyed to a degree he had never before experienced. And he knew deep down in his heart that it was because he was acting a dishonourable part toward the absent classmate. He began to lose sleep over it, and grew nervous and exceedingly unhappy. On the one hand, his home training had made him sensitive to moral standards. He would not have dared to write to his mother about the affair to ask her advice as to what he ought to do, because he knew without writing what she would say. On the other hand, his ambition goaded him to ignore what it called a technicality, tried to befog the issue by whispering that Bauer could not succeed without putting into the lamp the things which Walter had discovered already himself, and constantly insinuated that even if he had not happened to see Bauer's diagram, Walter would probably have worked it out in a day or two anyhow. He replied to his mother's letter briefly, saying he was unusually busy and adding that he did not think Bauer could come with him because he had been called home and would not in all likelihood return to Burrton. He said nothing in this letter about the lamp; he could not bring himself to mention it. And he knew when he posted the letter that the tone of it would make his mother ask questions because it was so different from the enthusiastic, jolly letters he had written before. It was during this week that he fixed on a certain evening to make a practical test of his lamp. He had guarded his secret successfully. Not a soul, including both instructors and students, knew the special work he had been doing. Among the great number of special and changing experiments going on in the shop it had not been difficult to keep his discovery to himself. He chose a night when a great social event was occurring in hopes that he might have the shop to himself. There were a few enthusiastic specialists who did considerable night work, but on this particular evening they went out early and by nine o'clock he found himself alone. The power which lighted the town of Burrton was the same as that in use at the school and was in operation day and night. The conditions seemed absolutely favorable to a test of his invention, and by ten o'clock Walter had made all connections and brought his electrodes into position. The only question with him was whether the heat of the arc would melt the soft metal teeth at the right time and with even regularity. He was pale and nervous with the tension of the work, his loss of sleep and his goading of conscience, and when the carbons started to glow with the familiar hiss, he started back as if someone had come in, and looked around the shop fearfully.