Mount Buena Vista marks the entrance from the north into one of the largest and, for the future, one of the most important rivers of the world, the Rio de la Plata. The river was discovered in 1515 by Juan Diaz de Solis, and seems to have been named by Sebastian Cabot in 1520. The name (meaning “river of silver”) was not given it because of its fancied resemblance to silver-plate, for in reality its surface is always ruffled, and its colour and consistency would be better described by the “river of mud;” but the great amount of actual silver ore which was taken from the Indians along this river, and the fact that it was used as a highway for the transport of the metal to the coast, are responsible for the poetic name of this ever dirty stream. Though the waters are not sparkling, and the banks are not such as to call for an enthusiastic description, yet the Plata occupies a position unequaled among the rivers of the world. It drains the largest part of South America south of the Amazon basin, and with its many tributaries reaches from the mountains of eastern Brazil to the Andes, covering therefore almost the entire width of the continent from the Atlantic to the Pacific. While its basin is thus widely spread, the name Rio de la Plata is limited to the stream from the junction of the rivers Parana and Uruguay, to the Atlantic. It is one hundred and fifty miles in length, and about one hundred and twenty miles wide at its outer spread. From here it rapidly narrows, so that at Montevideo it is but fifty miles wide, while at Buenos Aires it is only twenty, and at the junction of its principle head waters, but four miles. Its peculiar water is generally noticeable far out in the Atlantic by the change in colour: from the bright blue of the subtropical seas to a dull green, and on closer approach to a dark brown. One of the most remarkable facts in the history of American discovery is the slowness with which the world has learned of the true natural resources of this region. The early Spaniards came here to obtain from the Indians, either by fair means or otherwise, such valuables as they possessed. Silver and gold were thus secured, and this led to the more important discoveries of the sources of these metals, which we now know are so widely spread over the continent. Little by little the Spaniards settled among the Indians; and then came a time when the English descended upon the Spaniards and relieved them of their treasures. One of the first of these British pirates was Sir Francis Drake, knighted and otherwise honoured by Queen Elizabeth for his heartless cruelty to, and valuable thefts from, the Spanish pioneers.