[Footnote 9: ‘Zeitschrift der Gesellschaft für Erdkunde zu Berlin,’ 1902, Tafel III.] [Footnote 10: ‘Topography and Geology of the Fayum Province of Egypt’ (Cairo, 1905), p. 67.] [Footnote 11: Since the above was written, the Professor of Geography at the new University of Cairo, M. Lorin, has suggested that at a former geological epoch the Nile flowed through Siwa Oasis and thence westward so as to make Cyrenaica an island. (See ‘L’Egypte,’ published by the Institut Français d’Archéologie Orientale, Cairo, in December 1926, p. 153.) M. Lorin does not give any grounds for this suggestion, and I know of no evidence that would justify its acceptance. As will be gathered from my remarks elsewhere in this paper, it seems to me far more likely that Siwa and the other northern depressions were in recent geological times regions of central drainage, than that they were local deepenings of a single channel; and in regard to earlier geological periods we possess too little information to form any conclusions as to drainage- lines.] [Footnote 12: See Sir Hanbury Brown’s ‘The Fayum and Lake Moeris’ (London, 1892), pp. 40-48 and 106-110; Sir W. Willcocks’ ‘Perennial Irrigation and Flood Protection for Egypt’ (Cairo, 1894), also the same author’s ‘Egyptian Irrigation,’ third edition (London, 1913); Sir W. E. Garstin’s ‘Report on the Basin of the Upper Nile’ (Cairo, 1904), Appendix I. pp. 6-9; and Beadnell’s ‘Topography and Geology of the Fayum Province of Egypt’ (Cairo, 1905), pp. 16-24.] [Footnote 13: ‘Report on the Administration of the Irrigation Department for 1895’ (Cairo, 1896), pp. 25-28.] [Footnote 14: ‘Report on the Administration of the Irrigation Department for 1896’ (Cairo, 1897), p. 129.] [Footnote 15: It may be remarked that even if a channel were to be cut from Lake Mariut to the Wadi Natrun it would still be necessary to continue pumping on a large scale from Lake Mariut to maintain the present-day drainage. According to returns communicated to me by the Irrigation Service, the quantity of water removed from Lake Mariut by pumping during the last nine years has averaged nearly 650 million cubic metres a year; and even on the most optimistic estimate of evaporation and seepage the Wadi Natrun could not be expected to dispose of half this quantity after the lapse of the few years which would be occupied in filling it to a permanent level.] [Footnote 16: The average discharge of the Nile past Cairo in a year is 67 cubic kilometres. The capacity of the Qattara depression at the sea- level contour is roughly about 900 cubic kilometres.] [Footnote 17: _Geogr. Journ._, 56 (1920), pp. 97-99 and 161-163.]