Upwards of five hundred miles away to the south of the spot where the traveller stands, is the little lake of Lauricocha, near the silver-mines of Cerro de Pasco in Peru, just below the limit of perpetual snow--14,000 feet above the level of the sea. This lake has the honour of giving birth to the mighty stream: its waters forming the River Tunguragua, which, roaring and foaming in a series of cataracts and rapids through rocky valleys, flows northerly till it reaches the frontier of Ecuador. It then turns suddenly to the east, which direction it maintains, with a slightly northerly inclination, for two thousand miles--its volume greatly increased by numerous large streams, each of which is by itself a mighty river--till, attaining a width which may vie with that of the Baltic, it rushes with such fierce force into the Atlantic as to turn aside on either hand the salt-waters of the ocean. Thus the seaman approaching the shore of South America, when still out of sight of land, may lower his bucket and draw up the fresh-water which, it may be, has issued forth weeks before from the sides of the Andes. The whole length of the river, following its main curves, is but little under three thousand miles, while the tributaries from north to south stretch over seventeen hundred miles. The basin of the Amazon may be considered like a shallow trough lying parallel to the equator, the southern sides having double the inclination of the northern, the whole gently sloping eastward. The channel of the river lies rather to the north of the basin, some hills rising directly above its waters; while the falls of several rivers to the south are two hundred miles above their mouths. Two thousand miles from its mouth the depth of the river is never less than eighteen feet, while many of its tributaries at their embouchures are of equal depth; and at the junction of the great rivers the hollows of its bed attain a depth of twenty-four fathoms. At Tabalingua, two thousand miles from its mouth, it is a mile and a half broad; and lower down, at the entrance of one of its tributaries--the Madeira--it measures three miles across. Still further to the east its sea-like reaches extend to the north for ten miles, with still wider lake-like expanses, so that the eye of the voyager can scarcely reach the forest-covered banks on the opposite side; while if the River Para is properly considered one of its branches, its measurement from shore to shore, across a countless number of islands, is one hundred and eighty miles--equal to the breadth of the widest part of the Baltic.