"They surely did! And unless I miss my guess they were in it, or around it, when we went through like a fellow carrying the football over the line for a touchdown." "In there when the tank broke open things?" "I think so. I didn't see them before, but they certainly ran out as we started away." "This has got to be looked into!" decided Tom. "Come on, Ned! It may be more of that spy business!" Tom Swift stopped the tank and prepared to get out. Chapter XVI The Old Barn "There's no use chasing after 'em, Tom," observed Ned, as the two chums stood side by side outside the tank and gazed after the three men running off across the fields as fast as they could go. "They've got too much a start of us." "I guess you're right, Ned," agreed Tom. "And we can't very well pursue them in the tank. She goes a bit faster than anything of her build, but a running man is more than a match for her in a short distance. If I had the Hawk here, there'd be a different story to tell." "Well, seeing that you haven't," replied Ned, "suppose we let them go--which we'll have to, whether we want to or not--and see where they were hiding and if they left any traces behind." "That's a good idea," returned Tom. The place whence the men had emerged was a portion of the old factory farthest removed from the walls the tank had crunched its way through. Consequently, that part was the least damaged. Tom and Ned came to what seemed to have been the office of the building when the factory was in operation. A door, from which most of the glass had been broken, hung on one hinge, and, pushing this open, the two chums found themselves in a room that bore evidences of having been the bookkeeper's department. There were the remains of cabinet files, and a broken letter press, while in one corner stood a safe. "Maybe they were cracking that," said Ned. "They were wasting their time if they were," observed Tom, "for the combination is broken--any one can open it," and he demonstrated this by swinging back one of the heavy doors. A quantity of papers fell out, or what had been papers, for they were now torn and the edges charred, as if by some recent fire. "They were burning these!" cried Ned. "You can smell the smoke yet. They came here to destroy some papers, and we surprised them!" "I believe you're right," agreed Tom. "The ashes are still warm." And he tested them with his hand. "They wanted to destroy something, and when they found we were here they clapped the blazing stuff into the safe, thinking it would burn there. "But the closing of the doors cut off the supply of air and the fire smouldered and went out. It burned enough so that it didn't leave us very much in the way of evidence, though," went on Tom ruefully, as he poked among the charred scraps. "Maybe you can read some of 'em," suggested Ned.