The north coast of Africa is of a different character to the rest of the continent. While the western coast looks to the broad Atlantic Ocean, and the waves which break on the southern apex lead to the ice of the pole, the north coast is separated from the neighbouring shores by a basin of moderate extent. It is a mountainous district which fills up the space between the Sahara and the Mediterranean. Towards the west the peaks of Atlas reach, even in this climate, to the region of eternal snow; on the east, towards the mouths of the Nile, the hills gradually sink down, and the plain of Barca rises little more than 1,000 feet above the sea level. Numerous chains of hills, at one time pressing close upon the sea, at another leaving more extensive plains upon the coast, cover the northern edge, which along the deep valleys of the mountain streams exhibits that vigorous and luxuriant vegetation so characteristic of Africa when not checked by want of water, although even these fruitful valleys are again in their turn broken by droughty, and therefore bare, table-lands and depressions. On this northern coast, toward the Mediterranean, opens the valley which, in extent of fruitful territory, is the largest in the whole continent. It occupies the north-east corner of Africa, which is only separated from Arabia by a narrow strip of sea, and carries its gleaming waters through the wide space from the subsidence of the table-land down to the coast, where for almost its whole remaining breadth the continent is filled up with the desert of Sahara.