* Dark monsoon inshrouds. l. 129. When from any peculiar situations of land in respect to sea the tropic becomes more heated, when the sun is vertical over it, than the line, the periodical winds called monsoons are produced, and these are attended by rainy seasons; for as the air at the tropic is now more heated than at the line it ascends by decrease of its specific gravity, and floods of air rush in both from the South West and North East, and these being one warmer than the other the rain is precipitated by their mixture as observed by Dr. Hutton. See additional notes, No. XXV. All late travellers have as∣cribed 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.

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