The Sacramento and San Joachim are the principal rivers of California, but the Sacramento alone is navigable to any extent worthy of mention. There are numerous small streams and lakes in the interior, the principal outlet of which is the Colorado River. The valleys through which these streams flow are fertile, and afford good pasture for cattle; but the remainder of the region between the maritime and the Colorado ranges of mountains is a barren waste of sand. CHAPTER II. DISCOVERY OF CALIFORNIA. The first exploration of the Pacific coasts of North America was made by the Spaniards, in the sixteenth century. After Hernando Cortes had completed the conquest of Mexico, he commenced exploring the adjoining seas and countries; no doubt, with the hope of discovering lands richer than those which he had conquered, and which would afford new fields for the exercise of his daring enterprise and undaunted perseverance. He employed vessels in surveying the coasts of the Mexican Gulf, and of the Atlantic more northerly. Vessels were built upon the Pacific coast for like purposes, two of which as early as 1526, were sent to the East Indies. The first expedition of the Spaniards, sent along the western coast of Mexico, was conducted by Pedro Nunez de Maldonado, an officer under Cortes. He sailed from the mouth of the Zacatula River, in July, 1528, and was six months engaged in surveying the shores from his starting-place to the mouth of the Santiago River, a hundred leagues farther north-west. The territory he visited was then called Xalisco, and inhabited by fierce tribes of men who had never been conquered by the Mexicans. Flattering accounts of the fertility of the country and of the abundance of the precious metals in it were brought back by the expedition, and these served to excite the attention of the Spaniards. When the expedition returned Cortes was in Spain, whither he had gone to have his title and powers more clearly defined. He returned in 1530 with full power to make discoveries and conquests upon the western coast of Mexico. From the opposition of his enemies, he was prevented from fitting out an expedition before 1532. The most northern post upon the Pacific coast, occupied by the Spaniards, was Aguatlan, beyond which the coast was little known.