AFRICA 



Climate. North America stretches from well 

 within the tropics to the Arctic Circle, and in 

 consequence has a climate which runs through 

 all degrees from torrid to frigid. Africa, on the 

 other hand, lies almost wholly within the 

 tropics, and has therefore a much more even 

 temperature. And that temperature is almost 

 uniformly high, for cooling sea breezes are shut 

 out by the steep edges of the plateaus which 

 everywhere border the coast. The variation in 

 temperature throughout the year is not more 

 than 20, while North America has in many 

 places a range three times that great. The 

 extreme southern part of the continent is the 

 only region which has not a tropical climate, 

 though there are places farther north where 

 unusual elevation assures pleasant climatic con- 

 ditions. 



Africa is deficient in rainfall, except in the 

 regions bordering the equator. Here there are 

 two seasons of especially heavy rainfall, though 

 there is considerable rain every month in the 

 year. Northward and southward from this 

 belt it diminishes 

 rapidly, and over 

 portions of the 

 Sahara no rain 

 ever falls. In the 

 south, too, there 

 is a stretch of 

 desert land, the 

 Kalahari, but this 

 is not so dry as 

 the Sahara, hav- 

 ing enough mois- 

 ture to make it a 

 profitable grazing 



country. To the north of the Sahara and south 

 of the Kalahari there is one rainy season during 

 the year, and agriculture may be successfully 

 practised. The surface structure of the conti- 

 nent has as much to do with its lack of rainfall 

 as with its temperature, for moisture-bearing 

 winds do not reach the interior. Indeed, so 

 dry and hot are the winds which blow over 

 parts of the continent that they absorb the 

 moisture from the lands over which they pass 

 and make them yet more arid. 



The highest parts of the plateaus of Africa, 

 as well as the more temperate northern and 

 southern portions, are healthful for Europeans 

 as well as for the natives; but the damp equa- 

 torial regions abound in fevers and are con- 

 sidered the most unhealthful places in the 

 world. Even the natives in these parts are 

 short-lived, for the fevers attack them as well 



Over 120 

 60-l20in. 

 20-60 - 

 10-20" 

 Less than 

 10 in 



RAINFALL CHART 



Forest 

 Savanna 

 Steppe 

 Desert 



78 AFRICA 



as the newcomers. In a few places improved 

 sanitation has been introduced since the com- 

 ing of the Europeans, and the result has been 

 a markedly lower death rate. 



Vegetable Life. The above account of the 

 climate and rainfall tells the story of the 

 vegetation as well. North of the Atlas Moun- 

 tains conditions are much like those of South- 

 ern Europe, and 

 the oak, olive, 

 semi - tropical 

 fruits, and grains 

 flourish. In Al- 

 geria and Tunis 

 wheat is success- 

 fully raised, and 

 Morocco has a 

 region which of- 

 fers like possibili- 

 ties. In the time 

 of the Roman 

 occupation, AFRICAN PHYSICAL MAP 



i_ t IL *< Showing vegetation zones, 

 before the Chris- 

 tian era, this northern belt was the granary of 

 the world. 



South of the Atlas the slope is abrupt to the 

 Sahara Desert, where the sandy, salty soil 

 affords life to little except a few thorny shrubs. 

 In the oasis, however, where buried springs 

 come to the surface, there is a pleasing con- 

 trast, for grass, date palms and grain clothe 

 the surface with green (see OASIS). To the 

 south of the Sahara, as well as in the more 

 southerly parts of the continent where there is 

 one rainy season a year, lie the great savannas, 

 or prairies, where grass grows luxuriantly and 

 the baobab tree flourishes. It is on these 

 savannas that the farms, whether for cattle and 

 sheep or for ostriches, have been established. 

 The temperate region of the south has many 

 trees and flowers which grow nowhere else, for 

 the Sahara Desert, stretching from sea to sea, 

 is a barrier that cannot be crossed by plant 

 forms. 



Throughout most of the equatorial region, 

 where rainfall is plentiful, there is a dense 

 tropical forest. No other forests except those 

 of the Amazon equal in size, in density, and in 

 variety of trees that which extends almost 

 across Central Africa. The vines and under- 

 brush are so luxuriant that throughout much 

 of this vast extent the sun seldom if ever 

 penetrates to the ground. No one can even 

 begin to estimate the wealth in timber, vege- 

 table oils and other plant products hidden in 

 this forest of giant trees. 



