80 STEABO. BOOK i. uncovered and has experienced so many changes, as Eratos- thenes has observed. Consequently in the reasoning of Xan- thus there does not appear to be any thing out of place. 5. In regard to Strato, however, we must remark that, leaving out of the question the many arguments he has pro- perly stated, some of those which he has brought forward are quite inadmissible. For first he is inaccurate in stating that the beds of the interior and the exterior seas have not the same level, and that the depth of those two seas is different : whereas the cause why the sea is at one time raised, at an- other depressed, that it inundates certain places and again retreats, is not that the beds have different levels, some higher and some lower, but simply this, that the same beds are at one time raised, at another depressed, causing the sea to rise or subside with them ; for having risen they cause an inundation, and when they subside the waters return to their former places. For if it is so, an inundation will of course accompany every sudden increase of the waters of the sea, [as in the spring-tides,] or the periodical swelling of rivers, in the one instance the waters being brought to- gether from distant parts of the ocean, in the other, their volume being increased. But the risings of rivers are not violent and sudden, nor do the tides continue any length of time, nor occur irregularly ; nor yet along the coasts of our sea do they cause inundations, nor any where else. Con- sequently we must seek for an explanation of the cause either in the stratum composing the bed of the sea, or in that which is overflowed ; we prefer to look for it in the former, since by reason of its humidity it is more liable to shiftings and sudden changes of position, and we shall find that in these matters the wind is the great agent after all. But, I repeat it, the immediate cause of these phenomena, is not in the fact of one part of the bed of the ocean being higher or lower than another, but in the upheaving or depression of the strata on which the waters rest. Strato's hypothesis evidently originated in the belief that that which occurs in rivers is also the case in regard to the sea ; viz. that there is a flow of water from the higher places. Otherwise he would not have attempted to ac- count for the current he observed at the Strait of Byzantium in the manner he does, attributing it to the bed of the Euxine being
