Juan started; then, with a sheepish grin, became busy again.
It was no small task to get their belongings in packs preparatory to the journey; but late in the afternoon the boys had completed their task. They had had nothing to eat since early morning. But they were too anxious to be on their way to wait for dinner in town.
After making some necessary purchases in the village, the procession finally started away across the plain.
"You'll never get anywhere with that sleepy burro, Juan," decided the Professor, with a shake of the head.
"Him go fast," grinned the Mexican.
"So can a crab on dry land," jeered Ned.
Just then the guide utter a series of shrill "yi-yi's," whereupon the lads were treated to an exhibition such as they never had seen before.
The sleepy burro projected his head straight out before him, while his tail, raised to a level with his back, stuck straight out behind him. The burro, seemingly imbued with sudden life, was off at a pace faster than a man could run.
It was most astonishing. The boys gazed in amazement; then burst out in a chorus of approving yells.
But it was the rider, even more than the burro, that excited their mirth. His long legs were working like those of a jumping jack, and though astride of the burro, Juan was walking at a lively pace. It reminded one of the way men propelled the old-fashioned velocipedes years before.