Tarantulas, scorpions, serpents, white ants, mosquitoes, and every kind of loathsome creature that flies and crawls is to be found there. When men are toiling through that land, dust in their throats, sand in their eyes, and longing with all their hearts for the sight of something green, and the touch and taste of fresh, cool, sparkling water, sometimes they see a great wonder. In front of them suddenly appears a lake or river, sparkling and shimmering. There is green grass at the water-side. White-winged birds float on it, and trees dip their leafy branches into its coolness. Sometimes great palaces and towers overlook it. Sometimes it seems a lonely spot, quiet and peaceful, and delicious for the weary wanderers to rest at. English soldiers have often started off running with their empty water-bottles to fill them in that lake or river. Many, many travellers have hastened towards it when they knew that they must have water or die. But ever the mirage, as it is called, retreats before them. That water is like magic water that no human being can ever drink. The palaces and towers are like fairy palaces and towers into which no real person ever enters. The green leaves and white birds, the trees and the grass, are only a picture that the sun and the desert make to madden thirst-parched men. "When Allah made the Soudan," say the Arabs, "he laughed." European traders were amongst the first to open a way into the Soudan. The Egyptians knew that there was much fine ivory to be got there, but were too lazy to try to get it. The Europeans, many of them Englishmen, braved dangers and hardships, and made much money by the ivory they bought from the black people of the desert land. Soon they found there was something else for which they could get much higher prices than any that they could get for elephants' tusks. They called it "black ivory." By that they meant slaves. At once they began to raid, to harry, and to kidnap the black races of the Soudan. They built forts and garrisoned them with Arabs, to whom no cruelty was too frightful, no wickedness too great. They burned down the villages of the blacks. They stole their flocks and herds. They burned or stole their crops. Their wives and little children they tore from them, chained them in gangs, and took them across the desert to sell for slaves. The men whom they could not take they slew. So great and shameless became this trade, that at last Europe grew ashamed that any of her people should be guilty of it. There was an outcry made. The Europeans sold their stations to the Arabs, and quietly withdrew. The Arabs then agreed to pay a tax to the Egyptian Government, which saw no harm in stealing people and selling them as slaves, so long as some of the money thus gained went into the royal treasury.