Page:Philosophical Transactions - Volume 001.djvu/264

 the Niter, which the Nile is stored with, is the cause of all these strange effects, and of many others, by him alledged, For, saith he, when the Nitre is heated by the heat of the Sun, it ferments, and mingling with the water, troubles it, and swells it, and makes it pass beyond its banks; after the same manner, as the Spirits in new Wine render it troubled, and make it boyle in the vessel. And it seems not likely to him, that the Mud, found in the Nile, should come a far off; for then it would at last so raise the banks of this River, that it would not be able to overflow them any longer, Whereas 'tis more than 2000 years, that the banks thereof are not grown higher, there being now requisite but 16. cubits for overflowing the Land, no more than there was in the time of Herodotus. Which shews, saith he, that this Mud is nothing but a volatil Niter, which exhaling, doth not increase the Earth. As for the Ægyptian Dew, and the increase of the weight of the Mud, he adscribes them to the same Cause. For, the spirits of Nitre abounding in the Nile, when raised into the Air with the vapors, that exhale continually from this River, there is made out of their mixture, a Dew, that refreshes the Air, makes sickness to cease, and produces all those admirable effects, that make the Ægyptians wish for it so passionately. And the same spirits of Niter, being joyned to the Paste, and to the Mud, raise the one, and augment the weight of the other. That, which Mr. Buratini observes, that at the time of this inundation, the Niter-pits of the neighbouring places vomit out liquid Niter, and that one may see issue out of the Earth abundance of Chrystals of Nitre, is alledged to fortify this conjecture; Which is yet more confirm'd by the Fertility, communicated to the Earth by the Mud of this River. For, plants do grow there in such abundance, that they would choak one another, if it were not remedied by throwing Sand upon the Fields; insomuch that the Ægyptians must take as much pains to spread Sand to lessen the fatness of their Land, as other Nations do, to spread dung or other manure upon theirs to increase the fatnes.

In the Fourth and Fifth, the Author undertakes to prove, that all those strange effects cannot be attributed to Rain or Snow, Rh