Papers Relating to the Foreign Relations of the United States, Transmitted to Congress, with the Annual Message of the President, December 6, 1875, Volume I
No. 35.
Mr. Heap to Mr. Hunter.
Tunis, November 14, 1874. (Received December 10.)
Sir: I have the honor to inclose a notice on the “inland sea of North Africa,” which has been so much discussed in France and elsewhere. When I wrote on this subject, in my dispatch No. 176,* dated June 2, [Page 65] 1874, I was impressed with the belief that the undertaking of opening a communication between the sea at Gabes, on the eastern coast of this regency and the Great Desert was quite practicable. Even M. Fuchs, whose recent report is adverse to it, was at that time quite convinced that there existed no great material obstacle to the introduction of the waters of the sea into the schotts, but when I saw him on his return from an exploration of this region last summer, his opinion was quite changed.
I have prepared two rough sketches or maps to accompany the report, which will, I hope, make it more intelligible.
I am, &c.,
the inland sea of north africa.
Much has been recently said and written in regard to the re-opening of a canal which, it is supposed, once connected the waters of the Mediterranean with those of a large lake or sea in the interior of Africa, at a point on the coast of Gabes, in the southern part of the Regency of Tunis.
This interesting subject, as much from the novelty and boldness of the conception as the advantages that might accrue to commerce by the opening of so extensive and almost unknown a region to its influences, has been received with interest by scientific bodies in France and elsewhere. They have even indulged in speculations on the effect this large body of water might produce on the climate of Algeria and Tunis, Sardinia and Sicily. The most ancient traditions have been revived to give a foundation to the belief that there once existed in this region a sea that was navigable; and, starting from the hypothesis that Jason and his Argonauts actually entered and navigated it, everything has been brought to bear to prove that there was anciently a large body of water in the interior of the Great Desert, which communicated with and was fed by the waters of the Mediterranean, and that it is feasible, by an outlay of a few millions, to re-establish this communication, and thus open to commerce a region as extensive as that washed by some of our larger lakes.
On the other hand, the skeptical do not believe that such a sea ever existed, unless at some remote period of the earth’s history, and that the physical obstacles that oppose its creation at the present time are, practically, too great to be overcome. The description of Herodotus of the voyage of Jason in search of the Golden Fleece, and the actual existence of half-submerged lands in the Great Desert, are the grounds for the belief that within historical times there existed in this part of Africa a considerable body of water, known to the ancients as the “Great Lake, or the Bay of Triton.” In support of this theory, there actually does exist, in a line extending from a point near the Gulf of Gabes, on the east, to the seven degrees and thirty minutes of eastern longitude from London, a series of schotts and sebkhas, the westernmost of which has been ascertained by actual measurement to be below the level of the sea. Schott, in Arabic, signifies the “bottom of a lake left dry, or nearly so, by evaporation during summer,” and sebkha “a saline marsh.” The most western of these schotts is Mel Rir, which connects to the east with Schott Sellem; they are both in Algeria. Between Schott Sellem and the Gulf of Gabes is a series of schotts and sebkhas, the largest of which, El Gramis, El Rharsa, or El Faraoon, and El Fejej, or El Djerid, are in the Regency of Tunis. Schott El Fejej is the nearest to the Mediterranean, the distance being variously estimated at from thirteen to nineteen miles. Captain Pricot de Sainte Marie, attached to the staff of the French army in Algeria, was instructed in 1845 to take levels from the Schott El Fejej to Gabes, (the ancient Tacape,) on the Tunisian coast. His report is deposited in the archives of the ministry of war at Paris. In 1873, Captain Roudaire, also an officer of the staff, was directed to ascertain the altitude of the town of Biskra, in the province of Constantina, Algeria, which was approximately fixed at three hundred and eighty feet above the level of the sea.
Pursuing his topographical observations, Captain Roudaire calculated that the western part of Schott Mel Rir was 87 feet below the level of the sea, and as the depression went on increasing toward the east, he deduced from this circumstance that the level of Schott Sellem must be 132 feet. He is of opinion that this depression continues through all the schotts to the eastern extremity of Schott El Fejej, and as the latter, according to him, is only thirteen miles from the Gulf of Gabes, he thinks that it would [Page 66] be easy, by removing the sand-banks and other deposits which have accumulated in the course of time, to reopen the ancient canal, through which, it is averred, the waters of the Mediterranean flowed into these depressions, and thus re-establish the inland sea mentioned by ancient geographers. Schott Mel Rir is about forty miles south of Biskra, in Algeria, and covers an area of one thousand three hundred and fifty square miles, and, according to the partial surveys of the schotts and surrounding country, the French officers compute that the inland sea would be about two hundred and twenty-five miles in length by about fifty in breadth, covering an area of about one thousand two hundred square miles. These are, in brief, the grounds upon which is based the belief that this inland sea existed in former ages, and that it could be re-established at a maximum expense of 20,000,000 francs.
A survey, however, was made in the summer of the present year .by Mr. Fuchs, an eminent French professor of geology and mineralogy who was charged by the Tunisian government to report on the mineral resources of the regency, and it goes to prove that the conformation of the country between Gabes and the Schott El Fejej presents physical obstacles of such a nature as to render it impossible that a communication could have ever existed between the Mediterranean and the schotts. Fuchs distinctly affirms in his report—
- 1.
- That the eastern extremity of the Schott El Fejej lies between two small ranges of mountains running from west-northwest to east-southeast, composed of sediments and deposits belonging to the Tertiary period, and that both ranges diminish in height as they approach the coast.
- 2.
- That these two ranges of mountains are united at their eastern end by a series of hills, which run parallel to the coast, and, consequently, between the sea and the Schott El Fejej.
- 3.
- That the highest of these hills or table-lands has an elevation of about 333 feet above the level of the sea, and that the minimum elevation is 165 feet, where they connect with the northern range of mountains.
- 4th.
- That this barrier is composed of alternate layers of ferruginous and quartzose sandstone superposed upon compact limestone, probably of the Eocene period.
- 5th.
- That the slope of these table-lands, as well as of the two ranges of mountains, is gradually and uniformly toward the sea. Oh the side of the Schott El Fejej it is more irregular and cut into terraces.
But the fact of the greatest importance to note is that the saline plain or sebka of El Fejej is, according to the barometrical observations of Professor Fuchs, probably 82 feet, and certainly not less than 66 feet above the level of the sea. It is crossed, moreover, by a narrow natural causeway (the road to Gafsa) at about 13 miles from its eastern extremity, and consequently, if there is a depression in this schott or sebka below the sea-level, it must be looked for at a considerable distance to the westward of this causeway. Mr. Fuchs comes to the conclusion that the formidable barrier which intervenes between the Gulf of Gabes and Schott El Fejej, as well as its geological structure, are convincing proofs that no connection could have existed within historical times between the Mediterranean and the desert at this point, an opinion which a more minute and accurate survey will probably prove to be the correct one.
Rennell, in his geographical system of Herodotus, cautiously states that if the lake or bay of Triton ever did exist, its communication with the sea could only have been by the valley or bed of the river Akarit, which, following Shaw, he conjectures to be the river Triton, it being the nearest point from the Gulf of Gabes to the Schott El Fejej, or Djerid. It is certain, however, that all the streams on this coast which take their rise in the mountains that inclose the Schott El Fejej, such as the Akarit, El Hammah, El Melah, and others, flow directly into the Mediterranean, and not into the schott, which they would do if the depression of the land were toward it.
Shaw, who visited these localities in the early part of the eighteenth Century, and who describes them minutely, says, “Yet we shall be at a loss to account for the river Triton, which, according to Ptolemy and other ancient geographers, is made to pass through the lake (Schott Djerid) in its course to the sea. I have already described this river and observed that it hath no such situation, though from its falling into the sea at Gabes, the ancient Tacape, this, without doubt, must be the Triton of the ancients. Besides, the water, both of the river Triton and the brook El Hammah, is very sweet and wholesome; but that of this lake (and indeed of most others that I have tasted in Africa) hath a saltness not inferior to that of the sea, a circumstance which alone may be a sufficient proof that there could be no open communication at least between them.”
This fact confirms Mr. Fuchs’s statement to the effect that the elevation of the barrier renders any communication between the Mediterranean and the regions of the Sahara physically impossible. It has been already stated that the shortest distance from the sea to the eastern extremity of Schott El Fejej, is 13 miles, and that there is a similar distance from this end of the schott to the natural causeway which crosses it. In the supposition, therefore, that the sea-level is found at only 20 miles west of the causeway toward the Schotts Faraoon, Sellem, and Mel Rir, it will be necessary for the [Page 67] canal to be at least 46 miles in-length, instead of 11, as M. de Lesseps calculates, through a cutting at the lowest summit of the barrier of 165 feet, to which must be added the depth of the canal, at least 20 feet. It is calculated that the canal must have a breadth of 100 yards throughout its length, in order to admit a sufficient body of water to supply the loss by evaporation. It would be superfluous to dwell on the immense outlay it would entail to remove the enormous mass of rock, sand, and earth which forms the present barrier between the schotts and the Gulf of Gabes. It would probably exceed that incurred for the canal of Suez, with results utterly incommensurate with such an expense, and to this expenditure must be added the cost of the oases, date-plantations, and cultivated lands that would necessarily be submerged in the district of Neftaona, in the Regency of Tunis, and the consequent destruction of the prosperity of the towns of Tozer, Nefta, &c.
It is impossible to say at what remote period Of the earth’s history the great desert of Sahara or any portion of the continent of Africa was covered by the sea, but it is evident, from the present conformation of the country between the Gulf of Gabes and the schotts or sebkhas, and the geological researches of Professor Fuchs, that if the Mediterranean ever communicated with the Sahara, it must have been in prehistoric times, since he traces the barrier which separates them to the Tertiary period. There is no question, however, as to the existence of sebkhas and saline deposits in the Regency of Tunis, as well as in Algeria and other parts of Africa, at different levels, and some undoubtedly beneath that of the sea. They receive water during the rainy sea-sons from the surrounding water-sheds, and lose it by evaporation during the intense heat of summer. It may be fairly deduced from this circumstance that the Sahara receives in like manner its water from the rivers that flow into it from the mountains of Auresor Djebel Khaddon, which, from their great height, are frequently capped with snow in winter, and may, in remote times, under different physical and atmospheric conditions, have supplied the Sahara with a sufficient body of water to turn it into a considerable lake. Its separation from the sea by the natural obstacles described above does not justify any other hypothesis.
At the time that Herodotus visited Libya, navigation was in its infancy, and it is scarcely presumable that two thousand four hundred years ago, there existed any geographical knowledge of this part of the world having a pretension to accuracy. It is not surprising, therefore, that he should have been led into error in describing places from hearsay and tradition, and not from personal observation.
We have, however, the description of the same localities, given at a much later date by Seylax, which, although incomplete and confused, affords explanations which tend to rectify in a measure the geographical errors committed by Herodotus in his narrative of the wanderings of the Argonauts in these almost unknown seas. He says: “The great bay of Triton is to be found inland; it shuts in the Lesser Syrtis, called Cercina, and the Lake of Triton with the Isle of Triton, as well as the mouth of the river of the same name. The entrance to the lake is narrow; an island is visible at low tide, when vessels are often prevented from passing through it.”
If we are to rely upon Herodotus, Seylax, and other ancient writers, as to the existence of a great lake or bay of Triton, we must look for it in other localities than the depressions of the Sahara and adjoining regions. It will be seen by the accompanying rough sketch or map that the Gulf of Gabes is shut in on the southeast by the island of Gerba, the ancient Brachion, and due north by the Kerkenah Islands, (Cercina.) The distance between these islands is forty miles, and the gulf is therefore completely open to the sea on the east. It must be borne in mind that the channel which separates the island of Gerba on the southeast from the main-land is very narrow and is fordable at low tide, but the native craft pass through it at high water in their voyages from the coast of Tripoli (Libya) to the Gulf of Gabes.
Between the island of Gerba and the continent is a body of water or fake, nearly circular, and about fifty miles in circumference. It is from one to eight fathoms in depth, with outlets to the sea on the northeast and northwest. In this lake there is a low island. The northwestern channel is somewhat masked by small islands and is deeper than the other. The navigators of antiquity, without charts or compass, rarely ventured out of sight of land. They steered along the coast in their small vessels, and it is more than probable that Jason in his course from east to west, closely following the coast of Libya, was driven by an easterly gale during high tide over the narrow entrance described by Seylax, into the lake or bay between the island of Gerba and the continent, from which he could find no outlet, owing to his ignorance of the existence of the northwestern channel, which, as already stated, is shut in from view by islands. He was prevented by the lowness of the water, after the storms had abated, from getting out through the channel by which he had entered the lake, and remained in his perilous position until extricated by a “Triton.”
This interpretation of the ancient geographers appears the rational one, on two grounds: First, had the Argonauts reached the Syrtis Minor, they would not have been inclosed by sands, as it is open to the eastward for a space of forty miles; and second, they could not have been driven into any other inland lake or bay, since all [Page 68] the streams on the coast, instead of running inland, take their rise in the hills and flow into the sea. Besides they are all unimportant brooks, and are nearly if not quite dry in summer.
The legend of the “Triton” is likewise susceptible of an explanation.
For upward of forty days in the early spring the tunny-fish, which frequently weigh upwards of four hundred pounds, pass along the coast of Africa in shoals of thousands. Their course is from west to east, and they hug the coast on their right, closely following the line of the shore. Coming to the northwestern entrance of the bay or lake of Gerba, they enter it, and, finding the northeastern channel too shallow to afford them a passage, they continue their course round the bay until they come again to the northwestern outlet, and issue from it, still keeping close to the shore of the island of Gerba, on their right, and continue their migration along the coast.
Jason, having entered by the northeast passage, found himself, as he imagined, in an inland sea from which there was no outlet, as the fall of the water prevented him from retracing his steps; but noticing large shoals of fish at a moderate depth—for the bay is nowhere over eight fathoms deep—he came to the conclusion that he would find an issue from the lake by following their course. In the wake of the tunny-fish are always to be seen numbers of porpoises—the dolphin of the ancients; and seeing that they all traveled in the same direction, the Argonauts could easily fancy that the protecting gods had sent these fish to lead them out of their difficulties. This explanation of Jason’s adventure, whose simple incidents have been exaggerated into the marvelous by tradition, seems more rational than to believe that there existed in this part of Africa a large body of water connected with the Mediterranean by a navigable channel, when recent and accurate explorations show that this was impossible, as a formidable and practically insurmountable barrier has existed there from a period so remote that the voyage of Jason and his companions in search of the Golden Fleece, involved as it is in the mists of antiquity, is as of yesterday in comparison.
Accompanying this report are two sketches or rough maps, a, showing the area or extent of the projected inland sea, and B, the eastern extremity of Schott El Fejej or El Djerid and the country between it and the sea, where the canal would have to be cut; also, the island and lake of Gerba, anciently Brachion, the supposed scene of Jason’s adventure.