— 20 — Crude Oil.—In a search for means of cheapening the cost of water pumped for irrigation purposes, it has been impossible to ignore the widespread adoption of the internal combustion engine, adapted to the use of crude oil. This fuel with a theoretical value of four to six times that of coal by weight, and a very low production cost, has been offered at Suez at a price of less than £3 a ton, and promised to afford a solution of the excessive water bill sustained by all estates in the Northern Sudan. Further, its transport in bulk is incomparably easier and more convenient than that of coal. Authority was consequently sought to experiment with a recent pattern of semi-Diesel engine, pending completion of current negotiations fpr the establishment of oil tanks at Port Sudan and a system of bulk carriage on the railways. Atrial shipment* of twenty-five tons of the liquid fuel was obtained duty-free from Suez, but was called upon to carry the prohibitive charges of £E.4.910 per ton for freight and handling.

Despite the excessive handicap of the transport charges imposed, the semi-Diesel engine installed at Tuti in April, 1914, furnished cheaper water to the initial trials than had been obtained by the use of any other plant. Faulty construction and material unfortunately resulted in an early loss of efficiency and ultimate breakdown, but this issue does not affect the position established for the type of fuel. Imported in bulk and employed in a reliable and efficient type of engine, its use would undoubtedly reduce the cost of agricultural production in the Northern Sudan, and widen the disappearing margin of profit, by notable figures.

Wood Fuel.—In these circumstances, it was determined to conduct a belated enquiry into the value of local wood fuel, supplies of which are adequate for any such period as is likely to elapse before the advantages of liquid fuel compel recognition of the necessity for suitable facilities. As far as can be ascertained, comparative trials of coal, liquid fuel and wood have now for the first time been locally completed in modern and efficient steam boilers, and the findings have not only afforded considerable encouragement, but have also warranted an immediate extension of our operations. Briefly, in an ordinary locomotive boiler wood has been found 46 per cent, cheaper than imported coal, and the average cost of water pumped to a mean height of 22 feet 6 inches over a season of nine months, 260 milliemes per thousand cubic metres. With a mean duty of water established as 482 milliemes, including all losses from seepage and evaporation, the average cost of irrigation per feddan amounts to 125.7 * It is regretted that the question of bulk shipments has again been allowed to fall into abeyance, while the fuel problem remains the principal obstacle to all development. It may be mentioned in this connection that a pipe line for crude oil 400 kilometres long has been laid from Matadi to Leopoldville on the Congo, by means of which our neighbouring colony will be provided with motive power for agricultural and transport enterprises and other industries which can in consequence now be established. The United States Commercial Agent recently called attention to the fact that in the Sudan "the high price of coal is creating a demand for crude-oil engines of 20 to 100 horse-power for use in driving pumps and in operating the flour mills in various parts of the country."