BRITISH EAST AFRICA The physical features of British East Africa present some striking contrasts. Along the coast there is a plain which, at Mombasa in the south, has a width of only two miles, but broadens out, in the neighbourhood of the Juba river in the north, to over a hundred miles. From the plain a steep ascent leads to the Nyika, as this part of the African plateau is called. Still further west, the land continues to rise to the highlands of the volcanic region, beyond which lies part of the Eritrean rift valley. On the other side of the valley, the mountains fall away to Victoria Nyanza, which is at a height of 3,726 feet above sea-level.
Over the greater part of the country, altitude is an important factor in determining climatic conditions. At Mombasa (lat. 4°4' S.) the mean temperature varies from 78.5° F. in July to 83° F. in April ; while at Machakos (lat. 1°31' N.), which is at an elevation of 5,400 feet, it ranges from 61° F. in July to 68° F. in February. At Port Florence, on Victoria Nyanza, the temperature is nearly as high as on the coast. Rainfall also varies greatly
from one place to another. On the coast, over a large part of the highland area north of Nairobi, and in the vicinity of Victoria Nyanza, there is a mean precipitation of over 40 inches. The remainder of the country has in the south from 30 to 40 inches, and in the north from 20 to 30 inches or even less. There is a double rainfall period : on the coast, the heavier rains fall from April to June, and the lighter from October to December ; in the highlands, the earlier rains last from March till the end of May, and the later from October till the end of December.
VEGETATION.—Parts of the coast and much of the Nyika have but a scanty vegetation ; there is little grass, and the surface of the land is often either bare or covered with acacia bush. The Highland region is a savanna, in which there is rich grass land, interspersed with forests according to local variations in soil and climate. The rift valley is mainly grass land.