"See here, where a piece of rubber has been broken or cut out of the tire. It makes a peculiar mark in the dirt every time the wheel goes around." "That's right, and it will be a good thing to trace the carriage by. Come on, we'll keep right after it." "Hold on a bit," suggested Ned, who, though not so quick as Tom Swift, frequently produced good results by his very slowness. "Are you going off and leave the airship here for some one to walk off with?" "Guess they wouldn't take it far," replied the young inventor, "but I'd better make it safe. I'll disconnect it so they can't start it, though if Andy Foger happens to come along he might slash the planes just out of spite. But I guess he won't show up." Tom took a connecting pin out of the electrical apparatus, making it impossible to start the aeroplane, and then, wheeling it out of sight behind a small barn, he and Ned went back to the carriage marks in the road. "Hurry!" urged Tom, as he started off in the direction of the village of Hurdtown, near where the cottage stood. "We will ask people living along the highway if they've seen a carriage pass." "But what makes you think they went off that way?" asked Ned. "I should think they'd head away from the village, so as not to be seen." "No, I don't agree with you. But wait, we'll look at the marks. Maybe that will help us." Peering carefully at the marks of horses' hoofs and the wheel impressions, Tom uttered a cry of discovery. "I have it!" he declared. "The carriage came from the village, and kept right on the other way. You're right, Ned. They didn't go back to town. "Are you sure?" "Of course. You can see for yourself; if the carriage had turned around the track would show, but it doesn't and, even if they turned on the grass, there'd be two lines of marks--one coming out here and one returning. As it is there is only a single set--just as if the carriage drove up here, took on its load, and continued on. This way, Ned." They hurried down the road, and soon came to a cluster of farm houses. Inquiries there, however, failed to bring anything to light, for either the occupants of the house had failed to notice passing vehicles, or there had been so many that any particular carriage was not recalled. And there were now so many impressions in the soft dirt of the highway--so many wheel tracks and hoof imprints--that it was impossible to pick out those of the carriage with the cut rubber tire. "Well, I guess it isn't of much use to go on any farther," spoke Ned, when they had traveled several miles and had learned nothing. "We'll try one more house, and then go back," agreed Tom. "We'll tell dad about what's happened, and see what he says."