Sir HARRY JOHNSTON: I had the honour some years ago, just after the war had started, of showing you a somewhat similar map of Africa with railways designed on it partly by my own fancy, and I may say to a great extent by following French fancies too; for about that time I had been in the north of Africa, and had been allowed to pursue for a certain distance the tracing of the projected trans-Saharan railway, the progress of which was only stopped by the war. I conceived then the idea that it was of the highest importance to Western Europe that that line should be made, though I, like most of you, did not appreciate the influence on affairs that the submarine would have; but of course that conviction has been strengthened by the events of the war. Had we had the trans-Saharan railway in existence during the war we should not have suffered as much as we did from the loss of some of the most important materials for our industries caused by the interruptions of the sea routes, the destruction of steamers, etc. It is a matter of absolute necessity, I consider, that that trans-Saharan line should be made to link up the valley of the Niger with French North Africa, and further with Western Europe; because, as Colonel Tilho has pointed out, the channel between Tangier and the Spanish coast could be easily patrolled and kept free of submarines, and even crossed by train ferries. Then another point I should like to raise is as to the further exploration of those Tibesti highlands and the lofty plateaus that are connected with them on the north-west and south-east. Colonel Tilho did not mention in his discourse what he said to me privately, that he had found in some parts of that region, possibly Borku, fossilized bones of elephants. He has referred to the native legends and to the drawings on the rocks which point to the existence of hippopotami in regions now entirely devoid of surface water. He showed some of these engravings. They are very similar to rock drawings which can be traced right across the Sahara desert, exhibiting a fauna now completely passed away. One reason why Tibesti should be explored is, that we might find there the fossil and semi-fossil remains of a very extensive tropical African fauna, because that isthmus of high land between the south of Tunis on the north, and Darfur and the regions round Lake Chad on the south, seems to have been the principal route by which the fauna of Miocene and Pliocene Europe and the Mediterranean basin reached Tropical Africa. There are more and more indications that the Sahara desert to the west and the Libyan and Nubian deserts to the east were formerly under water, and therefore checked the progress of beasts and man across the Sahara into Central Africa; but this high ridge always remained well above the limits of such lakes, marshes, or inland seas. Tibesti was a well- watered region with at one time quite a heavy rainfall down to about twenty thousand years ago.