notes, No. XXV. All late travellers have ascribed the rise of the Nile
to the monsoons which deluge Nubia and Abyssinia with rain. The whirling
of the ascending air was even seen by Mr. Bruce in Abyssinia; he says,
"every morning a small cloud began to whirl round, and presently after
the whole heavens became covered with clouds," by this vortex of
ascending air the N.E. winds and the S.W. winds, which flow in to supply
the place of the ascending column, became mixed more rapidly and
deposited their rain in greater abundance.

Mr. Volney observes that the time of the rising of the Nile commences
about the 19th of June, and that Abyssinia and the adjacent parts of
Africa are deluged with rain in May, June, and July, and produce a mass
of water which is three months in draining off. The Abbe Le Pluche
observes that as Sirius, or the dog-star, rose at the time of the
commencement of the flood its rising was watched by the astronomers, and
notice given of the approach of inundation by hanging the figure of
Anubis, which was that of a man with a dog's head, upon all their
temples. Histoire de Ciel.]

[Illustration: Fertilization of Egypt.]

[_Egypt's shower-less lands_. l. 138. There seem to be two situations
which may be conceived to be exempted from rain falling upon them, one
where the constant trade-winds meet beneath the line, for here two
regions of warm air are mixed together, and thence do not seem to have
any cause to precipitate their vapour; and the other is, where the winds
are brought from colder climates and become warmer by their contact with
the earth of a warmer one. Thus Lower Egypt is a flat country warmed by
the sun more than the higher lands of one side of it, and than the
Mediterranean on the other; and hence the winds which blow over it