Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/450

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Dialogue. IV.
421

Gulph, lesse by far than the rest of the Mediterrane, and placed in so different an inclination, that whereas that hath its bounds that incloseth it on the Eastern part, as are the Coasts of Syria, this is shut up in its more Westerly part: and because the ebbings and flowings are much greater towards the extremities, yea, because the Seas risings and fallings are there onely greatest, it may probably happen that the times of Flood at Venice may be the time of low Water in the other Sea, which, as being much greater, and distended more directly from West to East, cometh in a certain sort to have dominion over the Adriatick: and therefore it would be no wonder, in case the effects depending on the primary causes, should not hold true in the times that they ought, and that correspond to the periods in the Adriatick, as it doth in the rest of the Mediterrane. But these Particularities require long Observations, which I neither have made as yet, nor shall I ever be able to make the same for the future.

Sagr.You have, in my opinion, done enough in opening us the way to so lofty a speculation, of which, if you had given us no more than that first general Proposition that seemeth to me to admit of no reply, where you declare very rationally, that the Vessels containing the Sea-waters continuing stedfast, it would be impossible, according to the common course of Nature, that those motions should follow in them which we see do follow; and that, on the other side, granting the motions ascribed, for other respects, by Copernicus to the Terrestrial Globe, these same alterations ought to ensue in the Seas, if I say you had told us no more, this alone in my judgment, so far exceeds the vanities introduced by so many others, that my meer looking on them makes me nauseate them, and I very much admire, that among men of sublime wit, of which nevertheless there are not a few, not one hath ever considered the incompatibility that is between the reciprocal motion of the Water contained, and the immobility of the Vessel containing, which contradiction seemeth to me now so manifest.

Salv.It is more to be admired,One single motion of the terrestrial Globe sufficeth not to produce the Ebbing & Flowing that it having come into the thoughts of some to refer the cause of the Tide to the motion of the Earth, therein shewing a more than common apprehension, they should, in afterwards driving home the motion close with no side; and all, because they did not see that one simple and uniform motion, as v. gr. the sole diurnal motion of the Terrestrial Globe, doth not suffice, but that there is required an uneven motion, one while accelerated, and another while retarded: for when the motion of the Vessels are uniforme, the waters contained will habituate themselves thereto, without ever making any alteration. To say also (as it is related of an ancient

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