The muleteer had advanced into the narrow channel when he suddenly cast a hurried glance behind him, uttered a "Madre de Dios!" and backed his mule and his precious freight against the bank.

The sound of hoofs on the trail in their rear had caught his quicker ear, and as the three partners turned they beheld three horsemen thundering down the hill towards them.

They were apparently Mexican vaqueros of the usual common swarthy type, their faces made still darker by the black silk handkerchief tied round their heads under their stiff sombreros.

Either they were unable or unwilling to restrain their horses in their headlong speed, and a collision in that narrow passage was imminent, but suddenly, before reaching its entrance, they diverged with a volley of oaths, and dashing along the left bank of the arroyo, disappeared in the intervening willows.

Divided between relief at their escape and indignation at what seemed to be a drunken, feast-day freak of these roystering vaqueros, the little party re-formed, when a cry from Barker arrested them.