Weeks together, store of Rain, as the_ Abyssins _themselves have related at_ Grand Cairo, _which may likewise be confirm’d by_ Josephus Acosta, _Lib._ 1. De naturâ Orbis novi, _where he observes, that in_ Peru _and some other Places, lying in the same Paralel with_ Æthiopia, _they have abundance of Rain. [Sidenote: Cause of the Inundation of _Nile_.] This then is the true Cause of the Inundation of_ Nile _in the Summer-Time, it being then highest when other Rivers are lowest, and not those which are alledg’d by_ Herodotus, Diodorus Siculus, Plutarch, Aristides, Heliodorus _and others, who are all extreamly troubl’d to give a Reason for the Inundation of this River, imputing it either to the peculiar Nature of its Water, the obstruction of it by the_ Etesiæ, _or else to the melting of the Snows in_ Æthiopia, _which however I verily believe rarely fall in those hot Countries, where the Natives, by reason of the extream Heats, are all Black, and where, if we credit_ Seneca, Argentum replumbatur, _Silver is melted by the scorching Climate, or in a word, to some other such like Reasons of small weight. In_ Diodorus Siculus _I find_ Agatharcides Cnidius _giving almost the same Reason I have done, whose Assertion however those Times gave but little credit to, yet does_ Diodorus _seem to agree with it in these words_, Lib. 1. _Agatharcides Cnidius_ has come nearest the Truth, he affirming that every Year, in the Mountains about _Æthiopia_, there are continual Rains from the Summer Solstice to the Autumnal Equinox, which cause this Inundation of _Nile_. _The Time of this is so certain, that I have known the_ Egyptian _Astronomers put down many Years before in their_ Ephemerides, That such a Day of such a Month the _Nile_ will begin to rise. Thus far _Greaves_, to which I may add an Experiment of the Lord _Bacon_’s concerning the scarcity of Rain in _Egypt_. [Sidenote: An _Experiment_ concerning the scarcity of _Rain_ in _Egypt_.] _’Tis strange_, says he, _p._ 161. _of his_ Natural History, _the River_ Nile _overflowing as it does the Country of_ Egypt, _there should nevertheless be little or no Rain known in that Country. The Cause must lye either in the Nature of the_ Water, _the_ Air, _or of both. As for the_ Water, _it may_, First, _be ascrib’d to its long Course; for swift running Waters vapour less than those that are standing, as those that have been sometimes boyling on the Fire, do not cast so great a steam as they did at first: Now ’tis certain the Waters of_ Nile _are sweeter than others in taste, and excellent good against the_ Stone _and_ Hypocondriacal Melancholy, _which shews they are_ Lenifying. Secondly, _The Reason of this Inundation may be, that these Waters running thro’ a Country of a hot_ Climate _and flat, without shade either from Woods or Hills, the_ Sun _must thereby necessarily have greater power to concoct them. As for the_ Air, _whence I conceive this want of Showers chiefly comes, the Cause must be, that