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distance, stated by Herodotus, of 21 schoni from Heliopolis to the Sebennytic mouth.

If we take, then, the ancient bifurcation of the Nile, or apex of the delta, at 111 schoni from Elephantina, or in latitude 30° 0′ 12′′ N, which is in accordance with the latest map, we find that the extension of the delta from the date of the commencement of this bifurcation, or approximately from the era of Menes to the time of Herodotus, was 62 geographical miles. The period of time indicated, according to the Egyptian chronology, was 4,000 years. From the date of Herodotus to that of the Survey of Admiral Spratt, during a period of 2,300 years, the growth of the delta has been 33 geographical miles. Considering that the northward growth of the delta must become slower as the coast-line advances to the northwards, it would be impossible to find a more satisfactory check on the original calculation.

An independent verification of the measurements of Herodotus may be obtained by a careful examination of the map of Egypt. The large map prepared by M. Linant de Bellefonds leaves, indeed, very much to be desired in the way of clearness of definition, which may be to a great extent the fault of the lithographer. It also possesses the grave defect of confusing hypothetical with actual determinatives, especially with regard to positions thought to be mentioned in the Pentateuch. But it is the best survey of Egypt yet attainable; and the observations for which we refer to it are far within any conceivable limit of error.

It will be readily seen that engineering works of such importance as the formation of an artificial channel for the Nile, are likely to leave an impress on the face of the country. The whole course of the river, as is the case in most unrestrained channels, is tortuous and irregular. An artificial channel would be naturally straight. It is known that the present Rosetta branch of the Nile is the ancient Bolbitic channel, being one of those which is described by Herodotus as artificial. We find, on the map, a length of some 4,400 metres, extending from the Railway Bridge at Zaiad to a point in lat. 31° 0' 7", which gives every sign of having been originally artificial. It is approximately straight, and wider than the sinuous portions of the river, which exist to the north and recommence to the south of this part of the channel. Something of the same nature, though less distinct, may be traced in the parallel part of the Damietta branch, for a length of some 3,800 metres, terminating about 31° 0' 3". As Hero

dotus does not give the date of the excavation of either of these channels, it is not possible to state, on his authority, how far they must have terminated to the south of the latitude reached by the Sebennytic mouth in his day. It is certain that the latter was in the most advanced portion of the delta, and that the artificial mouths, when first opened, as being lateral, must have been to the south of the seaward head of the delta. A difference of 6 or 7 miles, therefore, such as actually exists between the latitude of the points indicated, brings us very close to what might have been expected. The difference at the present day between the lengths of the Rosetta and of the Damietta branches is given at 8 miles.

Continuing to use round numbers, as being really the most suitable for a calculation of this approximate nature, we find that the waters of the Nile have been the means of raising above the level of the Mediterranean, in a period of 6,300 years, an area of some 8,000 square miles. A square English mile, one yard thick, contains a little more than 3,000,000 cubic yards. We have seen that the annual deposit of the Nile amounts to 240,000,000 cubic yards. This would give an annual average increase of area of 1.27 miles, with a mean depth of deposit of 61 yards. In a boring made by Mr. Fowler at the east end of the Damietta barrage, the upper part of the ground consisted of brick earth, loam, and brown clay, to a depth of 114 metres, succeeded by 10 metres of running sand and silt, and then by alternate layers of coarse running sand, coarse sand and gravel, dark silt, fine yellow silt, coarse running sand, and fine running sand and silt, to the total depth of 37 metres. At this level no signs appeared of being near the bottom of the fluviatile deposit. At the distance of 13 miles from the present coast-line, Admiral Spratt found the bottom of the Mediterranean to contain no trace of the Nile deposits, but to consist of pure sea productions, viz. pure coral, coral sand, and shells. The depth was 31 fathoms, or 62 yards a very remarkable verification of the accuracy of the foregoing estimate. The actual encroachment of the shore at Port Said, between 1868 and 1873, has been at the rate of 52 yards per annum, notwithstanding the distance from the Damietta embouchure of the Nile, or more than double the mean annual encroachment of the delta since historic times.

It will be seen that we have been able to collect a series of data from widely differing sources, the results of which show an accordance that approaches very nearly to demonstration. The present outline of the Egyptian coast, together with the soundings, is taken from the Reports of Admiral Spratt, R.N.,

in 1858. The positions of the apex of the delta, and of the Sebennytic mouth of the Nile, in the time of Herodotus, are referred to actual latitudes by the distances given by that historian from Elephantina and from Thebes. The approximate position, four centuries later, of the Pelusiac mouth is given by Strabo. The quantity of solid material annually brought down by the Nile is ascertained by the admeasurements of Mr. Fowler. For the first time these various records have been compared, and they mutually vouch for each other's accuracy. It remains for us to inquire into the evidence that may be obtained as to the annual changes to which the coast of Egypt is subjected under the conditions actually existing at the present time.

The prevailing winds, and therefore the prevailing wave movement, off the coast of Egypt, are from the north, or north-west, according to the observations of Admiral Spratt. Off Alexandria the coast and shallows are rocky, and not sandy; the coast as far as Cyrene westward being formed of a rocky shore line, broken into headlands, which are the spurs or salient bases of mountain ranges. Abukir Castle stands on the extremity of this rocky shore, on a spur of land which formerly jutted out as a natural mole into the sea, rising from 50 to 100 feet above the water level. Westward of this natural groin the sea is deep, as well as unencumbered with sand; a depth of 100 feet being attained within two miles of the shore. As soon, then, as the secular growth of the delta brought the apex of that formation northward of the shelter of the Abukir reef, the deposits at the mouths of the Nile became exposed to the full swell and current of the Mediterranean, and instead of being allowed to settle in comparatively still water, were each year more and more dispersed along the coast to the eastward, as far as the shore of Syria itself. Nor are they absolutely arrested by that shore. The sand, when dry, is blown up from the margin of the sea. In some places it accumulates in dunes. All along the coast, as far as Jaffa, it is steadily advancing on the land, where it is not encountered by fir plantations; and is overwhelming the beautiful gardens near that town (which were celebrated for their fertility as far back as the date of the eighteenth Egyptian dynasty), at the rate of a yard per annum.

The members of that pleasant excursion party which M. de Lesseps dignified by the name of the International Commis'sion, and hurried up the Nile and across the Isthmus of Suez as the guests of the Khedive, report that all the sands brought down by the Nile are deposited at its mouth; and that the

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 Canal. 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

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