5. In regard to Strato, however, we must remark that, leaving out of the question the many arguments he has properly 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 another 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 together 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. Consequently 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 account for the current he observed at the Strait of Byzantium in the manner he does, attributing it to the bed of the Euxine being higher than that of the Propontis and adjoining ocean, and even attempting to explain the cause thereof: viz. that the bed of the Euxine is filled up and choked by the deposit of the rivers which flow into it; and its waters in consequence driven out into the neighbouring sea. The same theory he would apply in respect to the Mediterranean and Atlantic, alleging that the bed of the former is higher than that of the latter in consequence of the number of rivers which flow into it, and the alluvium they carry along with them. In that case there ought to be a like influx at the Pillars and Calpe,[325] as there is at Byzantium. But I waive this objection, as it might be asserted that the influx was the same in both