HYDRAULIC ARCHITECTURE, BOOK III.

...the Archipelago The Aegean Sea., given its great distance from the Ocean. But if one considers that the strait The Strait of Gibraltar. is only about 5 leagues wide by 10 leagues long, one would find it difficult to conceive how the Ocean could provide a current strong enough to produce all these complex movements original: "bricolemens"; refers to the shifting, rebounding, or oscillating patterns of water within a basin., even if the Mediterranean were lower than the Ocean—despite our reluctance to believe this. For even supposing that this had been the case in the past, shouldn't this sea, by virtue of receiving the waters of the Ocean for so many centuries, now be level with it? This is even without accounting for the losses it might suffer from evaporation, which seem to be replaced by the rivers that discharge into it. It appears that this prejudice—if indeed it is one—stems from the claim that ships have greater ease passing from the Ocean into the Mediterranean during the flood tide The rising tide that flows toward the shore or into a channel. than they find in leaving it, even when aided by a favorable wind.

The Mediterranean Sea is not the only one deprived of a considerable ebb and flow; everyone knows that the Baltic Sea and the Euxine Sea The Black Sea. have none, and that several others are in the same situation due to their lack of communication with the Ocean. This is not to mention the Caspian Sea and some gulfs, even though they lie beneath the passage of the moon's body; because their extent is less than that of the "great circle" of this planet Bélidor refers to the moon as a "planet" here, common in older scientific writing. The "great circle" refers to the moon's area of gravitational influence., the diameter of which is estimated at 725 leagues, its action occurs everywhere equally, and thereby prevents the ebb and flow. Thus, it is only in vast seas that exceed the capacity of the moon's great circle that one observes this movement and the successive effect that follows.

603. To say also a word about the Red Sea—of which we shall have occasion to speak particularly when mentioning the enterprises of the ancients to join it to the Mediterranean by a canal—there is nothing so contradictory as what some authors have written about it. Some claim that the tides there are stronger than in any sea in the world; others, on the contrary, that it has none at all. But Scaliger Julius Caesar Scaliger (1484–1558), a famous polymath who studied physics and natural history. and several celebrated writers report that, in truth, this sea never rises nor falls toward the middle of its length, which is about 350 leagues; but that toward the Isthmus of Suez, at its most northern extremity, its tide is nearly the same as at Venice—that is to say, about 3 feet—and that at the southern extremity, these waters merely participate more or less in what occurs in the Ocean of which they are a part; this has been confirmed for us