"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." "But what made him come here, and what did he want?" asked Mary. "Dear me! it's like one of those moving picture plots, only I never saw one with a tank in it before--I mean a tank like yours, Tom." "Yes, it is a bit like moving picture--especially chasing Simpson by searchlight," agreed the young inventor. "As to what he wanted, I suppose he came to spy out some of my secret inventions--dad's and mine. He's probably been hiding and sneaking around the works ever since we arrested Schwen. Some of my men have reported seeing strangers about, but I have kept Shop Thirteen well guarded. "However, this fellow may have been waiting outside, and he may have followed the tank when we started off a little while ago for the night test. Then, when he saw our mishap and noticed that we were stalled, he came in, boldly enough, thinking, I suppose, that, as I had never seen him, he would take a chance on getting as much information as he could in a hurry." "But he didn't count on Ned's being here!" chuckled Mr. Damon. "No; that's where he slipped a cog," remarked Mr. Nestor. "Well, Tom, I like your tank, what I've seen of her, but it's getting late and I think Mary and I had better be getting back home." "We'll be ready to start in a little while," Tom said, after a brief consultation with one of his men. "Still, perhaps it would be just as well if you didn't ride back with me. She may go all right, and then, again, she may not. And as it's dark, and we're in a rough part of the field, you might be a bit shaken up. Not that the tank minds it!" the young inventor hastened to add "She's got to do her bit over worse places than this--much worse--but I want to get her in a little better working shape first. So if you don't mind, Mary, I'll postpone your initial trip." "Oh, I don't mind, Tom! I'm so glad you've made this! I want to see the war ended, and I think machines like this will help." "I'll ride back with you, Tom, if you don't mind," put in Ned. "I guess a little shaking up won't hurt me." "All right--stick. We're going to start very soon." "Well, I'm coming over to-morrow to have a look at it by daylight," said Mr. Damon, as he started toward his car. "So am I," added Mary. "Please call for me, Mr. Damon." "I will," he promised.