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advance of the latter is admitted to be not more than nine or ten feet per annum. This double assertion is simply puerile. Its entire inaccuracy is not matter of opinion. The charts and soundings taken by Admiral Spratt, Captain Nares, Colonel Stokes, and other officers, are so careful and exact, that the information which they convey can only be ignored by a very wilful and determined ignorance. As to the actual rate at which either the Damietta or the Rosetta branch now annually protrudes its berge of sand into the Mediterranean, it can only be accurately determined by the comparison of successive surveys, such as those which have been made around the locality of Port Said. But Admiral Spratt states that a tower which was situated at the mouth of the Foum el Farez, one of the principal embouchures of Lake Menzaleh, at the time of the French occupation of Egypt, is now fully half-a-mile from the sea, owing to the encroachment of the shore. Between the years 1868 and 1873, according to the Report of Colonel Stokes,* the shore-line at Port Said has advanced 780 feet, being an encroachment on the sea at the rate of 52 yards per annum, or double our estimate of the secular
average encroachment of the Delta. In fact, the annual solid matter brought down by the Nile being an approximately constant quantity, a diminution of the advance of the delta at the embouchures of the river must be accompanied by an equivalent increase of the deposits in some part of the Mediterranean to the eastward of those embouchures.
The actual arrangement of the lagoons and strips or cordons of sand, which now form the greater portion of the seaboard along the entire coast-line of Egypt, is such as to indicate a considerable change in the littoral disposition of the deposits of the river since the formation of the last 30 or 40 miles of its channel; or, indeed, since the time when it was allowed to form its own course in continuation of the two artificial outlets mentioned by Herodotus, which have become portions of the two main existing branches known as the Rosetta and Damietta channels. The sands brought down by the first-named of these branches have been swept to the eastward by the littoral current, so as to form the cordon or belt of some 40 miles long, which separates the lagoon called Lake Bourlos from the sea. A similar cordon, of equal length, stretching eastward from the Damietta mouth, forms the northern shore of Lake Menzaleh. To the
* Egypt, No. 2. Correspondence respecting the Suez Cana'. Presented to both Houses of Parliament by command of Her Majesty, 1876. (See Chart at p. 30.)
east of the ruins of Bourg el Tineh, two parallel lagoons, extending for more than 50 miles from east to west, occupy the ancient position of the eastern part of the Pelusian bay. Over the entire district, the only part in which the delta has continued its original mode of solid growth, is within a range of some 40 miles to the westward of the Damietta branch, an area which has been entirely filled up by the action of the now choked up Sebennytic branch of the seven-mouthed Nile.
The annual change that is taking place on the shore of Egypt is only partially to be appreciated by a map or bird'seye view. It requires also to be measured by the sounding line, and delineated on a properly constructed section or contoured chart. In the immediate neighbourhood of Port Said this has been done. During the present year there has been presented to both Houses of Parliament, by command of Her Majesty, a comparative plan, showing the decrease of depth seaward from Port Said, from 1869 to 1873, which was drawn up by Colonel Stokes, and transmitted by that officer to the Earl of Derby on November 11, 1874. This plan shows the soundings taken from the French survey, of 1869, in black; those of Captain Nares, in 1870, in blue; and those of Captain Wharton, in 1873, in red. Colonel Stokes reports that between the dates of the two last-named surveys more than 5,000,000 cubic yards of solid matter have been thrown down between the present 18 and 30 feet lines of soundings to the west of a line drawn in continuation of the west pier of Port Said. In that time the 30-foot line has receded seawards 1,200 yards on the prolongation of the west pier, in other places for more than that distance. Over a space of 1,200 yards west to east, and 800 yards north to south, the depth has shoaled from 5 to 8 feet between the 30-foot line of 1870 and that of 1873.
This shoaling is probably local, being the direct effect of the check opposed to the littoral current by the pier of Port Said. But its magnitude is such as to intimate that the deposits of the Rosetta, as well as of the Damietta stream, are brought as far eastward as Port Said. If we suppose the volumes of the two branches to be approximately equal, and that the sand brought down by the Damietta mouth is gradually deposited by a littoral current of 3 miles wide over the 140 miles of coast to El Arish, we should not be able to anticipate a shoaling of more than from 3 to 4 inches per annum at a distance of 40 miles from the embouchure, which is the distance of Port Said. We find, however, from actual survey, a deposit of from 20 to 32 inches per annum within half-a-mile from the shore; an advance of the 30-foot line of soundings at the rate of 400 yards and more, and an encroachment of the coastline at the rate of 52 yards per annum. However narrowed be the area over which these changes are now actually in progress, they show the unabated activity of the mighty causes which have won the entire soil of Lower Egypt from the Mediterranean within the historic time that is covered by hieroglyphic inscriptions.
The secular changes in the face of Egypt comprise not only the advance of the shore-line into the Mediterranean, but a more or less imperceptible warping up of all the soil flooded by the Nile. The rise of the river itself, which was measured on a nilometer built into a wall at Elephantina, must be affected by the deposit on the face of the country below that spot. Herodotus states that in the reign of Moris a Nile flood of 8 cubits rise inundated all Egypt below Memphis. The only difficulty in this passage is as to date. Herodotus says the priests told him that the reign in question was 900 years before his own time. That number of years, however, only reaches back to the reign of Ramses Miamoun, of the nineteenth dynasty. The formation of Lake Mæris is dated 1,200 years before that reign ; and the name Mæris is that of a monarch of the twelfth dynasty, which reigned from B.C. 2812 to B.C. 2599. The general phenomena of the increase of the delta are far more consistent with the earlier than with the later of the two dates thus intimated; that is to say, with the period of the twelfth rather than that of the nineteenth dynasty, as having witnessed so low a rise of the Nile, especially when we consider that from the time of Herodotus to our own, but little variation has occurred in this respect. A minimum rise of 15 cubits was required, Herodotus says, to food the country in his day. The statue of Nilus in the Vatican is encircled by 16 amorini, symbolising the 16 cubits of rise which gave the omen of a fertile season in the time of the thirty-third dynasty. The nilometer at Elephantina gives a cubit of 21 inches, making the 16-cubit flood show a rise of 336 inches. During a period of sixteen years, according to the observations taken under the direction of Mr. Fowler, the average height of the flood was 6.87 metres, or 271.84 inches. The highest flood during this time was in 1874, when it rose 8.48 metres, or 335.25 inches, a very close reproduction of the 16 cubits of the time of the Ptolemies. The lowest was in 1868, being only 5.87 metres, or 232-27 inches, which is yet 64 inches higher than the rise referred to the time of Moris. It is certain that the less obstruction the flood met in its descent below Memphis, the less would be the height that it would maintain at that spot.
Mr. Horner endeavoured to form a scale of the antiquity of the delta by sinking a shaft beside the statue of Rameses, and measuring the depth of made earth that had accumulated since the erection of that statue. If his conclusions as to the original level, which are quoted by Sir Charles Lyell, are accurate, the rise of soil at the base of the statue has occurred only at the rate of 3 inches per century.
But Mr. Horner assumes that the ancient builders erected works of colossal magnitude on a site subject to annual inundation—a most improbable hypothesis. The true deduction to be drawn from the small accumulation above the platform of the statue is, that the low rise of the Nile referred by Herodotus to the time of Mæris had not been exceeded at the date when this sacred work was executed. Sir Charles Lyell estimates the rise at Elephantina at 5:3 inches, at Thebes at 4.9 inches, and at Heliopolis at 4.1 inches, per century. In none of these estimates does there appear to have been due attention given to the fact that the quantity of the matter held in suspension by the Nile during its floods varies in proportion to the depth of water. The nearer the surface, or the shallower the water, the less the deposit. Thus, comparing equal heights of food, less deposit would annually occur on higher than on lower ground, and less deposit on the same area year after year. Again, any obstructions that interfered with the flow of the food would have a powerful influence on the depth of deposit. It is thus conceivable, or indeed certain, that while inches were deposited in certain localities, feet would be deposited in others, in the same space of time. It is desirable to exhaust all the means of comparison in a question of this magnitude. But actual experiments as to the deposit made from a given depth of flood water, like those of Mr. Fowler, must yield far more luminous results than casual observations, which estimate the amount of secular change without due consideration of all the conditions that may have affected the exact locality.
A historical inquiry of considerable interest is connected with the physical history of the Egyptian delta. Considerable discussion has arisen as to the track indicated by the book of Exodus as that taken by the Israelites in their flight from Egypt. The choice of route lies within narrower limits than might be assigned from a hasty view of the map. Through the Gulf of Suez itself, from within a short distance of its northern extremity, the channel has a depth of at least 10 fathoms. The date of the Exodus, according to the most careful comparison of the various indications given in the VOL. CXLV. NO, CCXCVII.
Pentateuch and historic Hebrew books, was in the year 1541 B.C. ; which corresponds to the third year of the reign of King Thothmes IV., seventh king of the eighteenth dynasty. This monarch is spoken of in the inscriptions as the tamer of the • Syrian shepherds,' an expression which may very well be taken for the Egyptian account of an event which the Jewish historian regarded from so different a point of view. At this time, according to the estimate above given of the growth of the delta, the seaward apex of that formation must have been about 30° 54' of north latitude. The right bank, or shore, (taking the delta as maintaining approximately a series of parallel outlines during its growth,) would have been somewhere near the spot now occupied by Ismailia. The space now covered by Lakes Menzaleh, Ballah and Timpah, and the intervening and neighbouring marshy and sandy districts, must at that time either have been far below the level of the Mediterranean, or have been covered by lagoon and marsh, accessible to the waters of that sea, when driven by a westerly wind. On the right hand of the comparatively narrow isthmus then existing, the depression of the Bitter Lakes was, no doubt, connected with the Arabian Gulf. The main, or even the entire, distance which at that time divided the waters of the Arabian Gulf from those of the Mediterranean may, therefore, be taken to correspond to the Ym Suph, or sea of reeds, of the Pentateuch: a term which was first erroneously translated by Erythian or Red Sea, in the time of Ptolemy II., when the physical change which had gradually occurred in the isthmus had obscured the true meaning of the language of the Book of Exodus, accordant as it is with that used by Herodotus.
On this view of the case (the accuracy of which can only be a question of detail), several expressions which have perplexed the students of the Book of Exodus become perfectly clear and intelligible. When the flying bands, descending Wady Tomilat, which most Egyptologers identify with Goshen, arrived at the coast, the intention of their leader being to avoid the well-frequented track by the shore of Philistia, through the dominions of a people apt to arms, and experienced in resisting invasion from Egypt, the line of march was necessarily turned to the right. At night-fall, the people bivouacked on a grassy plain-the Coptic language yet preserves the word Pichairoth with this signification, which is also that of the term used in the Septuagint version-between the Pharos, or watch-tower on the shore (Migdol) and the Temple of Typhon (Baal Zephou), which may readily be identified with the ruin known as the Serapeum. The prevalence during the