“Maybe when the heel was cut out of block leather the knife slipped and left that mark,” Jordan thought. “With a plain marking like that we ought not to have much trouble. Let’s look under that tree where the cardboard was found.”

Under this tree they had more difficulty, because the feet of the curious cadets had churned up the ground so that it was almost impossible to make out anything definite. But at a distance of perhaps three yards they found the marked heel print again. Whoever had placed the sign in the tree had come down the slope above the camp, and the print could be followed for a short distance up the hillside. But before long they struck a section of rocky ground and hunt as they would they could not find another trace of the print.

“A whole lot of this Ridge is pretty rocky,” sighed Douglas. “From here on I guess we’ll have to trust to luck. Somewhere we may run across the trail again and get our bearings.”

They explored the slope with exhausting patience, but there was no further trace until they struck the very top of the hill. There, in a soft spot, they once more found their marking. The print pointed down toward the town of Rideway, which they could see in the distance.

“He went down into town,” said Terry. “Suppose we follow down there, and see where the print leads to?”

Following the marked heel down into Rideway was not an easy task. In some places they lost all traces of it and had to look around for half an hour before finding the faint mark again. But the trail led steadily down the opposite slope from the camp until it went into town. But here they lost it for good.

The main road was hard as a rock, with a glazed surface that left no trace of any mark. They followed this road down through town for a long way, but there was no further sign of the marked heel. Their next move was to look along the sides of the road to see if the man had walked off it at any point, but after a good hour had been spent in this way the cadets gave it up as a bad job.

“Too bad,” groaned Jim. “Right at the most important part we lose it altogether. I guess that’s the end of an important clue.”

“Yes, looks like we have exhausted this possibility,” agreed Jordan. “Anyway, we have given the town people something to wonder about.”

This was true. The natives of Rideway had been watching the boys with curiosity. So busy had they been in their search that they had failed to pay any attention to the citizens, but the people had not failed to note what they were doing.