404 „ ECONOMIC GEOGRAPHY
Cotton and woollen goods, chemicals, iron and steel, machinery,
fertilizers, and coal are the principal imports. Average imports,
1934-35, ££30,700,000; exports, ££32,600,000 (£E1 = £1).
THE ANGLO-EGYPTIAN SUDAN
The Sudan, which is under the joint control of Great Britain
and Egypt, has an area of about 1,000,000 square miles. Its
population, which is now over 6,300,000, at one time numbered
9,000,000, but was reduced during the Dervish tyranny to less
than 2,000,000. -
The climate varies greatly from one region to another. Except
along the Red Sea littoral south of Suakin, rain seldom falls
north of the 17th parallel, but south of it there is a gradual
increase both towards the Equator and towards Abyssinia,
Over a great part of the basin of the Bahr el Ghazal, and of the
country between the Bahr el Jebel and the Sobat, there is a mean
annual rainfall from 30 to 40 inches ; and in the extreme south,
where there is a double rainy season, the amount received is still
greater. The mean temperature is generally high. Such observa-
tions as have yet been made seem to indicate that at Berber it
varies from 67° F. in January to 94° F. in June ; at Khartoum from
69° F. in January to 92° F. in May ; and at Mongolia from 77° F.
in July to 82° F. in January.
The natural regions of the country may most conveniently be
studied by observing the relation *of vegetation to rainfall. To
the north of the 17th parallel, desert conditions prevail except
along the banks of the Nile, where there is a riverain population
engaged in agriculture ; in a few oases scattered here and there ;
and in some districts south of Suakin, where cultivation is possible
on land which is annually inundated by rivers in flood, as at Tokar
and Kassala where much cotton is grown. The date-palm is the
chief asset of all this region.
South of the rainless area there lies a belt of country which, as
regards its vegetation, is transitional between the desert to the
north and the true savanna to. the south. The northern parts
consist, in the main, of poor scrub-land, on which camels, goats,
and sheep are raised, but farther south there are forests of acacia
and large areas of grassland, where in years of good rainfall a
considerable amount of agriculture is possible. Dura (Sorghum