Two hundred and eighty years before the Christian era, the large fresh-water lake of Oitz, in Japan, was formed in one night, by a prodigious sinking of the ground, at the same time that one of the highest and most active volcanos in that country rose from the depths of the earth. Very extensive lakes occur in Africa; there appears to be a great number on the low-lands on the east coast of Africa, in which many of the rivers from the edge of the table-land terminate. Among others, there is the salt lake Assal, 25 miles west of Tadjurra, in the country through which the Hawash flows, which has a depression of more than 700 feet below the level of the ocean, by Dr. Beke’s estimation, who first observed that curious circumstance; but by the actual measurement of Lieutenant Christopher, it is 570 feet. Notwithstanding the arid soil of the southern table-land, it contains the fresh-water lake of N’yassi or Zambeze, one of the largest, being some hundred miles long; and, though narrow in proportion, it cannot be crossed in a boat of the country in less than three days, resting at night on an island, of which there are many. It lies between 300 and 400 miles west from the Mozambique Channel, and begins 200 miles north of the town of Tete, which is situate on the river Zambeze, from whence it extends from south-east to north-west, possibly to within a degree or two of the equator. It receives the drainage of the country to the south-east: but no river is known to flow out of it, unless it be the Bahr-el-Abiad or White Nile, which probably rises in this lake. No one knows what there may be in the unexplored regions of the Ethiopian desert; but Abyssinia has the large and beautiful lake of Dembia, situate in a spacious plain—the granary of the country—so high above the sea that spring is perpetual, though within the tropics. There are many other lakes in this great projecting promontory, so full of rivers, mountains, and forests; but the lowlands of Soudan and the country lying along the base of the northern declivity of the table-land is the region of African lakes, of which the Tchad, almost the size of an inland sea, is in the very centre of the continent. Its extent, and the size of its basin, are unknown; it receives many affluents from the high lands called the Mountains of the Moon, certainly all those that flow from them east of Bornou, and it is itself drained by the Tchadda, a principal tributary of the Niger. Other lakes of less magnitude are known to exist in these regions, and there are probably many more that are unknown. Salt-water lakes are numerous on the northern boundaries of the great lowland deserts, and many fine sheets of fresh water are found in the valleys and flat terraces of the Great and Little Atlas.