Jimmie escaped only by leading the professor to a secret cave of his own, though on some one else's property, where one not only could dig for arrow-heads, but find them.

The professor was delighted, but for Jimmie it was a great disappointment.

The week following Jimmie was again disappointed.
On the bank of the Kensico Reservoir, he came upon a man who was acting in a mysterious and suspicious manner.

He was making notes in a book, and his runabout which he had concealed in a wood road was stuffed with blue-prints.

It did not take Jimmie long to guess his purpose.