As if to emphasize what the Doctor was saying, the train carried them past a thrashing-floor where the scriptural process of "treading out the corn" was going on. There was a floor of earth, which had been packed very hard and made smooth as possible, and on this floor the pair of oxen were walking in a circle and dragging a sort of sled, with rollers between the runners, on which a man was perched in a high chair. The straw which had been deprived of its grain was heaped in the centre of the circle, ready for removal; the Doctor explained that the grain was separated from the chaff by throwing it in the air when the wind was blowing, and such a thing as a winnowing-machine was practically unknown in Egypt. [Illustration: ANCIENT PROCESS OF TREADING OUT THE CORN.] Attempts have been made to introduce modern implements and machinery for agricultural purposes, but they have generally failed. The Khedive expended a large amount of money for the latest improvements in farming; he had a large farm near Cairo, on which the purchases were placed, but it was soon found that the implements were unpopular with the natives, and they were abandoned. They lay for some years in one of the sheds of the establishment, and were finally sold as old iron. [Illustration: EGYPTIAN LENTILS.] The sight of the ploughs, shadoofs, thrashing-machines, and other aids of agriculture naturally led to a conversation on the products of Egypt. The boys learned that two kinds of corn were grown there--doora, which they had seen, and millet, which has a single ear on the top of a stalk. Egyptian wheat has been famous for many centuries, and is still cultivated, though to a less extent than formerly, as much of the ground once devoted to wheat is now given up to cotton. Coffee is grown in some localities, and so are indigo and sugar; there is a goodly variety of beans, peas, lentils, and the like, and watermelons, onions, and cucumbers are easily raised. The tobacco crop is of considerable value; grapes are abundant, and there are many fruits, including dates, figs, apricots, oranges, peaches, lemons, bananas, and olives. The methods of agriculture are very primitive, and in many instances slovenly; and if a thousand English or American farmers could be sent to Egypt to instruct the natives in the use of foreign implements, and teach them to till their farms on the Western plan, the value of Egyptian products would be doubled. But, to make the plan successful, it would be necessary to devise some means of compelling the natives to use the methods and machines that the strangers would bring among them, and this would be a difficult task. The train halted several times, and finally came to Kallioob station, where it united with the direct line from Cairo to Alexandria. "Now," said the Doctor, "keep a sharp lookout on the right-hand side of the carriage and tell me what you see." In a few minutes Frank gave a shout of delight, and called out,