Coronado set forth from Culiacan, with three hundred and fifty Spaniards and eight hundred Indians, and, after reaching the source of the Gila, passed the mountains to the Rio del Norte. He wintered twice in the region now called New Mexico, explored it thoroughly from north to south, and then, striking off to the north east, crossed the mountains and wandering eastwardly as far north as the fortieth degree of latitude, he unfortunately found neither Quivara nor gold. A few wretched ruins of Indian villages were all the discoveries made by these hardy pioneers, and thus the enchanted kingdom eluded the grasp of Spain forever. The troop of strangers and Indians soon became disorganized and disbanded; nor was Alarcon more successful by sea than Coronado by land. His vessels explored the shores of the Pacific carefully, but they found no wealthy cities to plunder, nor could the sailors hear of any from the Indians with whom they held intercourse. In 1546, a desolating pestilence swept over the land, destroying, according to some writers, eight hundred thousand Indians, and, according to others, five-sixths of the whole population. It lasted for about six months; and, at this period, a projected insurrection among the black slaves and the Tenochan and Tlaltelolcan Indians, was detected through a negro. This menaced outbreak was soon crushed by Mendoza, who seized and promptly executed the ringleaders. A portion of the Visitador Sandoval's orders related to the convocation of the Mexican bishops with a view to the spiritual welfare of the natives, and the prelates were accordingly all summoned to the capital, with the exception of the virtuous Las Casas, whose humane efforts in behalf of the Indians, and whose efforts to free them from the slavery of the _repartimientos_ had subjected him to the mortal hatred of the planters. The council of ecclesiastics met; but it is probable that their efforts were quite as ineffectual as the humane decrees of the Emperor, and that even in the church itself, there may have been persons who were willing to tolerate the involuntary servitude of the natives rather than forego the practical and beneficial enjoyment of estates which were beginning to fall into the possession of convents and monastaries on the death of pious penitents.