Page:Africa by Élisée Reclus, Volume 1.djvu/413

 RAlXFAIJi. 888 had turnwl southwards, and wa« now travelling over the dcaert away from iw, I earnestly hoped, to expend itself in space before meeting with any unfortunate victims. Inexpressibly thankful was I as we entered the town, for I could not but fiH'l that it had perhaps been a race for Kfo. It was now over and we were safe ; but it was several hours, or I may more truly say days, before the effect on my overstnmg nerves passed entirely away." * On an average, northern breezes are six times more frequent at Cairo than those from the south. But as we ascend the Nile and approach the equatorial regions the equilibrium tends to be established between the conflicting currents, and in Nubia the northern or winter are about fairly balanced with the southern or summer winds. Rainfall. The region of the Egyptian delta is comprised within the Mediterranean climatic zone. Winter arid summer here succeed each other as in Southern Europe, the only difference being that the intermediate seasons of spring and autumn are reduced to much narrower limits.! The Egyptian summer, during which the Nile waters rise and spread over the land, is accompanied by the clearest skies ; yet the atmosphere is then heavily charged with moisture, often almost to the point of saturation. On the Red Sea coast especially, the traveller finds himself at times enveloped as in a vapour bath. Winter is the rainy season, but it is seldom attended by much humidity, although in the lower delta the rainfall often suffices to interrupt the communica- tions. The banks of the canals, here the only highways, are changed by the slightest showers into quagmires of treacherous and slippery mud. Even in Alexandria, lying as it does within the influence of the moisture-bearing clouds from the Mediterranean, the mean annual rainfall is only 7 inches according to Russegger, or 8 inches according to more recent observers ; that is to say, one-third of the quantity received by Paris, and one- fifth of the average for the whole of France.* At Cairo, where the marine vapours arrive already deprived of much of their humidity, the mean discharge is much less, amounting to no more than about 1| inch, or the fiftieth part of the discharge at Cherra-Ponji in British India. The ancient Egj-ptians called themselves the inhabitants of the "Pure Region." Nevertheless the sky is overcast at Cairo for over three months in the year, and at times the downpours have been heavy enough to flood the streets. In 1824, and again in 1845, several houses were destroyed by these sudden freshets. In the Arabian and Libyan deserts south of the delta, the rains are still lighter, although not altogether unknown, as is so often asserted. Tremendous discharges • " Wanderings in the Sudan," vol. ii., p. 260. t Mean temperature of Egypt. Alexandria, 68' F. Cairo, 70 F. Toil Said, 7 1* F. „ „ in August (hottest month) „ 79* F. „ 86* F. „ „ in January (coldest month) „ 64' F. „ 60" P. Higheat recorded „ lU'F. „ 116« F. X Mean fi|maal rainfall at Alexandria from 1873 to 1881, 8-6 ische*.