have some Tinctures of the Lime, Chalk, or Clay; and the same happens to Minerals. But, some are naturally Sulphureous; as for example, Some sorts of hot Baths are as naturally Sulphureous, as the Sea-water is Salt: but, all those Effects of Minerals, Sulphurs, and the like, are dividable from, and also may be joyn'd to, the Body of water, without any disturbance to the nature of water; as may be proved by Salt-water, which will cause fresh Meat to be salt; and salt Meat will cause Fresh-water to be salt. As for hot Baths, those have hot figurative Motions, but not burning: and the moist, liquid, and wet Nature of water, makes it apt to joyn, and divide, to, and from other sorts of Motions; as also, to and from its own sort. CHAP. XVIII. The Cause of the Ebbing and Flowing of the Sea. The Nature of water is to flow; so that all sorts of waters will flow, if they be not obstructed: but it is not the Nature of Water, to ebb. Neither can water flow beyond the Power of its Quantity: for, a little water will not flow so far as a great one. But, I do not mean by flowing, the falling of water from some Descent; but, to flow upon a Level: for, as I have said, all waters do naturally flow, if they be not obstructed; but, few sorts of water, besides Sea-water, ebbs. As for the Exterior Figurative Motions of water, in the action of flowing, they are an Oval, or a half Circle, or a half Moon; where the middle parts of the half Moon, or Circle, are fuller than the two Ends. Also, the figure of a half Moon, or half Circle, is concave on the inside, and convex on the outside of the Circle: but, these Figurative Motions, in a great quantity of water, are bigg and full, which we name _Waves of Water_; which waves flowing fast upon each other, presses each other forward, until such time as the half Circle divides: for, when the Bow of the half Circle is over-bent, or stretched, it divides into the middle, which is most extended: and when a half Circle (which is a whole wave of water) is divided, the divided Parts fall equally back on each side of the flowing waves: so, every wave dividing, after that manner, in the full extension, it causes the motion of ebbing, that is, to flow back, as it flow'd forward: for, the divided Parts falling back, and joining as they meet, makes the head of the half Circle, where the Ends of the half Circle were; and the Convex, where the Concave was; by which action, the ebbing Parts are become the flowing Parts. And the reason that it ebbs and flows by degrees, is, That the flowing half Circles require so much time to be at the utmost extension. Also, every wave, or half Circle, divides not all at one time, but one after another: for, two Bodies cannot be in one place at one point of time; and until the second, third, and so the rest, flow as far as the first, they are not at their full extension. And thus the Sea, or such a great Body of Water, must flow, and ebb, as