valley, about a degree south of the latitude of Memphis—­a depression of great depth and of ample expanse, fifty miles or more in length by thirty in breadth, and containing an area of six or seven hundred square miles.  It was separated from the Nile valley by a narrow ridge of hills about two hundred feet high, through which ran from south-east to north-west a narrow rocky gorge, giving access to the depression.  It is possible that in very high floods some of the water of the inundation passed naturally into the basin through this gorge; but whether this were so or no, it was plain that by the employment of no very large amount of labour a canal or cutting might be carried along the gorge, and the Nile water given free access into the depression, not only in very high floods, but annually when the inundation reached a certain moderate height.  This is, accordingly, what Amenemhat did.  He dug a canal from the western branch of the Nile—­the modern Bahr Yousuf—­leaving it at El-Lahoun, carried his canal through the gorge, in places cutting deep into its rocky bottom, and by a system of sluices and flood-gates retained such an absolute control over the water that he could either admit or exclude the inundation at his will, as it rose; and when it fell, could either allow the water that had flowed in to return, or imprison it and keep it back.  Within the gorge he had thus at all times a copious store of the invaluable fluid, banked up to the height of high Nile, and capable of being applied to purposes of cultivation both within and without the depression by the opening and shutting of the sluices.

So much appears to be certain.  The exact size and position of Amenemhat’s reservoir within the depression, which a French savant was supposed to have discovered, are now called in question, and must be admitted to be still sub judice.  M. Linant de Bellefonds regarded the reservoir as occupying the south-eastern or upper portion of the depression only, as extending from north to south a distance of fourteen miles only, and from east to west a distance varying from six to eleven miles.  He regarded it as artificially confined towards the west and north by two long lines of embankment, which he considered that he had traced, and gave the area of the lake as four hundred and five millions of square metres, or about four hundred and eighty millions of square yards.  Mr. Cope Whitehouse believes that the water was freely admitted into the whole of the depression, which it filled, with the exception of certain parts, which stood up out of the water as islands, from one hundred and fifty to two hundred feet high.  He believes that it was in places three hundred feet deep, and that the circuit of its shores was from three hundred to five hundred miles.  It is to be hoped that a scientific expedition will ere long set this dispute at rest, and enable the modern student distinctly to grasp and understand the great work of Amenemhat.  Whatever may be the truth regarding