“The commencement of the rainy season was a warning to all the Arabs of this country, who were preparing for their annual migration to the sandy and firm desert on the west bank of the river, at Gozerajup; that region, so barren and desolate during the hot season, would shortly be covered with a delicate grass about eighteen inches high. At that favoured spot the rains fell with less violence, and it formed a nucleus for the general gathering of the people with their flocks. “The burning sun, that for nine months had scorched the earth, was veiled by passing clouds; the cattle that had panted for water, and whose food was withered straw, were filled with juicy fodder; the camels that had subsisted upon the dried and leafless twigs and branches, now feasted upon the succulent tops of the mimosas. Throngs of women and children mounted upon camels, protected by the peculiar gaudy saddle hood, ornamented with cowrie shells, accompanied the march: thousands of sheep and goats, driven by Arab boys, were straggling in all directions; baggage-camels, heavily laden with the quaint household gods, blocked up the way; and fine bronzed figures of Arabs, with sword and shield, and white topes or plaids, guided their milk-white dromedaries through the confused throng with the usual placid dignity of their race, simply passing by with the usual greeting, ‘_Salaam Aleikum_’ (Peace be with you). “It was the Exodus; all were hurrying towards the promised land—the ‘land flowing with milk and honey,’ where men and beasts would be secure not only from the fevers of the south, but from that deadly enemy to camels and cattle, _the fly_; this terrible insect drove all before it.”[120] During the wet season the Mouderir (Government) of Kassala is transferred to new buildings which have recently been erected for its reception at the village of Goz Regeb, and there is a general movement of the Europeans and the wealthier native inhabitants of the town to the same place. The exercise of jurisdiction and the collection of revenue in this region are made difficult by the annual migration of which Sir Samuel Baker wrote. Great numbers of people from different parts of the country collect now, as in former days, within one district in a very short space of time, the comminglement of flocks and herds adds to the confusion, and it is no simple administrative task to deal with a shifting population of this magnitude. If the seroot fly were exterminated, as certain species of noxious African mosquitoes have been, this yearly exodus would no longer take place.