Page:Africa by Élisée Reclus, Volume 3.djvu/68

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WEST AFRICA.

48 WEST AFEICA. from the normal directions are very frequent in these waters, which lie in the intermediate zone between the tropical and temperate seas. Thus the north-west currents are often deflected eastwards by the neighbourhood of the Sahara, and transformed to north and north-east winds. At times also the Icsfe, as the scirocco is here called, blows from the desert towards Madeira, but it is usually very weak and seldom lasts long. The system of general currents is daily modified by the regular movement of the terral, or land-breeze, blowing from the uplands sea- wards, and of the imhate, or sea-breeze, blowing landwards. The change of direc- tion often takes place before noon, so that the greatest heat prevails in the early part of the day. The chief moisture-bearing currents are the trade winds more or less deflected and transformed to north and north-west breezes. The wettest month is December, August the driest ; but no season is quite rainless, and the rainfall varies remark- ably from year to year. On an average scarcely a hundred wet days are recorded at Funchal, which is about half that of the Azores, the quantity of rainfall being nearly in the same proportion in the two archipelagoes. According to Heineken, that of Funchal is about 30 inches yearly, so that the inhabitants of Madeira are obliged to husband their resources, utilising the water from the melting snows to irrigate the plains, and diverting the copious streams by means of Icvados, or aqueducts running in galleries through the hills and encircling the escarpments above the valleys. These springs are partly fed by the dense fogs which con- stantly settle morning and evening on the summits of the interior. Flora. Although less extensive than the Azores, the Madeira group possesses a far more varied flora, which is due no doubt to its greater proximity to the two continents of Europe and Africa, and to its milder climate favouring the development both of tropical plants and species peculiar to the temperate zone. Madeira is like a large botanical garden, in which the two floras are intermingled. To the seven hundred species supposed to have been indigenous at the arrival of the Portuguese, there have since been added thousands introduced by man either unintentionally, or designedly for agricultural, industrial, or ornamental purposes. " The violet," says Bowditch, " grows beneath the shade of the bananas ; the strawberry ripens at the foot of the mimosas; palms and conifers flourish side by side; the guava and pear- trees are met with in the same enclosures." Thanks to a few indigenous plants, and especially to the exotics introduced since the colonisation, the present vegetation of Madeira in many respects recalls that of the tropical lands in Africa and the New World, without however losing its general European aspect. Of the 700 species, of which 527 are very probably endemic, 357 belong to Europe, while not more than 30 can be referred to the tropical flora of both hemispheres. As regards the indigenous species either peculiar to Madeira or common to some of the other Atlantic archipelagoes, Madeira shows the greatest resemblance to the Canary group. Hence Webb, Ball, and other naturaHsts have