The great detective arose from his seat and began pacing the apartment, as was his custom when deeply thinking.

Several times Mr. Herron attempted to break him from his thoughts, but Nick imperatively motioned him to silence. At length, he stopped short, and, turning to Mr. Herron, said:

“Under your statement, there is justification for your belief that the sole object of that burglary was the obtaining of that case, which, you say, contains all the matter relating to the invention. Still, I am inclined to believe that that burglary was the work of professionals.”

“Then we are far apart in the way we look at it,” said Mr. Herron.

“Not necessarily,” replied Nick, sharply. “Let me ask you, are these promoters you speak of as desiring possession of this invention men who have a fair standing before the world?”

“Yes; I must admit that,” said Mr. Herron.

“Are they men, do you think, who would, in their great desire to obtain possession, themselves commit a burglary?”

“Oh, no; and I don’t want you to think that they are banded together against me. They are as antagonistic to each other as they are to me.”

“I should assume that, in any event,” said Nick. “But suppose that there was one so much more desirous than the other to obtain possession that he would even engage in desperate means, do you think he would commit a burglary? To take the chances of ruining his reputation by entering a house at night?”

“It is very hard to believe it, in the way you put it.”