Page:Travels to Discover the Source of the Nile - In the Years 1768, 1769, 1770, 1771, 1772, and 1773 volume 1.djvu/555

Rh in that valley all the summer months, and is called the Etesian winds; it sweeps the valley from north to south, that being the direction of Egypt, and of the Nile, which runs through the midst of it. The two chains of mountains, which confine Egypt on the east and on the west, constrain the wind to take this precise direction.

is natural to suppose the same would be the case in the Arabian Gulf, had that narrow sea been in a direction parallel to the land of Egypt, or due north and south. The Arabian Gulf, however, or what we call the Red Sea, lies from nearly north-west to south-east, from Suez to Mocha. It then turns nearly east and west till it joins the Indian Ocean at the Straits of Babelmandeb, as we have already said, and may be further seen by consulting the map. Now, the Etesian winds, which are due north in Egypt, here take the direction of the Gulf, and blow in that direction steadily all the season, while it continues north in the valley of Egypt; that is, from April to October the wind blows north-west up the Arabian Gulf towards the Straits; and, from November till March, directly contrary, down the Arabian Gulf, from the Straits of Babelmandeb to Suez and the Isthmus.

winds are by some corruptly called the trade winds; but this name given to them is a very erroneous one, and apt to confound narratives, and make them unintelligible. A trade-wind is a wind which, all the year through, blows, and has ever blown, from the same point of the horizon; such is the south-west, south of the Line, in the Indian and Pacific Ocean. On the contrary, these winds, of which we have now spoken, are called monsoons; each year they blow

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