Spain determined to take possession of the Plate, and in 1526 sent out an expedition for that purpose under Diego Garcia. At the same time Sebastian Cabot was preparing another expedition, which was ordered to follow in Magellan's track and to make observations of longitude on the Atlantic coast of South America and in the East Indies. Spain and Portugal had already begun to dispute about the correct location of the line which they had agreed should divide the world into a Spanish and a Portuguese hemisphere, and which was believed to pass near the Plate. Garcia was delayed on the coast of Brazil, so Cabot reached the mouth of the estuary first. The latter had encountered bad weather and lost his best ship, and when he sighted the coast of Uruguay his men were discouraged. They remained in the mouth of the river for some time, and to their surprise a solitary Spaniard was encountered on the shore, who proved to be the only survivor of the party that had gone ashore with Solis ten years before. Soon Cabot and his men heard tales of silver mines far up the river, and of the existence of a great civilised empire on its remote headwaters. Silver ornaments were shown which had come down hand to hand from Peru or Bolivia. Cabot determined to abandon his commission to the Moluccas, and to find the country whence the silver came. Naturally, his first effort was directed up the broad channel of the Uruguay, but on ascending this river it was soon evident that the mines and civilised country he was seeking did not lie on its banks. Fifty miles up the river at San Salvador the Spaniards attempted to establish a little post which is sometimes referred to as the earliest settlement in Uruguay or Argentina. It was probably intended as a mere supply depot and point of refuge, conveniently near the sea to aid the up-river expedition. However, the warlike Indians of Uruguay soon left no trace of it. Cabot entered the Parana, where he spent three years in an unsuccessful effort to reach Bolivia. He and Garcia sailed back to Spain without leaving even a settlement behind them, but they were thoroughly convinced that an adequate expedition could find the silver country.