Atlantic were not the same, and states that a bank of earth, the remains of the ancient separation of the two seas, is still stretched under water from Europe to Africa. He adds, that the Euxine is the most shallow, and the seas of Crete, Sicily, and Sardinia much deeper, which is occasioned by the number of large rivers flowing into the Euxine both from the north and east, and so filling it up with mud, whilst the others preserve their depth. This is the cause of the remarkable sweetness of the Euxine Sea, and of the currents which regularly set towards the deepest part. He gives it as his opinion, that should the rivers continue to flow in the same direction, the Euxine will in time be filled up [by the deposits], since already the left side of the sea is little else than shallows, as also Salmydessus,[319] and the shoals at the mouth of the Ister, and the desert of Scythia,[320] which the sailors call the Breasts. Probably too the temple of Ammon was originally close to the sea, though now, by the continual deposit of the waters, it is quite inland: and he conjectures that it was owing to its being so near the sea that it became so celebrated and illustrious, and that it never would have enjoyed the credit it now possesses had it always been equally remote from the sea. Egypt too [he says] was formerly covered by sea as far as the marshes near Pelusium,[321] Mount Casius,[322] and the Lake Sirbonis.[323] Even at the present time, when salt is being dug in Egypt, the beds are found under layers of sand and mingled with fossil shells, as if this district had formerly been under water, and as if the whole region about Casium and Gerrha[324] had been shallows reaching to the Arabian Gulf. The sea afterwards receding left the land uncovered, and the Lake Sirbonis remained, which having afterwards forced itself a passage, became a marsh. In like manner the borders of the Lake Mœris resemble a sea-beach rather than the banks of a river. Every one will admit that formerly at various periods a great portion of the mainland has been covered and again left bare by the sea. Likewise that the land now covered by the sea is not all on the same level, any more than that whereon we dwell; which is now uncovered and has experienced so many changes, as Eratosthenes has observed. Consequently in the reasoning of Xanthus there does not appear to be any thing out of place.