all want that part to attach
the top pulley between."

Now that it was cut and trimmed, the problem was to convey it back to
the river.

"Do you think we can induce the yaks to swim across the river?"

"That's a capital idea, Harry, let us go back and try it."

"While you are getting the animals I shall do some investigating," said
the Professor.

The boys crossed the river and took the two-wheeled truck across. "It
might be amusing to the Professor, if he found we had taken the truck
across before we knew whether the yaks could be induced to go over."
Harry laughed at George, and answered: "How shall we manage it? We had
better keep them yoked, I suppose."

After some urging, they were driven to the water, the boys having tied a
rope to the yoke before they went into the river. To their great
surprise and relief, the yaks made no objections, and immediately
started out at a great rate for the opposite shore, and before they had
gone twenty feet were swimming. The boys in the raft held on tightly and
were drawn across without further trouble.

As they left the river for the trip, they distinctly heard a shot.

"I wonder what the Professor has shot? Did you hear him?" They listened
intently. The shot appeared to come from a point considerably to the
left of the place where the pole had been cut, but they paid little
attention to that. After they had gone halfway another shot was heard,
this time at a point which indicated that the Professor must be some
distance away.

As anticipated, the Professor was not in the location of the pole.

"I don't think the Professor expected us back so soon," was Harry's
suggestion. "Let us rig up the pole and hitch the team, and by that time
he may be back."

In less than a half hour this was done, ready for a start; still no
signs of the Professor.

"I think we had better fire a shot to let him know we are here."

"Singular we didn't think of that before; here goes." Waiting fully a
quarter of an hour after the shot, they were surprised at not hearing
any response from him. "I wonder," continued Harry, "if he has met with
some accident?"

"We heard it in this direction, didn't we? Don't let us waste any more
time. Get the guns and ammunition. Hurry up; and let us take a spear; it
may be useful."

Each boy took a spear, as a matter of precaution, and set out. At
intervals the boys shouted, and after wandering about for fully a half
hour, determined to try another shot.