A cloud of dust rose behind the odd outfit as the party drew out on the plains. Their ponies were started at a gallop, which was necessary to enable them to keep up with the pace that Juan had set.
"Here! Here!" shouted the Professor.
Juan never looked back.
"We're leaving the pack train. Slow down!"
Laughingly the lads pulled their ponies down to a walk; then halted entirely to enable the burros to catch up with them. By this time the pack animals had become so familiar with their work that little attention was necessary on the part of the boys. Now and then one more sleepy than the rest would go to sleep and pause to doze a few minutes on the trail. This always necessitated all hands stopping to wait until the sleeper could be rounded up and driven up to the bunch.
Juan had disappeared. They were discussing the advisability of sending one of the boys out after him when he was seen returning. But at what a different gait! His burro was dragging itself along with nose to the ground, while Juan himself was slouching on its back half asleep.
"You must have a motor inside that beast," grinned Tad.
"Him go some, señor?"
"Him do," answered Stacy, his solemn eyes taking in the sleepy burro wonderingly.
"Better not waste your energy performing," advised the Professor. "We shall need what little you have. We will make camp here, as I see there is a spring near by. Help the boys unpack the burros."