The lakes differ from the mediterraneans; the first do not receive any water from the ocean; on the contrary, if they have communication with the seas, they furnish them with water. Thus the Black Sea, which some geographers have regarded as an arm of the Mediterranean, and consequently as an appendix of the ocean, is only a lake, because, in place of receiving water from the Mediterranean, it supplies it with some, and flows with rapidity through the Bosphorus into the lake called the Sea of Marmora, and from thence through the Strait of the Dardanelles into the Grecian Sea. The Black Sea is about 250 leagues long by 100 broad, and it receives a great number of rivers, as the Danube, the Nieper, the Don, the Boh, the Donjec, &c. The Don, which unites with the Donjec, forms, before it arrives at the Black Sea, a lake, called the Palus Meotis, which is more than 100 leagues in length by 20 or 25 broad. The sea of Marmora, which is below the Black Sea, is a smaller lake than the Palus Meotis, being not more than 50 leagues long and 8 or 9 broad. Some ancients, and among the rest Diodorus Siculus, have asserted that the Euxine, or Black Sea, was formerly only a large river or lake, and had no communication with the Grecian sea; but being considerably increased with time by the rivers which fell into it, the waters forced a passage at first on the side of the Cyanean islands, and afterwards on the side of the Hellespont. This opinion appears to be very probable, and the operation is easily explained; for supposing the bottom of the Black Sea was formerly lower than it is at present, then the rivers which come into it would have raised it by the mud and sand which they brought with them, until the surface of the water became higher than the land, when consequently it would have forced a passage for itself, and as the rivers still continue to bring sand and earth, and at the same time the quantity of water diminishes in the rivers, in proportion as the mountains from which they drew their sources are lowered, it may happen in a course of years that the Bosphorus will be again filled up; but as these effects depend on many causes, it is scarcely possible to give more than mere conjectures thereon. From this testimony of the ancients, Mr. Tournefort, in his voyage to the Levant, says, on ancient authority, that the Black Sea receiving the waters of a great part of Europe and Asia, after being considerably increased, opened itself a passage by the Bosphorus, and afterwards formed the Mediterranean, or so considerably augmented it, that it became a great sea, and forced itself a road through the strait of Gibraltar, by which the island of Atlantis, mentioned by Plato, was entirely overflowed. This opinion has no foundation, since we are certain that it is the ocean which flows into the Mediterranean, and not the Mediterranean into the ocean. Besides, M. Tournefort has not combined two essential