LIMITS AND EXTENT descriptions of it from merchants or the leaders of raiding expeditions, or from stray travellers who had visited certain portions of it. That the Arabs believed the Sudan to be an immense region is evident from a tradition quoted by Masudi (cap.

xvi.) to the effect that it required at least seven years to travel all over the Sudan and Abyssinia, that the Sudan was sixty times as large as Egypt, and that it represented one-sixtieth part of the earth's surface. From a practical point of view this tradition is of no value, for it is, clearly, one of the artificial calculations which the Arab writers rejoiced in, but it proves that the Arabs believed the Sudan to be an immense country, and they probably included in it a number of the provinces which lie to the west of Dar Fur, and a large portion of sub-tropical Africa. For the purpose of this book the Sudan means the country which is ruled by Great Britain and Egypt, and which extends from Abu Simbel, or let us say, Wadi Haifa, on the north to Gondokoro on the south, i.e., a distance of about 1,200 miles as the crow flies, and from the frontier of Dar Fur on the west to the Abyssinian frontier on the east, i.e., a distance of about 1,000 miles ; thus the Sudan may be said to cover an area of about 1,250,000 square miles, and to include the greater part of the Nile valley. Scattered over this vast extent_oiL-€etHvfery numberless tribes have liyed from Jjme imrnemoriaJj_aiid_ajnongJiiesg._dier have alwaysJaesmepresentatives oialFthejQOst impal:talItJlegroeq2lesJ:£-£ast-Afca-.

The most important natural feature of the Sudan_Js_tlie_Nile, and, in the brief account of Jhe history of the country which is givn in the- following pages, it will be seen that the rivejr has always been_thehighway by . which civilization has made its way from north to south, and that all the kingdoms which have sprung up and flourished in the Sudan during the past 4,000 years have owed their success to the fact that they were situated on the Nile, or on one of its main tributaries or branches. A glance at the map of north-east Africa will show the reader that the greater part of the Sudan consists of deserts, wherein men may travel from north to south for a month at a time without seeing a town, or even village of any size. These deserts are ribbed with apparentl}' interminable ranges of low hills of sandstone, of bare and forbidding aspect, and many thousands of square miles of territory are covered with nothing but sand, out 507 Y