being its nature to flow; and the flowing Figure, being over-extended, by endeavouring to flow beyond its power, causes a dividing of the Extended Parts, which is the Cause of the Ebbing. But, whether this Opinion of mine, be as probable as any of the former Opinions concerning the Ebbing and Flowing of the Sea, I cannot judg: but I would not be mistaken; for the flowing of the water, is according to its Quantity; for, the further it flows, the fainter, or weaker it is. CHAP. XIX. Of OVERFLOWS. As for _Overflows_, there be many; and many more would be, if the waters were not hindred and obstructed by Man's Inventions. But, some Overflows are very Uncertain and Irregular; others, Certain and Regular, as, the flowing of _Nilus_ in _Egypt_: but as for the distance of time of its flowing, it may proceed from the far Journey of those flowing-waters: and, the time of its ebbing, may be attributed to the great Quantity of Water; so that the great quantity of water, will cause a longer or a shorter time in the flowing or ebbing; and certainly the waters are as long a flowing back, as flowing forward. As for Spring Tides, they are only in such a time when there is a Naturall Issue of a greater quantity of water: so that Spring-Tides are but once a Month, and Single-Tides in so many hours: but, many several occasions, may make the Tides to be more or less full. As for Double-Tides, they are occasioned through the Irregular dividing of the Half-Circle; as, when they divide not orderly, but faster than they orderly should do; which, falling back in a Crowd, and being, by that means, obstructed, so that they cannot get forward, they are necessitated to flow, where they ebb'd. The reason the Tides flow through Streams of Running-waters, is, That the Tide is stronger than the Stream: but, if the Stream and Tides pass through each other, then the Tide and Stream are somewhat like Duellers together, which make Passes and Passages for their conveniency. CHAP. XX. Of the Figure of Ice and Snow.