A great light dawned on Carl during the reading of the letter—a light so strong that it left him blinking.
"Py chimineddy," he gurgled, "I know now vy dot Prady run off mit Matt! He say in der ledder dot he vants some brofessional to run dot air-ship. Vell, Matt knows more as anypody aboudt modors, und so Prady dook him off. Vat a high-hantet pitzness! Und Prady has captured a hornet oof he dit pud know it! He vill t'ink he has a handtful ven he dries to make Matt vork for him."
"From this," proceeded Harris, waving the letter, "it seems that Brady had already laid his plans to quit South Chicago. In the letter, over his own signature, he admits sending three of his men to steal the blue prints. By a chance, and owing to the course of events in keeping the driver of the air-ship from getting away with the other two thieves, this roll and the letter dropped into the hands of Motor Matt. Undoubtedly, Motor Matt has been taken to Willoughby's swamp."
"Und vere iss dot?" asked Carl.
"I know about the swamp," went on Harris, "for I helped some Chicago officers run down a couple of escaped prisoners there, once. It's a bad hole, but there is a sort of island in the middle of it that has been the resort of criminals for a good many years. To get through the water, and mud, and tangled bushes to the island is a hard job for any one who has to go on foot. Still, it can be done. Brady and his men, of course, can use the Hawk, and all they have to do is to sail through the air and drop down where they want to go. The difficulties of the swamp won't bother them at all. The place is about four miles from Lake Station, Indiana."
"Vell," said Carl, eagerly, "led's go dere. Der kevicker vat ve go, der kevicker vat ve can helup Matt. He iss my bard, und he needs me now."
The Dutch boy got up and started for the door. Bounding from his chair, Jerrold overtook him and grabbed his arm.
"Wait!" he commanded, "I've only got a faint grasp of the situation, but from what I can figure out you're going to need me. First, though, I want to hear all about this Motor Matt. He has done a whole lot for Hamilton Jerrold, and Jerrold is a man who always tries to pay his debts. Tell me how the blue prints got into the hands of Motor Matt."
"Aber ve vas in a hurry!" cried Carl. "Villoughpy's svamp iss a goot vays off, und——"
"You'll save time in the end by losing a little here and now," averred Jerrold, drawing Carl to a chair and pushing him down into it. "Go on! Give me the whole of it, between you, and be quick."