Page:Africa by Élisée Reclus, Volume 2.djvu/95

 FLORA OF FEZZAN. 75 radiation of heat into space. Still the sky is seldom perfectly cloudless, the lovely u/ure of temperate zones being here replaced by milky white tints and the striated cirri of the upper atmospheric regions. In December, and during the first half of January, the thermometer at sunrise seldom rises above 42^ or 43" F., and in many parts of the plateau water often freezes at night. Snow is even said to have been observed on the mountains encircling the country. On the other hand, the excessive heat is almost intolerable for strangers. If, according to Lyon, the summer average is already 90° F. at Murzuk, Duveyrier here twice recorded in July a temperature of 110° F. in the shade, while in the desert, properly so called, the glass often rises to over 121^ F. In the sun it exceeds 170° and even 187° F. Altogether Fezzan belongs to the climatic zone of the Sahara, in which the extremes of temperature suffice, in the language of Herodotus, to consume the very heart of the country. Where are the rocks capable of resisting the expansions and contractions caused by extremes of heat and cold, whose mean annual discrepancy amounts to 198°, and possibly even 208° F. ? The rainfall also is all the lighter in Fezzan, that the moisture-bearing clouds from the north are arrested by the Jebel-es-Soda and Black Ilaruj ranges. There id even a complete absence of dew, owing to the dryness of the air. Yet, strange to say, the inhabitants of the country do not themselves desire rainy weather, not only because it washes away thoir earthern cabins, but also on account of its injurious effects on the palm-trees, by interfering with the normal system of irrigation from the subterranean supplies. "Rain water is death, underground water is quickening," says the native proverb. Heavy showers fall usually in winter and spring, that is, from December to April, when the northern winds contend for the supremacy with those from the south. Flora of Fezzan. The great extremes of heat and cold have as their natural accompaniment a correspondingly impoverished flora. Plants unable to adapt themselves to the severe colds and intense heats, all alike perish in this climate. Even in the sheltered depressions of the desert there are scarcely any spontaneous growths, beyond a few talha acacias of scanty foliage, pale tamarisks, the thorny alhagi, on which the camel browses, the sandy colocynth, alfa grass, some scrub, a species of salsola, and two or three herbs. The cultivated are perhaps more numerous than the wild species, although in many of the gardens of the oases there is a great lack of variety. In some of the wadies are grown wheat, barley, and several other kinds of cereals, the gombo, whose pulpy fruit is highly appreciated by the Arabs, some thirty species of vegetables enumerated by Nachtigal, amongs'i which are comprised nearly all those growing in European gardens. The fig and almond yield excellent fruit, but most of the other fruit-trees of the temperate zone are rare, or represented only by a few stunted specimens. The olive reaches no farther south than the Wady Otba, to the west of Murzuk. Tobacco, cotton, and indigo flourish in the gardens of Fezzan, but the supply is