LINANT’S OBJECTIONS TO THEORY FAVOURED.

Author’s Views of Lake Mœris generally stated.—I myself agree with those who are of opinion that the Fayûm Province, or depression, (including the Gharaq Basin and the neck from Lahûn to Hawârah), was by itself Lake Mœris, and that within its limits and along its borders was to be found the inhabited and cultivated region known as the Arsinoïte Nome, which possibly also extended into the Nile Valley along the course of the canal connecting the Nile with the lake.

The Fayûm then in its submerged state was, I believe, the Lake Mœris of Herodotus, Strabo, Diodorus, and Pliny, the modern Lake Qurûn being the persistent rudiment of this lake, and all that now remains of its formerly extensive sheet of water. (See [Plate XX.])

Objections urged by Linant against these views.—This is no new theory. It is found passim before Linant Pasha in 1842 took great pains to point out its absurdity, but it was his own assumptions regarding the maximum height which the water surface of Lake Qurûn could have reached, that created the absurdity. Assuming without evidence that the villages on the second plateau were all in existence at the time of Lake Mœris, he limits the level of Lake Qurûn to the edge of the second plateau, which is the same thing as laying down that its water surface never rose above R.L. + 10·00.

Having come to this conclusion, he might have spared himself all his arguments against the theory, other than that which pointed out that a reservoir in the Fayûm at this level could have been of no utility in supplementing the low waters of the Nile.

It is, however, instructive to note how he deals with the arguments against this lake, which his imagination set bounds to, being Lake Mœris. After a separate review of each condition which Lake Mœris should fulfil and which the limited Lake Qurûn did not, he closes his reviews with the remark that “we may then conclude that Birket-el-Qurûn is not the Lake Mœris.” But he does not do so always. Should the condition be one with which his own theory is not in agreement, he explains it away or discredits it. The dimensions assigned to Lake Mœris by the ancient historians evidently trouble him, and he does his best to discredit their testimony on this point. After discussing this condition, he does not end his argument with the usual conclusion that “the present Lake Qurûn cannot be Lake Mœris,” but he says “an absolute importance must not be attached to all these measures in order to draw from them conclusions either positive or negative as to the identity of the position of Birket-el-Qurûn with that of the ancient Lake Mœris.”

The depth assigned to Lake Mœris also gives rise to the following remarks, which will afford the means of judging of the value of M. Linant’s arguments. He states that Herodotus gives the depth of the lake at 92 metres, and remarks that if the whole Fayûm had been filled to form the lake, its dimensions would have surpassed by ten times the greatest given for it.

But as a matter of fact, they do not even come up to the greatest dimensions given, which are, for the depth 92 metres, and for the perimeter of the lake 720 kilometres (450 miles), or, assuming as he does that Herodotus made use of the small stadius, 360 kilometres. Now the perimeter of the Fayûm is 220 kilometres, and if that of the Wadi Raiân is added, namely 200 kilometres, the total perimeter becomes 420 and that figure is only obtained by measuring the indentations of the Wadi Raiân, which is of a peculiar shape.

The depth of the Fayûm Lake, if filled to say R.L. + 25·00, would be not less than (25·00 + 43·50 + 5·00 =) 73·50 metres, nor more than 88·00 at the highest estimate.

These dimensions agree approximately with those given by Herodotus, and are not, as rashly stated by Linant, ten times in excess.

To show with what unfairness Linant deals with statements made by Herodotus, his arguments about the bricks made for the pyramid built by Asychis may be noted. It was stated that the bricks were made from mud brought up from the bottom of the lake. Linant claims this statement as supporting his theory, as his lake was a shallow one, and as opposing the enlarged Lake Qurûn theory, as this latter would be a deep one. It does not seem to strike him that the workmen could have sought their mud along the shallow margins of the larger lake. He further argues that one could not reach down more than 4 metres with poles, and therefore the lake could not have been so deep as stated by Herodotus, and hence Herodotus contradicts himself! But Herodotus did not say that the lake was 92 metres deep all over, and that its shores were not shallow, but that its greatest depth was 92 metres.

Linant Pasha discussed the possibility of the submerged Fayûm being the Lake Mœris, but rejected the idea, because, to fulfil the condition of supplementing the low Nile, the water must have covered the second plateau, and risen to a level above the rock sill at Hawârah (R.L. 21·00). “Then,” he points out, “the whole Fayûm would have been only a vast lake and with a height of water impossible to reconcile with the existence of large towns, which formed the rich Crocodilopolite or Arsinoïte nomes. The great quantity of ruined towns, abandoned like Medinet-el-Mahdi, Medinet-el-Hêb, Medinet Nemroud, Kasr Keroun, indicate, as well as those which still exist, as Sanuris, Sanhur and all the others, that this part has never been under water, and they date from the time of Lake Mœris and of Crocodilopolis.” (Earlier in his book he states about Kasr Keroun, “Kasr Keroun is a little monument, quite modern as compared with the epoch of the Labyrinth.” Mr. Petrie and Dr. Schweinfurth both state that Qasr Qurûn is a Roman temple or town.) M. Linant continues, “If ever the Fayûm has been under water, as we have supposed it, it was long before it was habitable and before the Lake Mœris existed.”

Plate XIV.

OLD BUILDING ON NORTH SIDE OF LAKE QURÛN,

DISCOVERED BY DR. SCHWEINFURTH IN 1884. EXTERIOR FROM NORTH-EAST.

Now as regards the modern villages of Sanûris, Sanhûr, and others, I am not aware on what evidence M. Linant states that they existed at the same time as Lake Mœris. As regards the old abandoned towns mentioned, some of them are on elevated spots, and probably were on the shores of Lake Mœris. When Lake Mœris declined and the water had receded to a distance from them, they were abandoned for more favourable sites, less remote from a water supply and water transport. Probably Sanûris and Sanhûr, and the other villages on the edge of the second plateau, are the successors in time of the ancient elevated towns mentioned as ruined and abandoned.

Thus, instead of considering the remains of the old high-level abandoned towns as evidence destructive of the theory that the whole Fayûm was filled with water, I consider their testimony distinctly favours such a theory.

Those towns especially, whose ruins are found on the north side of Lake Qurûn, would certainly have been built near the then borders of the lake, as they could have had no possible source of water supply other than the lake itself. It, therefore, is a matter of great interest to determine the levels of any ancient towns that may be found on the north of the lake; and the more ancient the town and the more remote from the present lake, the more suggestive will be the facts that may be ascertained with reference to its levels.

Now there are two monuments of antiquity known in such a situation, namely, the ruins of Dimay (Dimeh or Dimé) and an ancient temple (if it is a temple) discovered by Dr. Schweinfurth 7 or 8 kilometres north of Dimay.[6] Dimay itself is 3 kilometres from the nearest point of the present Lake Qurûn, and the surface of its causeway or quay at its upper end, near the old town, is 69 metres above the water surface of the lake (May 2nd, 1892), or at R.L. + 25·44. The south end of the quay is now about 2·85 metres lower, but it was doubtless originally somewhat higher than this, as its present is not apparently its original surface, some of the layers of stone having disappeared.

I had a trench dug against this quay or causeway, at about the middle of its length, to determine the depth to which the masonry was carried down.

If this had been merely a causeway, it is not easy to understand the necessity for so great a depth of masonry. It was therefore more probably a quay projecting into the water. This quay is 400 metres long, and its direction is due north and south. The level of the plateau sloping up to the end of the causeway on the south of Dimay is from R.L. 13·00 to 17·00; the plateau on the north side of the ruins is at R.L. 21·45.

The ruins of Dimay are Roman on the surface, but I do not know if it has been established that below the Roman remains there do not exist more ancient ones. Dr. Schweinfurth thus expresses his opinion about this old town: “Dimé seems to have filled the position of ‘tête-de-pont’ in relation to the Fayûm, as in consequence of its strong position, it afforded a secure outlet and final station for the caravan road opening out towards the Oasis. That the tribes of the Libyan Desert must even in the times of the Romans have been very restless and enterprising, is testified by the numerous similar fortifications, which in the day of the so-called good emperor, were erected on all the principal exits and entrances to the Oasis roads.”

Seven or eight kilometres north of Dimay (magnetic bearing from north entrance in Dimay enclosure wall 12° east of north) is found the ancient so-called temple, discovered by Dr. Schweinfurth in 1884. I give here photographs of the exterior and interior of the building, as well as its ground plan, that those who are capable of judging may have the means of estimating from them its probable age. ([Plates XIV.,] [XV.,] and [XVI.]) The important level, so far as the subject of this paper is concerned, of the old town, marked by mounds of ancient pottery on the south of the “temple,” was determined on the occasion of my visit. The level of the upper parts of these mounds was found to be R.L. + 24·58. The pottery was, of course, spread out to lower levels, but probably the ancient town was built between the levels of 23·00 and 26·00.

Dr. Schweinfurth remarks that the buildings dating from the XIIIth Dynasty are all distinguished by the same kind of four-cornered arrangement as this temple and generally scorn every kind of ornament; and he notes that the great size of the blocks and peculiar method of fitting the stones together give it a resemblance in style to other old buildings. Instead of giving his further description, I refer to the ground plan and photographs. It is worth noticing that the north-west room has no visible means of communication either with the exterior or with the other chambers of the building; also that the displacement of the stones, forming the upper half of the chambers on the raised floor, is suggestive of an earthquake, the upper stones having slid on the lower to a measurable extent in a north-easterly direction. Cracks in the roofing stones corresponding with the displacement seem to confirm the theory of earthquake action.

Plate XV.

INTERIOR OF DR. SCHWEINFURTH’S “TEMPLE,”

FROM WEST END OF OPEN ROOM.

Plate XVI.

PLAN OF OLD BUILDING DISCOVERED BY DR. G. SCHWEINFURTH IN 1884.

Height of chambers from surface of raised floor to ceiling 2·65. Scale ¹⁄₁₀₀. Dimensions in metres.

The object of the building is a riddle. Each of the raised cells has a recess for a door. “In the thickness of the south wall, on the east side of the principal entrance, runs a passage half a metre wide, leading to which, at the south-east corner of the temple, a door of equally narrow proportions is attached. This passage leads downwards to the chambers below” (Schweinfurth). Dr. Schweinfurth came to the conclusion “that the old temple, as well as the original settlement or formation, is one of the monuments belonging to the oldest times.”

Concerning the old town he writes:—“In the neighbourhood of the temple, from south-east to south-west, at a distance of about 500 paces, that is, on the edge of the rising ground, there are quantities of potsherds lying in heaps here and there. They are of the most weather-worn appearance, and have formed portions of coarse, thick vessels. No such things as fragments approaching the pottery work of the Greek or Roman period are found. The eye of the seeker sought in vain for remnants of that blue glazed pottery ordinarily so common, or the long amphoræ of the Greek shape.

“The amphoræ points or ends, which I picked up, were all stumps, and of an almost cylindrical shape. The corresponding pottery showed no sign of rings. They were almost entirely coarse, red clay fragments, with here and there a yellow or black bit, and all distinctly showed the work of the potter’s wheel.

“Below the scarp of the lowest rising ground no more pottery was to be found, neither did the marl mounds display on examination any admixture of manufactured pieces. The heaps of pottery formerly existing appear to have been flattened down and spread out over a much wider space by the disintegration and sweeping down of the marl bed. A similar occurrence may be observed on the few stone walls yet remaining of the old temple settlement.”

For Schweinfurth’s further remarks see pp. 101 to 107 of his veloci-graphed letter to Paul Ascherson on his journey in the depression of the Fayûm, 1886.

The line of levels, which I had taken between this old building (temple) and Dimay, followed a direct line between the two, crossing the elevations and depressions given in the list below:—

From Schweinfurth’s “Temple” toDimay.
R.L.
Floor surface of raised chamber on left of central chamber35·506
Pottery mound of old settlement24·580
First depression on line of levels9·611
Following elevation16·521
Second depression6·096
Following elevation14·461
Third depression7·716
Plateau north of Dimay21·448
On ruined mounds in Dimay enclosure28·368
Causeway at undamaged upper end25·438
From Dimay to LakeQurûn.
Causeway25·438
Plateau north of Dimay, upper end17·000
„ „ lowerend13·270
Fossils plentiful between- 3·500
and- 13·000
Water surface, Lake Qurûn, May 2nd, 1892- 43·540

These levels I am convinced are correct, as they were taken with the utmost care, as I myself saw, by Messrs. W. O. Joseph and A. Pini, who had been in constant practice at levelling. The levels between Lake Qurûn and Dimay were taken twice over; the first levels, taken by Monsieur Pini alone, giving a difference of level between the lake and causeway of 68·952 metres, while the difference found, when both read, was 68·978.

The levels for the old town near Schweinfurth’s “temple” having been found to be from R.L. 23 to 26, the theory that Lake Mœris was a little below the level of R.L. 23·00 is favoured by the determination of this level. The presence and peculiarities of the quay at Dimay, if it is such, and the existence of an old town on the heights where the Dimay ruins stand, if they can be used as evidence of what the lake level used to be, point to high levels rather than to low ones, and do not answer to Linant’s appeal to the old abandoned towns to bear witness in his favour.

In connection with the levels of Dimay and Schweinfurth’s “temple” the levels of the ruins of Biahmu should be studied. These are given on [Plates XXII.] and [XXIII.]

The top of the highest corner-stone of the enclosure wall, now in situ, is at R.L. 21·59, and, accepting Mr. Petrie’s restoration of these ruins, the top of this wall, when complete, would have been at R.L. 23·00, which would seem to indicate that the maximum water-level of the lake was below R.L. 23·00, but higher than R.L. 17·00, the level of the ground outside the enclosure. These ruins are referred to more fully on [p. 83] et seq.

Mr. Flinders Petrie’s Views of Lake Mœris.—Having discussed the theories of Linant Pasha and Mr. Cope Whitehouse, the only two that I can find stated with any distinctness, and the only ones that have been put forward by travellers having a personal acquaintance with the Fayûm, I will, before setting forth my own reading of the past history of the province and my theory as to its connection or identity with Lake Mœris, first give Mr. Petrie’s views, who should be included with the two foregoing theorists, as a traveller having a personal acquaintance with the Fayûm, and, in a special line, a very intimate one. I do not think that he would claim that the expression of his views constitutes the enunciation of a new theory of Lake Mœris, but only his way of viewing an old theory with some side-lights of his own added by way of illumination.

The views, that I have adopted, are in general agreement with those favoured by Mr. Petrie, and as he, an Egyptologist and archæologist, has thrown light on the subject from his standpoint, I propose to make the same attempt from my point of view as the Public Works officer in charge of the irrigation of the Fayûm. The working out of the problem of Lake Mœris would seem to require an alliance between a palæontologist, an archæologist, an Egyptologist, a geologist, and a hydraulic engineer.

The following is copied from ‘Hawara, Biahmu, and Arsinoë,’ by W. M. Flinders Petrie, published in 1889:—

“Medinet el Fayûm ([Plate XVII.]) is the modern town which represents the ancient Arsinoë, so named by Ptolemy Philadelphos in honour of his sister-wife; it lies at the extreme south of the old site, which covers a space of over a mile long and half a mile wide, a vast wilderness of mounds strewn with pottery. At the opposite end of the ruins, toward the north, is the great temple enclosure of the old Egyptian town. Before its name of Arsinoë, the city had obtained the name of Crocodilopolis, from the worship of the sacred crocodiles maintained there; and still earlier it was known as Shed, meaning, apparently, that which is saved, cut out, delivered, or extracted, referring to the district being reclaimed from the great lake. The whole province was known as Ta-she, ‘the land of the lake’; and, whatever may have been the mistakes of historians about Lake Moiris, there is no doubt that the lake was the main feature of the district.

Plate XVII.

VIEW OF MEDINET EL FAYÛM,

WHICH OCCUPIES PART OF THE SITE OF THE ANCIENT TOWN CALLED SUCCESSIVELY “SHED,” “CROCODILOPOLIS,” AND “ARSINOË.”

“So many opinions have been broached about Lake Moiris that an account of antiquities in the Fayûm without mentioning it would seem impossible. So, although my work has not been in that line, yet it will be well to state what seems to be the truth about it, in order that some collateral questions should be the better understood. For the following view of the use of the great dyke I am indebted to Colonel Ross, R.E., C.M.G., who has professionally considered the subject. The Fayûm is one of the oases of the Libyan Desert, lying close to the Nile Valley; and the intervening ground is low enough for the Nile to pour into the basin. The fall from the Nile Valley to where the channel widens out into the Fayûm is about 12 feet; and the water flows over the province by canals and ravines, worn through the rock and its superincumbent mud, until the streams finally collect in the Birket Kurûn at more than 200 feet below the Nile level, and, indeed, 130 feet below the sea. The present area of cultivation is about 20 miles in each direction; but the whole basin, geographically speaking, is about 40 miles across on an average. This does not include the secondary basin of the Wadi Raian to the south, which never had any connection with the Fayûm basin in historic times, the ground rising over 100 feet above Nile level between the two depressions.

“In pre-historic times the Nile Valley was full of water to a far greater depth than at present, probably 100 to 200 feet deep of water filled it right across. A river of such a size seems almost incredible, and we naturally should suppose it to have been an estuary; but this must not be too hastily assumed, as there are evidences over the whole country of an enormous rainfall, which ploughed up the cliffs with great ravines; while the bare bed of the old Nile in the eastern desert at Silsileh is some miles in width, showing what a large volume of water has filled it; a lesser stream would have cut down a deep channel in the old bed, and would never have filled that and topped the rocks to force its present cut. This pre-historic high Nile is not, however, pre-human, as I found a palæolithic flint high up on the hills to the west of Esneh, clearly river-worn. The geologic conditions, then, in the pre-historic time prove that the Fayûm Basin must have been a vast lake, connected by a broad arm with the Nile Valley. Thick beds of Nile mud exist beneath 10 to 20 feet of deposits washed down from the desert hills; and even this desert detritus is strewn with felspar and quartz pebbles brought in by the Nile from Assuan, and now lying high above the present Nile level. As the rainfall ceased, and the Nile fell, the neck of water was reduced, but it still sufficed as a channel for the filling of the Fayûm, in all probability, in the time of the earliest dynasties. The Nile bed has risen, it is true, 4 inches a century by its deposits; and hence at the time of the XIIth dynasty, when it was down to its present volume of water, it probably stood about 14 feet lower than it does now in the Nile Valley; but as the drop to the point of flow into the Fayûm is at present 12 feet below high Nile, and the water-level has risen somewhat there, it is pretty well certain that the Fayûm Basin continued during the early dynasties to receive the inflow of the Nile as it had done for ages before. This, then, was the state in which the great engineering monarchs of Egypt found the province; a basin full of overflow Nile water, replenished at each inundation through a marshy shallow inlet, and with much of its bottom so raised by deposits as to have become almost marsh ground, like the present lakes about the coast.

“Amenemhat I. is the earliest king of whom we have any evidence in the Fayûm. He appears to have reclaimed the site of the capital, Shed, ‘the separated’ or ‘extracted,’ and thus he established ‘the land of the lake.’ The dyke of Amenemhat I. may perhaps be seen in a fragment of an enormous bank which remains on the north of the temple area at Medinet. It cannot be part of the temenos wall, as it is far too thick in proportion; and no king later than Amenemhat I. would need to place a dam so near to the capital. The great dyke noticed by Linant—if indeed it be ancient, which some have doubted—is probably the further reclamation of Amenemhat III., signalised by his erecting at Biahmu two great statues of himself at the projecting corner of it looking over the lake, and flanking the road on either side. That the water was on the lower and not the upper side of the dyke, as Linant supposed, is proved by the levels. For if the area within the dyke had been covered with water as a reservoir, the Biahmu structures would have been submerged some 12 feet; whereas there is no trace of deposited mud on any of the upper stones, nor is the building such that it is likely to have been placed in a depth of water. (See [Plates 22] and [23.]) The work of Amenemhat III. consisted in reclaiming more land, and damming back the lake to narrower limits, while improving the canals which led in and out of it, so as to render it more effective in co-operating with the Nile. He thus established Lake Mœris, and his works gave him the credit of being its founder in later ages. In the time of Herodotos the lake still seems to have been kept up to its high level, and if this view be correct, we ought not to find any pre-Greek remains in the Fayûm below Nile level outside of the great dyke; so far as is at present known this is the case. The circumference mentioned by Herodotos as equal to the coast of Egypt, would have been about 130 miles, against 180 length of the coast-line; so this statement is but little exaggerated. The length in stadia is, however, evidently wrong. Apparently under the Persians or Ptolemies the desire to acquire more land in the Fayûm at the expense of the irrigation of the Nile Valley, led to restricting the inflow, and gradually drying up the lake. It was reduced greatly during the Greek period, as the temple of Kasr Kerûn, of Roman age, on the shore of the Birket Kurûn, is 72 feet below Nile level; and Dimeh, a Roman town, is at 69 feet, and has a quay, I am informed, at about 87 feet below the Nile.[7] The shrinkage of the lake, however, went on until it has now left the Roman quay 130 feet high in the air, and the Nile falls over 200 feet before its waters evaporate from the lake. The present problem is how just to let in enough for cultivation without any surplus, and so still further reduce the lake, and increase the area for crops.

“The general level of cultivated land in the Fayûm has not risen by deposits as in the Nile Valley; the denudation by the rapid drainage into the lake just compensating the rise by deposit which would otherwise take place. The evidence for this is seen on the east side of Arsinoë, where the Bahr Tirseh has cut a clean section of the mounds, and the undisturbed bed of Nile mud beneath the ruins is seen to be at just the same level as the fields at present. Also at Biahmu it is certain that the ground has never been much below its present level, or the foundations would have been washed out; nor has it risen much above the level apparently, as the highest mud on the stones is only three feet over the present soil. The fact seems to be that it slowly rose while the lake was at a high level, until it was about two feet higher; and then it has denuded since the lake was reduced, and drainage set in, until it is now perhaps a foot below the ancient level of the XIIth dynasty.”

I have quoted Mr. Petrie in full, as he is reputed to be accurate in his statement of facts, and undoubtedly is so as regards his own discoveries and excavations.

I must now pass on to my own views, and set them forth in more detail.

CHAPTER IV.

HISTORY OF THE FAYÛM PROVINCE — THE FAYÛM BEFORE LAKE MŒRIS.

The past history of the Fayûm Province was probably the following.

In the beginning, the sea covered the whole of the area which afterwards became the Nile Valley and its bordering hills. By a slow process of upheaval the dry land appeared above the level of the waters, but, in the process, what was formerly the uniform bed of the sea became an uneven surface with heights and depressions and faults.

The Nile Valley, the Fayûm and Wadi Raiân depressions were the ultimate result of this action, the formation of the Nile Valley being completed by the flow of water. At first the upper reaches of the Nile Valley held its waters at a high level by barriers of rock, but in process of time these barriers were cut through, the bed scoured out by the constant flow of water, and the water surface lowered beyond its present levels, to be again gradually raised to the levels of to-day. The lower reaches of the Nile Valley were probably at first occupied by the sea, until the yearly deposit of the floods formed the Delta, and pushed the land thus formed further and further out, forcing the sea to retire. As the surface of the Delta became raised and prolonged by successive annual deposits, the bed and water-surface of the Nile also would have risen with it, until the levels at which the Nile flowed in its lower reaches became those of the present day.

At a point in the hills dividing the Nile Valley and the Fayûm, about 10 kilometres south of Lahûn, near Sidment-el-Gebel, Dr. Schweinfurth found “the indubitable witnesses of a Pliocene sea” preserved in the form of oysters (Ostrea cucullata and Pecten) in the white sand at about R.L. 60 to 70. (See [map] and [Plate XXI.]) The Pliocene sea, he maintains, intruded up the Nile Valley and extended on both sides of it as far as the contours of 60 to 70 metres above sea-level allowed. The place, where the oysters in the white sand were found, is situated in a flat depression on the plateau of the narrowest part of the hills separating the Nile Valley and the Fayûm. The Pliocene sea flowed here from one depression into the other, and would have succeeded in scouring away the barrier between the two depressions, if it had not been interrupted by a later upheaval or a withdrawal of the sea. In a similar manner there seems to have been made from Lahûn to Hawârah, the present communication between the Nile Valley and the Fayûm by which the Bahr Yûsuf entered to form Lake Mœris, either as an old Nile-arm or as an artificial branch of the natural arm.

Besides this passage, the desert tract on the north of it offers, as breaks in the higher ridge, several depressions, which must have been accessible to the Pliocene sea. The present railway line to the Fayûm crosses the hills at one of these depressions.

On account of the regularity of the limestone strata in the Fayûm and Wadi Raiân, a violent upheaval cannot be supposed to have been the cause that produced these two depressions, and it is more likely that they are the results of erosion and scour.

In a passage I have already quoted from Mr. Petrie’s writings, he states that in prehistoric times the Nile was a vastly greater river than it is now, due to an enormous rainfall. Let us then assume the Pliocene sea-level at R.L. 60 to 70, according to Dr. Schweinfurth, and an enormous volume of water coming down from the Upper Nile Valley according to Mr. Petrie. The sea which then invaded the Nile Valley would have been in communication with the Red Sea, and may have had a tide of 5 metres range, which would have complicated the currents, and added to the scouring action. Below Wâstah, the channel of the Nile Valley, contained between the Libyan and Arabian Hills, is much contracted. Under these conditions the floods from the Upper Nile would escape sideways through the depressions in the Libyan Hills into the Fayûm and the Wadi Raiân; into the latter by way of the Wadi Muellah, and possibly by other connections with the Nile Valley of a low enough level.

A large volume of water would thus be forced westwards out of the Nile Valley, and would find its way towards the sea to the west of Alexandria. In its endeavours to dig out a channel for itself it would erode laterally, or scour down vertically according as the softer material was found in one direction or the other. The different points of delivery and volumes of the water contributing to the flow, and the nature of the rock met with in its path would determine the form the channel would take at the various stages of its development. Tremendous eddies would be produced by projections of hard rock and contractions of the irregular channels, which would lift material from the bed and produce deep holes.

Had this action not been arrested by the further upheaval of the land, perhaps a second Nile Valley would have been formed branching from the main valley at Behnesa, passing through the Wadi Raiân and Fayûm depression, and continuing through the Wadis Fadhi and Faragh, west of Memphis and Cairo, to the Natron Lakes, and thence to the sea west of Alexandria; or returning to the Nile Valley, or side of what is now the Delta, but was then sea, at some point south of Alexandria.

If this theory is a sound one, the remarkable depressions of the Fayûm and Wadi Raiân are paralleled on a small scale by the deep holes (bayarât) scoured out below the bridges or cuts in the Upper Egypt Basin embankments, or outside a breach in a Nile bank.

The section, given on [Plate XVIII.,] of 50 miles of the Nile Valley and desert opposite Cairo, is taken from Mr. Cope Whitehouse’s article, entitled “The Pyramid Hill of Gizeh,” which appeared in the ‘Quarterly’ some time ago. It shows (assuming it on Mr. Whitehouse’s authority to be a correct representation of the ground) the channels, that I have named, in the arrested state of development which they had reached, when the flow of water, which was digging them out, was cut off.

Plate XVIII.

SECTION OF 50 MILES ON LAT. 30°.

Borrowed from Cope Whitehouse.

Note.—The dotted line represents the level of the Pliocene Sea, but is not in Cope Whitehouse’s section, which was drawn for another purpose.

After the upheaval had raised their borders above sea-level, the sea would be henceforward excluded from the depressions and be replaced by the waters of the Nile, which would have entered by the gap in the Libyan Hills at Lahûn. The upheaval continuing and the Nile at the same time scouring out its bed, a condition of levels would have come about, under which there would have been an annual inflow during the floods and outflow into the Nile on the floods subsiding.

In a long series of years there would result a thick deposit of Nile mud in the Fayûm, the richest deposit being found near the point where the waters first spread themselves out after passing through the comparatively narrow defile in the Libyan Hills. The tendency of the entrance of the waters, heavily charged with silt, into an extended basin filled with water would be to form a delta of Nile deposit similar to that which the Nile itself has formed in entering the sea, modified by the form of the basin bed, which would not have been uniform like that of the sea. On account of the momentum of the body of water leaving the defile and entering the lake, there would be formed a projecting ridge (contour R.L. 23) of deposit in the direction of the flow, while the deposit, resulting from the end and side spills, would form in gentle slopes with approximately parallel and rounded contours (R.L. 17 to 10) on both sides, and at the end of the projecting ridge as shown in [Plate XIX.]

Thus, in consequence of the former action of rain on the surrounding hills, greater or less at different points along the borders according as the inclination of the adjacent watersheds was towards or away from the depression, and in consequence also of the deposition of Nile mud by the annual entry of the river flood, the bed of the lake formed in the depression would take the shape shown by the contours on the diagram of the Fayûm, [Plate XIX.] The former of these processes of change of the bed and borders of the depression may have ceased before the latter commenced to operate, or both may have acted simultaneously or alternately, which would account for layers of Nile mud being found near the Hawârah pyramid lying below the water-borne detritus of the hills.

From a knowledge of the rules which govern the formation of a Delta, and the consequent raising of the level of the river which forms it, we might conclude that the Nile floods in past times were not as high as they are nowadays, though on the other hand we do not know that the floods were not greater in volume, and the probability is that they were. But whatever may be the truth about former Nile levels, the levels, at which Nile deposits are found in the Fayûm, furnish evidence of the maximum height to which the flood waters rose in the Lake.

At the commencement of the passage by which the waters entered the Fayûm, the highest Nile deposit is at R.L. 26·00. At Hawârah it is at R.L. 24·50, and along the ridge reaching out towards Medineh, R.L. 23·50. Probably, therefore, the water in the Lake reached about R.L. 26·50 at the commencement of the gorge, but the level of the Lake itself rarely, if ever, exceeded R.L. 25·00.

Plate XIX.

CONTOURED DIAGRAM OF THE FAYÛM DEPRESSION.

Note.—This being a diagram only, all minor folds and indentations of contours have been suppressed, so as to show more clearly the general shape.

The upper contours along the north-west side of the Lake must not be considered to be accurately represented, as no surveys of this side have been made.

It will be as well to determine, before going further, whether the present volumes of the Nile flood would suffice to fill the Lake Fayûm to the level of R.L. 25·00, which I have assumed it must have reached to account for the Nile deposits on its borders at R.L. 24·50.

At the time we are considering, no artificial works existed for controlling the inflow and outflow of the Lake.

We have first to determine the lowest level to which the Lake would have been lowered by the outflow and evaporation at the end of the summer, and before the next rise of the river commenced. The Nile may have flowed at a lower level then (that is, in very early prehistoric times) than now, the summer volume was probably greater then than now, as the unbreached barriers in the upper reaches would have ponded up the water into reservoirs, which, slowly emptying themselves, would have helped to raise the summer level; the flow-out also from the Fayûm Lake would have raised at its exit the level of the summer Nile, at least during the winter months, but not necessarily during the summer months, as it may have expended itself sooner. There are thus three unknown elements in the problem, and nothing to witness to the former minimum levels in the same way that the Nile deposit does to the maximum levels. We are therefore forced to base the calculations on existing levels, and to suppose that the effect on the water surface of the former lower level of the Nile bed was counterbalanced by the increased volume of water flowing in the river bed. At any rate at some period sooner or later the present minimum level of the Nile must have been reached.

The probability is that the exit channel of the lake joined the Nile at or near Wâstah. Up to the end of April the rate of fall of the river exceeds the rate at which evaporation would lower a lake surface, but in May the river falls about 15 centimetres, and not at all on an average in June. Hence, up to the end of April the fall of the river would determine the rate of fall of the lake, but in May and June the fall due to evaporation would rule the rate.

R.L.
The level of the Nile at Wâstahat the end of April may be taken to be18·75
The distance from Wâstah to Lahûn is30kilometres.
„ Lahûn to Hawârah15„
Total45„
Allowing a water surface slopefor the outflow of ¹⁄₂₅₀₀₀, the difference in water surface levelbetween the lake at Hawârah and the Nile at Wâstah would be1·80
Hence the water surfaceof the lake at the end of April would be at20·55
Evaporation would still furtherlower the surface in May by·25
„ „ „ June „·30
0·55
The water surface in the lakewould thus become20·00
Probably the commencement of theflow into the lake would not take place till a few days after themiddle of July, which may be taken as the time when the lakereaches its lowest level for the year. Evaporation for this periodof July must therefore also be allowed for, say0·20
The lowest level of thelake would therefore be19·80

The mean surface area of the Lake Fayûm between R.L. 19·80 and 25·00 may be taken as 2000 million square metres.

Evaporation during the ninety days of flood would tend to lower the level 70 centimetres.

The quantity of water required to raise the lake from R.L. 19·80 to 25·00 would therefore be 2,000,000,000 × (5·20 + 0·70) = 11,800 million cubic metres, or a daily average for ninety days of 131,111,111 cubic metres.

At the commencement of these ninety days the inflow would be small, increasing rapidly to the maximum; and again, as the lake level rose and the Nile began to fall in October, the inflow would gradually decrease to nothing by the end of the ninety days. Hence it would probably be necessary to suppose a maximum daily discharge into the lake of about 200 million cubic metres a day for part of the time.

12345
Date.Number of Years out of 16 in which the Supply given in Col. 3would be available for abstraction.Balance available after allowing for LowerEgypt.Corresponding Gauge, Beni Suef.Corresponding Gauge, Magnûnah Mouth on Nile.
million cubic metres per day.metres.metres.
Sept.11167⎫
⎬
⎭		Average
112		28·0826·64
„111110828·1126·67
„211116228·1426·70
Oct.113157⎫
⎬
⎭		Average
192		28·1426·70
„111217428·1526·71
„211424528·1226·68
Nov.11537228·0526·61
„111137227·0525·61
„21116726·4024·98
Dec.1126325·8824·40

Colonel Western, in a note on the Wadi Raiân, shows that for a certain number of years out of sixteen years (1872 to 1887, of which he had the statistics to work with) there is a surplus discharge in the Nile which might be abstracted without in any way interfering with the ordinary irrigation of the Delta. In his calculations he takes 565 million cubic metres in twenty-four hours as the discharge required by the Delta during September and the first half of October. He is, of course, referring to the conditions of the Delta at the present time. He gives the table which appears on the preceding page, to which I have added the corresponding gauge levels at Beni Suef and Magnûnah mouth for reference further on.

The month of August has not been given, as the conclusion was come to that there was no water to spare in August under present conditions.

The calculation, giving these figures, is made assuming that regulation on the Barrage below Cairo is not called in to assist; the discharges allowed to Lower Egypt, after abstracting the above quantities, being sufficient to give a water surface at the level required for irrigation without any heading-up. Now, the quantity required to fill the lake to R.L. 25·00, as found before, is 11,800 million cubic metres. This, let us suppose, would be made up thus:—

September30days at112millions=3,360millions.
October31„192„=5,952„
Parts of August and November29„86„=2,494„
Total11,806„

These discharges could be abstracted without affecting Lower Egypt irrigation, as it exists now, for eleven years out of sixteen. This, however, is not a quite correct statement as applied to each of the eleven years, since the discharges given in the table are the averages of those years in which a surplus discharge is available. Among these would be some very high years, in which it would be possible to fill the lake to a higher level than 25·00, and years when this level would not be reached.

Besides the years, for which the averages of surplus discharges are taken, there would be five years out of sixteen when the supply would fall short in September, the month of highest level.

There is no necessity in this stage to seek for a connection between the lake and the Nile for filling the lake, as the water would find its way in large volumes across all the low parts of the valley into the drainage depression along the edge of the Libyan Desert, now known as the Bahr Yûsuf.

The levels at which the Nile deposits are found in the Fayûm, the discharges which might be drawn off from the Nile, and the area of the Fayûm Lake are thus all in agreement with the supposition that the level of the Fayûm lake was yearly raised from about R.L. 20·00 to 25·00, and that the level attained was never sufficiently high to cause an overflow into the Wadi Raiân.