On the same evening, after the men had wrapped themselves up in their blankets and laid down for a sleep, and while enjoying their slumbers, a noise reached their ears which sounded very much like distant thunder; but a close application of the sense of hearing showed plainly that an enemy was near at hand.  Springing up, with rifle in hand—­for generally in the mountains a man’s gun rests in the same blanket with himself on all sleeping occasions—­they sallied forth to reconnoitre, and discovered a few warriors driving along a band of at least two hundred horses.  The trappers comprehended instantly that the warriors had been to the Mexican settlements in Sonora on a thieving expedition, and that the horses had changed hands with only one party to the bargain.  The opportunity to instill a lesson on the savage marauders was too good to be lost.

They saluted the thieves with a volley from their rifles, which, with the bullet-whizzing about their heads and bodies, so astonished them, that they seemed almost immediately to forget their stolen property, and to think only of a precipitous flight.  In a few moments, the whites found themselves masters of the field, and also of the property.  To return the animals to their owners was an impossibility; Mr. Young, therefore, selected as many of the best horses as he needed for himself and men, and game being very scarce, killed two and dried most of the meat for future use, turning the remainder loose.  Such either became wild mustangs or fell again into the clutches of the Indians.  The company then renewed their trapping, and continued it up the Gila to a point opposite the copper mines of New Mexico.  Here they left the river and proceeded to the copper mines, where they found Mr. Robert McKnight engaged in trading with the neighboring Indian tribes.  These mines were not then, and ever since have not been, worked.  The holes which had many years before been made by the miners—­but who they were is unknown—­formed a safe hiding-place for their skins.  The stock of beaver was therefore placed under the care of Mr. McKnight.  Young and his men then renewed their march, and in due time arrived safely at Santa Fe.  Here they purchased licenses to trade with the Indians who live about the copper mines.  With these licenses as protection papers, they returned to where the skins were concealed.  Having once more recovered their fur, they returned with it to Santa Fe.  The deserted mines of New Mexico show incontrovertible signs of having been successfully and extensively worked, at some remote period, for various kinds of metals.  They have proved a knotty historical problem to many an investigating mind; for their authentic history has fallen, and probably will ever remain in oblivion.  It may have been that about a century ago the Spaniards, with Indian assistants, worked them; and the savages becoming hostile to their employers, in some sudden fit of frenzy may have massacred the Spaniards.  There