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Pelusium, of which Colonel Stokes has given very instructive details. The currents are found to be mainly dependent on the wind, the prevailing direction of which is north-westerly, as shown on the chart prepared by Admiral Spratt. The only positive contribution to our previous knowledge of the subject contained in Sir Henry Rawlinson's speech are the statements that the line of strongest current is that bordering on the • Damietta mouth of the Nile and the projecting coast east of • Port Said, and that the coast-line between these localities was found to have advanced considerably seaward, “in some * places nearly to the extent of three-quarters of a mile,' since the date of the survey made by Captain Mansell, R.N., in 1856. It is very possible to understand how the growth of the Nile delta, when it has passed beyond the shelter of Aboukir Point, may have been reduced from a secular average

of more than 20 yards per annum to a fifth or a sixth of that rate of increase, if we find that the material brought to the mouth of the river is swept towards the Syrian shore with such energy as to cause a seaward growth of 52 yards per annum of the shore of the Pelusiac Bay.

The most valuable contribution, however, which has been made to our positive knowledge of the deposits of the Nile is a measurement of the volume of the river, and of the proportion of matter held in solution and in suspension by its water, which has been made by Mr. Fowler, C.E., in the capacity of engineer-in-chief to the Khedive. Mr. Fowler has favoured us with abstracts of measurements taken when the river stood at different heights, as measured on the nilometer. During a period of sixteen years daily observations have been thus recorded; and the mean annual volume has been calculated for a year when the Nile attains the mean height of 6.87 metres in flood. The lowest tide included in the observations was 5.87 metres (in 1868); the highest 8.48 metres (in 1874). Analyses of the solid material contained in the water were made for Mr. Fowler every month during the year 1874 by the late Dr. Letheby.

The annual discharge of the Nile, on these data, amounts to ninety thousand seven hundred and sixty-eight millions of tons of water. More than two-thirds of this large volume is brought down during the watery tetrameny of the ancient Egyptian year, containing the months Mesori, Thoth, Paophi, and Athyr (in the fixed, not the vague, year), and nearly corresponding to our own August, September, October and November. In October the flow amounts to 19 milliards of tons. In June it is rather less than 1 milliards of tons. The im



portance of a knowledge of this variation of volume is due to the fact that the quantity of solid matter brought down by the High Nile is far larger in proportion than is the case when the river is low. The quantity of matter in suspension, in a given quantity of water, is four times as great in August as it is in May. The total estimate of solid matter, both in solution and suspension, brought down in the year is 62 millions of tons, But Mr. Fowler remarks that, as the water analysed was taken from the surface of the river, the results of analysis are far below the real proportion of solid matter. Professional experience leads him to the inference that the bulk of wet material actually deposited must be fully five times that of the solids obtained by chemical analysis.

Experience at the Cairo waterworks has shown that the solids deposited in a few hours by High Nile water amount to an inch in depth for 10 feet of water, or to part of the bulk. It is long since Mr. Shaw gave exactly the same proportion, as the result of experiment. If only two-thirds of this proportion be taken for the flow of the four months of High Nile alone, the result will be equal to the above estimate of five times the deposit estimated from Dr. Letheby's analysis. Thus, from two independent modes of investigation, it results that the minimum quantity of solid matter annually brought down by the Nile amounts to at least 300 millions of tons. If we attribute to this matter the specific gravity assigned by Professor Rankine to mud (which is intermediate between that of dry and of damp sand), we have a quantity of 240 millions of cube yards of annual deposit.

The waters of the Nile may be distinguished by their colour, at the time of inundation, for more than 10 leagues after their entrance into the sea. The soundings taken by Admiral Spratt, , R.N., off the coast of Africa, from Aboukir Bay to El Arish, give depths of from 14 to 20 fathoms at about 20 miles from the shore. We may, therefore, consider the deposits from the Nile to form a submarine hill, or sloping surface, from low-water level to the depths above indicated. If we take a mean depth of 10 fathoms, or 60 feet, as a vertical dimension, we find that the annual deposit of the Nile will cover an area of very nearly four square miles to that depth. If we double the estimate of depth we, of course, shall halve the estimate of area. It thus may be reduced to a mere matter of figures to show that the greater part of the superficies of Egypt to the north of the ancient site of Memphis, must have been raised above the level of the Mediterranean by the deposits of the Nile since the historic date of the founding of that city. The

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statement of Herodotus to that effect is thus fully verified by the measurements of Mr. Fowler.

At the time of the founding of Memphis, according to the statement recorded by the great historian, except the Theban nomos, all Egypt was marsh, and none of those parts which

exist below Lake Maris were above water. The area of the delta itself, between the two existing streams forming the Damietta and Rosetta mouths, is stated at something under 2,000 square miles. But the area indicated by Herodotus amounts to at least four times that dimension, as fairly as it is possible to compute from the irregularities of the actual coast and internal lines. M. Lenthéric makes it amount to 2,300,000 hectares. We shall find good reason to conclude that in the time of Herodotus the outlines of the coast occupied a position intermediate between that maintained in the time of Menes and that which is represented on our last hydrographic survey.

The earliest Egyptian literature yet deciphered speaks of Memphis as a city. The hieroglyphic characteristic is a pyramid; and the name in the inscriptions is read by Dr. Birch as “the city of the Mennefer pyramid,' or pyramids. The word 'men' means a port; although when it is used in that sense, it is usually accompanied by a determinative not employed in writing the name of Memphis . The meaning of the name men

. nofre may be fairly illustrated by the more modern names of Havre de Grace, or Portobello, or Newhaven.

Indeed, the foundation of a city at or near to the northern limit of the terra firma of Egypt suggests the establishment of a port, especially as the king to whom the choice of the site is attributed had his capital at Abydos. The hills now rising above the sand in the parallel of Memphis and of Suez, and the position of the pyramids, agree with the hypothesis that, at the early date in question, the statement made to Herodotus was accurately true, and that only marsh and occasional islets then presented any barrier between the Mediterranean and the Arabian Gulf.

Thus Herodotus is fully borne out in his assertion that the Egypt to which the Greeks of his time were in the habit of navigating was altogether made ground, and the gift of the river. If we understand him aright, he seems to intimate that a distance of seven days' sail from the sea to the vicinity of Lake Mæris, added to three days' sail further up the Nile, marked the extension of the Nile-formed land in his own time. There has been some difficulty in deciding on the actual distances which it was intended to define. He reckons in schäni, and says that each schænus was equal to 60 stadia. If these are to be regarded as Greek stadia, Herodotus would have over-stated both the length and breadth of Egypt by about 50 per cent. But the words of the passage in question are, “And each schænus, being Egyptian measure, 60 stadia.' If we understand that an Egyptian stadium is intended, we have to ascertain the length of that measure by the actual distance between the indicated points. As closely as these can be ascertained, the distances quoted are accurately proportioned to one another. The distance in longitude from the Plinthinetian Bay to the Serbonian Bog is exactly proportionate to the distances in latitude from Elephantina to Thebes, and from Thebes to Heliopolis. As a fourth measurement of Herodotus is that from Heliopolis to the Sebennytic mouth of the Nile, we have here a measurement of the seaward extension of the delta in the last 2,300 years.

The schænus, if we take the above distances as determinative, is a length of 3} geographical miles, which is a unit very readily understood by those who are aware of the combination of divisions by 4, by 6, and by 10, which were used by the most ancient astronomers and geographers. Ptolemy, in the account of some of the ancient eclipses, which he gives in the Almagest, uses the Chaldean division of the day into 6 degrees, each consisting of 80 scrupules. The number 96, or its double, 192, is one that constantly recurs in the Chaldean scale, and has the advantage of being divisible by 2, 3, 4, and 6. The schænus, according to this determination, contains 192 seconds of latitude; and the studium is, consequently, equal to 98.77 metres. Jomard, in his Système Métrique des

Egyptiens,' makes the stadium used by Aristotle, Herodotus, and Megasthenes 99.75 metres in length. The difference is not of sufficient magnitude to interfere with the present inquiry, but the lower determination is more accordant than the higher with the Chaldean system of measures.

The distance given by Herodotus from Elephantina to Thebes is 30 schäni, being equal, according to the above determination, to 96 geographical miles, which is in as exact accordance with facts as can be required. From Thebes to Heliopolis the distance of 81 schæni gives 259-2 geographical miles. The position indicated for Heliopolis in modern maps is about 6 miles further north than the site thus fixed. But it is probable that the point indicated by Herodotus is that of the apex of the delta, or first bifurcation of the Nile. The occurrences of islands and loops of the river renders it difficult to indicate the exact head of the delta even at the

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present time. A spot 400 kilometres to the north of the parallel of 30° is that which may be taken with the nearest approach to accuracy as the present position of the first division of the Nile into two main branches or channels; and this determination agrees so closely with that arrived at from the measurements given by Herodotus, that there can be but little doubt of the secular permanence of the true apex of the delta. The distance of 36 schæni, or 112•2 geographical miles, from the Plinthinetian Bay to the Serbonian Lake, is, again, as accurate as it is possible to determine. There remains a distance of 21 schæni, or 67.2 geographical miles, from Heliopolis to the Sebennytic mouth of the Nile. This would place the northward termination of the delta in the time of Herodotus in latitude 31° 8' N., or 33 geographical miles southward of the existing coast-line, as laid down in Admiral Spratt's Survey in 1858.

Against this very simple and consistent reading of the account given by the great historian, it has been attempted to adduce evidence from Strabo. The only pretext, however, for so doing is taken from an identification, which is altogether imaginary, of the ruins of the Bourg el Tineh, or the mounds of Faramah, with the ancient Pelusium. Admiral Spratt, in his • Investigation of the Effect of the Prevailing Wave • Influence on the Nile Deposits,' states that the name Faramah applies to the whole chain of mounds lying l} miles to the south-east of the Bourg el Tineh, and that they indicate the site of the city of Pharamia, of the times of the Crusades, a place which is mentioned in Michaud's Croisades' as a distinct city from Pelusium. Tineh, indeed, is an Arabic word, signifying mud; and the name Pelusium is derived from a Greek word of the same meaning. On this coincidence (being only that of names which might with equal propriety apply to any buildings in a district won from the mud of the Nile) the attempted identification entirely hangs. Bourg el Tineh, however, is on the right bank of the ancient Pelusiac branch, according to Admiral Spratt's Survey. Pelusium, according to the account given by Josephus of the march of Titus, was on the left bank of that stream. There is, moreover, a passage in Strabo which has not been hitherto cited, but which is in exact accordance with the position of the Sebennytic mouth fixed by Herodotus. This passage fixes the site of Pelusium at 26 schæni from the apex of the delta; a distance which, considering the eastern inclination of the Pelusiac branch of the Nile, very accurately coincides with the previously quoted

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