find the original Walter's note? We can compare the signature, and that will tell whether it is Walter or not."

The Professor smiled as he noticed the eagerness of the boys. They rushed out of the room and went over to the shop to reclaim the note that had given them so much concern fourteen months before.

When they had gone John said: "I presume you have already guessed what the note contains?"

"Unquestionably it has reference to the location of the main ledge of copper or other ore which is measured from some point in that vicinity, and which may be determined later on by noting the place where the missive was found, or from some natural landmark."

"That is my view, but I felt it would be better forp. 37 the boys to dig it out for themselves," replied John.

The wonderful nature of the instruction which the boys had obtained during their stay on the island, was characterized by this little incident. Everything learned by one's own exertions is not only more valuable because of that fact, but the facts thus gleaned will leave a stronger impress upon the mind.

The boys thus learned by doing things themselves, that they became strong and self reliant, and it made them happy to think that they were able to pick up the threads, however tangled, and weave them into a harmonious whole. It is the secret of doing things well.

p. 38