The Soudan is an agricultural country; in that direction alone can real progress be made, and the progress depends mainly upon irrigation. Between the Atbara and the Blue Nile, and between the Blue Nile and the White Nile, there is, as has been pointed out, a great field for irrigation works on a large scale, but the amount of crops now grown by direct irrigation is very small. Along the Blue Nile water-wheels are numerous for the first ten miles above Khartoum. There used to be 3,000 between Khartoum and Berber, but in 1898 there were no more than seventy; and though the number has increased, it has yet nothing like reached the old level. The same is true of the rest of Berber Province and of Dongola. There is also a certain amount of irrigation on islands in the White Nile above Khartoum. When the river is falling, large mud flats appear in the centre of the stream. To these the people transport their cattle and belongings; they sow their seed in the mud, build themselves huts, and set up shadoofs to water the growing crops of wheat, barley, dhurra, and onions. They begin operations towards the end of January, and in good soil the crops are harvested by May. What perennial irrigation can do is shown by the gardens at Khartoum, where lemons, figs, oranges, pomegranates, bananas, vines, and all kinds of vegetables, grow in profusion all the year round. But at present nearly all the crops are rain crops. The height to which water has to be raised out of the Blue Nile is too great for extended irrigation by mere lift. For the first 150 miles from Khartoum the banks are 26 to 30 feet over the summer level, and further south 33 to 39 feet, the difference between summer and flood level being about 23 feet. The soil of the Ghezireh is a rich alluvial deposit sometimes 150 feet deep. The inhabitants build small dykes across the general slope of the country so as to prevent the rain running off too quickly, and sow their seed as soon as the rain has fallen. The result as described by Sir R. Wingate a year or two ago is as follows: ‘I recently rode from Wad Medani on the Blue Nile to opposite Duem on the White Nile, eighty miles across a perfectly flat plain sown almost throughout its entire length with dhurra, which was standing 6 to 8 feet high. As there is only one crop sown during the short rainy season, and as this is planted and harvested within a period of sixty to eighty days, it follows that, if a system of irrigation were possible in the Ghezireh it would become a huge granary capable of supplying, not only the whole Soudan, but other countries as well.’