Two small detachments were sent into the friendly state of Michoacán, through which country they penetrated to the borders of the great Southern ocean. No European had as yet descended on its shores so far north of the equator. The Spaniards eagerly advanced into its waters, erected a cross on the sandy margin, and took possession of it, with all the usual formalities, in the name of their Catholic Majesties. On their return, they visited some of the rich districts towards the north, since celebrated for their mineral treasures, and brought back samples of gold and Californian pearls, with an account of their discovery of the ocean. The imagination of Cortés was kindled, and his soul swelled with exultation, at the splendid prospects which their discoveries unfolded. “Most of all,” he writes to the emperor, “do I exult in the tidings brought me of the Great Ocean. For in it, as cosmographers, and those learned men who know most about the Indies, inform us, are scattered the rich isles teeming with gold and spices and precious stones.”[140] He at once sought a favorable spot for a colony on the shores of the Pacific, and made arrangements for the construction of four vessels to explore the mysteries of these unknown seas. This was the beginning of his noble enterprises for discovery in the Gulf of California. Although the greater part of Anahuac, over-awed by the successes of the Spaniards, had tendered their allegiance, there were some, especially on the southern slopes of the Cordilleras, who showed a less submissive disposition. Cortés instantly sent out strong detachments under Sandoval and Alvarado to reduce the enemy and establish colonies in the conquered provinces. The highly colored reports which Alvarado, who had a quick scent for gold, gave of the mineral wealth of Oaxaca, no doubt operated with Cortés in determining him to select this region for his own particular domain.