The =Plata River=, 250 miles long, is much like a gulf, having a width of over 100 miles at its mouth between Capes Santa Maria in Uruguay and San Antonio in the Province of Buenos Aires. The Paraná River with many tributaries has two principal sources well up in Brazil and a total length of 2600 miles, about one half in or on the border of Argentine territory. At first flowing south it turns west between Argentina and Paraguay, and after receiving the Paraguay River again flows south in Argentina. From January to September, nine months, it is open to trans-Atlantic steamers to Rosario; for 6000 ton vessels, 12 foot draft, to Paraná or Colastiné, the port of Santa Fé; for smaller steamers up the Alto Paraná nearly to the Falls of La Guayra, a little above the northeast extremity of Argentina. Steamers of 7 foot draft go up the Paraguay to Asunción and smaller steamers to Corumbá in Matto Grosso, Brazil, 2000 miles from Buenos Aires, and beyond to Cuyabá. Forty-two miles up stream from Buenos Aires is Ibicuy, a port where a steam ferry operates, carrying trains to and from Zarate on the Buenos Aires side. A few small streams flow into lagoons with no outlet; a number in the Buenos Aires Province flow into the Atlantic. Farther south are rivers of more importance, among these the Rio Negro and the Colorado, the only ones of this section easily and regularly navigable. CLIMATE The climate of Argentina naturally varies on account of its wide range of latitude, as well as from increasing altitude in the mountainous section. The prevailing winds, the mountain barriers, and the sea also modify the climate in restricted locations. The conditions of temperature and rainfall are different from those in the northern hemisphere. Thus Tierra del Fuego and the south main land are more habitable than corresponding latitudes in Labrador, partly by reason of a southern equatorial current; it is an excellent region for sheep raising. At the same time it is colder than at similar latitudes of Western Europe, as the prevailing west winds are chilled by the mountains.