off for the woods. A fair-sized tree was selected, and
the boys, without a word to indicate that they wanted him to assist,
began to cut down the tree.

He looked on wistfully for a time, and then edged his way over and made
a motion to take Harry's place, to which he assented. It was now
impossible for Harry to regain his place at the tree, and when it fell
he acted and looked like a conqueror, and Harry patted him on the back
as a token of his good work. A section of the butt of the tree was cut
off, and loaded on the truck, and dragged to the sawmill. The end had to
be squared off, and Chief insisted on doing this, the use of the
exceedingly novel tool being the greatest pleasure, evidently, that he
had ever enjoyed.

The fixing of it to the reciprocating saw frame was a marvel to him, and
when he saw the boards cut off his joy knew no bounds. The proceedings
at the sawmill delighted the Professor. "I have always contended, as
heretofore expressed, that the same motive which prompts us to do things
with pleasure is to know that we are doing things which produce
results."

And then Harry did another graceful thing. He turned up a number of
brass balls which he gave to Chief. If there is one thing a savage loves
better than another, it is something round. That is why beads are so
attractive, and buttons, and small trinkets of that kind. They are like
children in this respect. Put a cube and a ball, both of the same
material, before a child, and he will usually select the ball. It is a
psychological phase which has never been explained; and the same test
has been made with monkeys.

CHAPTER X

UNAWARES IN THE ENEMY'S COUNTRY

During the evening, while engaged in their usual discussions the
surveying implement was brought up, and it was understood that a crude
instrument should be made, so that it would be ready within the next
week.

While speaking on the subject of laying off the segments into degrees,
the former matter of observing the heavens was alluded to, and Ralph
inquired why all calculations of the heavens were made by degrees.

"Because degrees mean angles and not measurements. Positions or
distances are determined by angles and by measurements in miles."

"But in looking at the stars how can mariners tell where they are,
simply by getting the angles?"

"That is a matter which can be calculated with such accuracy on the high
seas that the distance can be determined with absolute certainty