"Is this one going to the other side?" asked Ned, as the two walked back toward the tank.
"I hope it will be the first of my new machines on the Western front," Tom answered. "But I've still got to perfect it in some details and then take it apart. After that, if it comes up to expectations, we'll begin making them in quantities."
"Did you get him?" asked Mr. Damon eagerly, as the two young men came back to join Mary and her friends.
"No, he got away," Tom answered.
"Did he try to blow up the tank?" asked Mr. Nestor, who had an abnormal fear of explosives. "Was he a German spy?"
"I think he's that, all right," said Ned grimly. "As to his endeavoring to blow up Tom's tank, I believe him capable of it, though he didn't try it to-night—unless he's planted a time bomb somewhere about, Tom."
"Hardly, I guess," answered the young inventor. "He didn't have a chance to do that. Anyhow we won't remain here long. Now, Ned, what about this chap? Is he really the one you saw up in the tree?"
"I not only saw him but I felt him," answered Ned, with a rueful look at his fingers. "He stepped right on me. And when he came inside the tank to-night I knew him at once. I guess he was as surprised to see me as I was to see him."
"But what was his object?" asked Mr. Nestor.
"He must have some connection with my old enemy, Blakeson," answered Tom, "and we know he's mixed up with Schwen. From the looks of him I should say that this Simpson, as he calls himself, is the directing head of the whole business. He looks to be the moneyed man, and the brains of the plotters. Blakeson is smart, in a mechanical way, and Schwen is one of the best machinists I've ever employed. But this Simpson strikes me as being the slick one of the trio."