The exploration of Tibesti, Erdi, Borkou, and Ennedi in 1912-1917

What struck me most in this town is its well-kept and green appearance; the streets are wide, the houses in good repair and surrounded with trees (mostly serrahs). There are none of the hovels, the broken-down walls, the heaps of refuse so often found in Sudanese cities, except perhaps on the south side, where, at the time of my passing through the town, a group of Fellatas had set up a camp of dirty little straw huts in which men, women, children, and cattle sprawled in an indiscriminate heap.

The sultan Ali Dinar, who had spent part of his youth in the valley of the Nile with the Khalif of the Mahdists, had acquired there a taste for green trees, fine houses, and broad avenues. His palace had been carefully constructed. The principal building, a rectangular white house two stories high, surmounted by a terrace, opened northwards on to a garden planted with palms and lemon-trees. The rooms were large and comfortable, and from the second storey windows the Sultan could see not only the whole of his palace and his capital, but also a vast panorama over the surrounding plain, the valley of the Wadi El Ko, the mountains of Kebkebia, and even the Djebel Marra, whose imposing mass can be seen when the sky is very clear, more than 70 miles to the south-west. Other houses, less sumptuous, but more original because local in style, equally attract one’s notice in the interior of this palace, in which one loses one’s self in a labyrinth of walls, courtyards, and outbuildings. These houses are large round huts with simple clay walls, but whose roofs, admirably thatched, are often connected by long wide verandahs. These were the apartments of the princesses, light, roomy, and comfortable. Ali Dinar’s æsthetic preoccupations have been rare among Sudanese monarchs, but it must be admitted that in order to embellish his palace and his capital he had all but ruined his kingdom, reducing half the population to a sort of semi-slavery, filling his harem with concubines, distributing his subjects’ cattle among his favourites and the Arab merchants who brought him precious merchandise and weapons and ammunition sent by the Senoussists. He dreamed of extending his empire, and lent a too ready ear to the preachers of the Holy War, who, under the ægis of the Grand Senoussi and the Grand Turk, dreamed of driving French and British out of Africa. It was with him as with so many other despots: he fell through pride. Had he shown more wisdom and diplomacy he might well have been reigning still in Dar Four.

There would be many more things to say about El Fasher, but I have already dallied too long over the pleasant memories left me by my sojourn in that town. I beg to be excused inasmuch as, though I was still 1700 miles from Cairo, I considered myself as having reached the end of my journey. There only remained three weeks’ march with camels that would bring me to the railway terminus at El Obeid across an inhabited country not merely known but already organized; I must leave the pleasure of describing it to one or another of the British officers who have conquered and pacified it, and who know it better than I, who passed through it too quickly to be able to study it as it deserves.

From El Fasher to Cairo.—I left El Fasher in the evening of 21 July 1917, passing through Um Gedada and Dam Gamad to El Nahud, where I arrived on August 4. I left again on the 6th, deeply touched by the hearty welcome of the District Inspector, Major J. G. N. Bardwell. On August 13, towards four in the afternoon, as I came within sight of El Obeid, I heard for the first time in five years the whistle of a locomotive, and its strident note was sweeter to my ears than the most classical music, for it told me that I had at last reached the gate of civilization; and the same evening, at dinner with His Excellency the Governor of Kordofan, Mr. J. W. Sagar, the sight of the graceful and charmingly dressed ladies who were present confirmed that delightful impression.

The next day was a very busy one, for I had to discharge my native escort, pay my camel-drivers, put in order, mend, and bring to the train my numerous cases of instruments, collections, and documents, in order to take on the Wednesday the bi-weekly train. I was only able to do so thanks to the unwearied kindness of the Governor and of the Garrison Commander, Major T. S. Vandeleur, D.S.O.

On August 15, at 7 o’clock in the morning, I took the train for Khartoum. The faithful blacks who had come with me all the way from Borkou were filled with gaping wonder at the sight of the long heavy string of carriages moving by itself. His Excellency the Governor and the Garrison Commander had come to the station to wish me a happy end to my travels, and to see that I had everything I wanted. Let me be allowed here to express once more my lively gratitude!

Then followed two long days in the train across the wide plains of Kordofan, the crossing of the White Nile by a monumental bridge, then the arrival on the Blue Nile at Sennar, where passengers were waiting who had come from the Upper Nile; then Wad Medina in the afternoon, and finally, in the middle of the night, Khartoum.

I stayed a week in Khartoum, where I was the guest of the Civil Secretary, Feilden Pasha, and Dr. P. S. Crispin, Director of the Medical Service. It was an enchanting week that I spent in that pearl of the Sudan, which is already visited by many a tourist, so great was the consideration shown me by my hosts and by the high officials and officers of the capital.

I left Khartoum on August 24, arrived in Cairo in the morning of the 28th, and on the 30th had the honour of being presented at Alexandria by the French Diplomatic Agent to His Excellency the British High Commissioner in Egypt, Sir Reginald Wingate.

As there was no boat ready to start for France, I was able to satisfy my impatience to see an up-to-date fighting front by a visit to the British front lines opposite the Turkish trenches which at that time defended Gaza. Then, returning to Alexandria, I embarked for Malta. From there I reached Syracuse, and thence, by Messina, Naples, Rome, and Modane, I arrived on 1 October 1917 in Paris, and from there a few weeks later I joined the French front.

10. Conclusions.

Geographical Results.—In the course of this lengthy statement I have set forth in their respective places the principal geographical results obtained during the last five years of my stay in Central Africa; but it will perhaps be convenient to group them in a separate paragraph.

In the first place, the great geographical problem of ancient fluvial communication between the basins of the Chad and the Nile is definitely solved; the mountainous barrier encircles the basin of the Chad from the Toummo Mountains on the north to the Djebel Marra on the south-east, passing through the massif of Tibesti, the plateau of Jef-Jef, the tablelands of Erdi and Ennedi, the hills of Zagawa, and the mountains of western Dar Four.

In the second place, the lowest altitudes of the Chad basin are found in the plains of the low-lying region situated to the north-east of Lake Chad, which we have designated as “the Lowlands of the Chad.” The lowest altitude, of 160 metres (about 520 feet), was found in the ancient lake of Kirri, at a distance of about 250 miles from Lake Chad.

It is towards this low-lying zone that all the great valleys of the hydrographic system of the Western Sahara seem to converge. It is to be presumed that, such being the conditions, the tracing of a hypsometric curve of 250 or 260 metres of altitude (that is to say, slightly superior to that of the actual Chad) would fix the limits, in the region of the Chad, the Lowlands of the Chad, and Borkou, of the ancient Central African lake zone, the existence of which is proved by the agreement of the geological, topographical, ichthyological, malacological, and other observations made in these regions in the course of the last twenty years. Are we to see in the remains of this former Caspian of the Sahara the Chelonide marshes of the geographers of the ancient world? To do so would not be altogether unreasonable if it be taken into account that, so far as I am aware, there is not to be found in the south-west of the Lybian desert any other low-lying region combining conditions so favourable to the existence of a vast zone of lake or marsh.

Again, if we bear in mind certain local traditions declaring that towards the beginning of the nineteenth century native navigators were able to go in boats from the Chad to the Lowlands of the Chad by the Bahr el Ghazal (an assertion that the present appearance of Lake Kirri, recently dried up, makes sufficiently probable), one may conclude that until the early centuries of the Christian era this low-lying and now completely waterless region of the lowlands of the Chad may have been a great zone of lakes and marshes dotted with sandy or rocky archipelagoes.

Other facts may equally be noted in corroboration of this hypothesis. Firstly, the numerous layers of shells of river molluscs and the large quantity of fish-bones to be met with there: among the latter a fragment of a skull and vertebræ examined by M. J. Pellegrin, which he thought were to be attributed to a Nile perch (Lates Niloticus, L.) of about 6 or 7 feet in length (in the Comptes Rendus de l’Académie des Sciences, tome 168, No. 19, p. 963. Séance de 12 May 1919); and the discovery of an elephant skeleton in a region where neither grass nor water is any longer to be found. Attention might also be drawn to the rock-drawings of Yarda, where hippopotami are represented among horses, camels, dogs, and ostriches; or to the numerous ruins of settled villages found all up and down, especially where the Bahr el Ghazal falls into the Djourab. Lastly, it may be mentioned that on the platform of certain rocks in Borkou may be found great cemeteries that a native chief attributes to a completely vanished race of “black Christians.” But our researches revealed to us no trace or vestige of Christian religion, perhaps because we could not devote enough time to them.

A third important result has been to reveal the geographical form of important mountain masses like Tibesti and Ennedi, hitherto shown in a very imperfect fashion on the maps of Africa, and the existence of another important massif called that of Erdi, connecting the two above mentioned. Moreover, the information we received permits us to reveal to geographers the existence in the centre of the Lybian desert of yet another mountain mass, the Djebel El Aouinat, situated about 150 miles south-east of the oasis of Koufra, and of which the altitude probably exceeds 4000 feet.

A fourth interesting result has been the precise determination of the difference of longitude Paris-Faya by direct hearing of the wireless time-signals of the Eiffel Tower. Numerous rectifications of the positions attributed to various important points have resulted, the most notable being that which throws more than 50 miles to the N.N.W. the positions attributed by Nachtigal to Bardaï, the peak of Toussidé, the valley of Zouar, etc.

A fifth important result is furnished by the discovery in northern Borkou of the Harlania Harlani, which authorizes us to affirm the Upper Silurian age of all the sandstone sedimentary formations of Tibesti, Erdi, and Ennedi.

A sixth point will also, no doubt, be remarked by geographers: from the peak of Toussidé that dominates the north-west of the Tibestian massif to the Djebel Marra overlooking the plains of south-western Dar Four, that is to say, for more than 800 miles in a straight line, numerous hypsometric determinations have been effected which modify—sometimes by several thousand feet—the altitudes of the chief summits of the mountain chain that separates the basin of the Chad from that of the Mediterranean: in Tibesti, Toussidé, 10,700 feet instead of 8200, Emi Koussi, 11,200 feet; in Ennedi, the plateau of Erdébé, 4300 feet; in Tama, the peak of Niéré, 4700 feet; in Dar Four, the peak of Dourboullé, 7200 feet, the Djebel Marra, 9800 feet instead of 6000. These figures are given merely as an indication subject to the rectifications that will follow the revision now proceeding of the summary calculations rapidly effected during my journey.

Lastly, the establishment of the geographical liaison between the Niger, the Chad, and the Nile, by a chain of astronomical positions determined with very satisfactory exactitude, constitutes a seventh result, all the more interesting in that it will permit the drawing up of four sheets of the international map of the world, thanks to the 10,000 kilometres of surveys traced by my collaborators and myself during this long expedition.

From this geographical liaison allow me to pass to another kind of liaison and say a few words on a subject I have particularly at heart, and which is the conclusion not only of this five years’ journey but also of all the journeys I have had the opportunity of making in Central Africa since the beginning of the twentieth century,—I mean the importance, I will even say the necessity, of Franco-British collaboration in the great work of African civilization.

When I first set foot on the Dark Continent, in 1896, tropical and still mysterious Africa was a subject of discussions and rivalries between French and British colonials; but at the present time twenty years of fruitful emulation have ended in a definite and final division of our various possessions, and it seems to me that henceforth Africa is destined to be the tangible pledge of the union of our two countries.

I believe that in England as in France a considerable number of thoughtful men hold that it is above all to the African continent that we must look in a very large proportion for the supply of raw material and foodstuffs that we need. The question is whether it is more to the advantage of France and England to co-operate as closely as possible in developing these vast and practically unworked regions, or whether it is preferable for them to pursue this object separately, each country limiting its means of action to its own sphere of influence.

For my part, I hold that the answer is not doubtful: our two countries should unite their resources for a loyal collaboration in this essential work, so as to assure its complete success as rapidly as possible. I know that the problem is no very simple one; but have we not solved harder ones in the course of these last years, when for both our countries the question was “to be or not to be”? And since it would appear that the great and formidable economic struggle that is beginning on the morrow of the victory is destined to be as keen, if not keener, than the military struggle, it seems to me that the hearty, loyal, and complete union of our efforts can alone assure us of success.

The Trans-Sudanese.—It is an axiom henceforth beyond argument that the utilization of the riches running to waste in Tropical Africa cannot be seriously taken in hand until an adequate system of railways is constructed. Allow me, in bringing this lecture to an end, to explain what seems to me the most rational way of conceiving the general programme of the African railways north of the equator.

In the first place, we must endow Africa with a great transcontinental line from west to east, destined to ensure rapid communication between the different French and British colonies bordering on the Sudan. I have proposed for this railway the name “Transsudanese” (Comptes Rendus of the Academy of Sciences, vol. 169, p. 418. Sitting of 1 September 1919 (Gauthier Villars, Paris)); and its main lines, roughly indicated by the natural features of Africa, and following the 13th degree of north latitude, should include the following points:—

(a) Dakar and Konakry, starting-points on the Atlantic Ocean;

(b) Ouagadougou, Sokoto, Kano, Fort Lamy, Khartoum, crossing the French Sudan, British Nigeria, the French territory of the Chad, and the Anglo-Egyptian Sudan;

(c) Port-Sudan and Djibouti, termini on the Red Sea.

Secondly, along this “Transsudanese” would be formed junctions at the most suitable points, with local branch lines from the different French and British colonies that succeed one another along the Atlantic coast from the mouth of the Senegal to that of the Congo.

Thirdly, this railway system would be connected with the Mediterranean ports—on the east by the Nile valley railway from Khartoum to Cairo; on the west by a French “Transsaharian,” starting from the great bend of the Niger and connecting with the railway systems of Tunis, Algeria, and Morocco, and at some future time with that of Europe by a tunnel under the Straits of Gibraltar, or simply by train-ferry.

Among the many reasons urgently in favour of the construction of the Transsudanese, I will confine myself to stating what seems to me the most important and perhaps the least known, the question of labour. For it is generally agreed that the opening up of Tropical Africa cannot be undertaken without the large co-operation of black labour. Now, for long years to come four-fifths of that labour will have to be supplied by the Sudanese populations, much less wild and much less indolent than the great majority of the coast populations, and consequently better fitted to lend useful aid to European enterprises. This Sudanese population, which may be estimated at some fifteen millions at the lowest count, is spread over more than a million square miles (4000 miles from west to east from the Atlantic to the Red Sea, and 250 to 300 miles from north to south, between the 11th and the 15th degrees of north latitude).

To recruit workmen scattered over such vast distances and convey them without loss of time to the points where European enterprises are ready to employ them, it is evident that an unbroken line of railway must pass through the total length of the inhabited zone—that is to say, of Sudanese Africa. And it is of supreme importance that this railway should not have to take into account the political frontiers of the various colonies passed through, and that its one concern should be to traverse the regions in which the population is densest.

Such is one of the main considerations that fix the choice of the itinerary and bring me to the conclusion that the Transsudanese—a work of general interest in Africa, and more particularly a work of specially Franco-British interest—ought to be undertaken without delay, and pushed forward as actively as may be by the cordial co-operation of France and Great Britain.

These remarks do not apply to the local railways of the different colonies, though they may be expected to participate largely in the traffic of the Transsudanese, either by carrying down the products of the interior to the ports of the coast or by giving access to the regions in need of development, and in which Sudanese labour will be required. I am of opinion that these railways, limited as they are to the particular territories of the several colonies whose economic development they ensure, should continue to be constructed and managed, as hitherto, by the colonies they serve: those colonies should bear the expense of such local lines by their own financial resources, or by those placed at their disposal by the mother-country.

As for the Transsaharian, destined to connect the railways of North Africa (Morocco, Algeria, Tunis) with those of the Niger basin, I have had the opportunity of saying in another place that it has become a vital necessity of French colonial policy in Africa—a necessity that the great war has proved to demonstration. For this reason I hold that its construction should be regarded as a work of strictly national interest. Still, a glance at the map will convince the observer of the profit that will accrue to the British West African colonies, especially when it becomes possible to cross from Europe to Africa without the inconvenience of a sea-passage. I have often been met by the objection that the Transsaharian “will not pay”; that it will be almost exclusively a strategic railway, very laborious to construct, and very costly to keep in working order. Such is not my opinion. The Transsaharian, once the junction effected with the Transsudanese, will connect two exceedingly rich regions—the Africa of the Arab and Berber races and Black Africa. Between these regions a considerable commercial traffic will arise, which will have an influence as great or even greater than that of the Transsudanese itself on the economic development of Africa; its receipts per kilometre will be as large if not larger than those of the most favoured of the railways running from the colonies along the coast inland towards the Sudan, for the Transsaharian will be the direct means of penetration into the richest regions of tropical Africa, not only from North Africa, but also from the whole of Western Europe.

1871-1919

May I say one word about Tibesti and Borkou, and so conclude? Half a century ago, when Nachtigal, after exploring the Tibesti, came to the shores of Lake Chad, before setting out again to complete his work by the exploration of Kanem and Borkou, he learnt by letters from Tripoli the victories that his native country of Germany had won over France. And again, when he returned to Europe after four long years of absence, he found that peace had been made two years earlier, and that our provinces of Alsace and Lorraine had become part of Germany and were called the Reichsland; France, humiliated, was just finishing the payment to the conqueror of the milliards that were to hasten the liberation of her territory.

By a striking example of the way in which history sometimes repeats itself, but with a difference, war was once more forced on France by Germany at a moment when French explorers had just set foot in Borkou and Tibesti in order to rectify, revise, and complete the unfinished work of the German explorer! And the joy that filled the heart of Nachtigal when he returned to Europe to find his country triumphant, and her borders widened with the spoils of war, swells in our hearts to-day! For it is Germany now that knows the humiliation of paying milliards to obtain the liberation of her own territory, while the tricolour floats over Metz and Strasburg, and watch indeed is kept, but to other music, on the Rhine!

From this parallel, may I venture to conclude that in her treasure-house of colonial jewels France may well find a place for arid Borkou and the barren Tibesti. For would it not seem that they are, in some sort, talismans, and that when Gaul and German grapple on the banks of the great river that was set by nature and destiny to hold them apart, Fortune, that wayward goddess, shall give victory to whichever country has a son exiled in those mysterious regions, seeking, by rock and desert, new ways across their ancient sand?

[Translated from the French by W. G. Tweedale, M.A., Oxon.]

Before the paper the President said: It is a special pleasure to us to welcome here this evening that well-known French explorer and geographer, Colonel Tilho. We had been long hoping to have the pleasure of receiving him and of hearing an account of his recent journeys from 1912 to 1917, but owing to the press of official business he was not able to come here in the summer, and it is only by the greatest good fortune, and by the exercise of a little tactful pressure upon the different Governments, that he has been able to be present this evening. This is not the first occasion upon which he has been before the Society. He gave us a most interesting paper about ten years ago, so that he is not a stranger, and we are very glad to welcome him again. What he will describe to us this evening will be his journeys in Central Africa and the French Sudan between the years 1912 and 1917; and it was for the valuable work which he did during those journeys and for his general contribution to geographical knowledge that we awarded him, two years ago, our Patron’s Gold Medal. I have, therefore, very great pleasure in introducing Colonel Tilho to you and asking him now to address us.

Colonel Tilho then gave in French a summary of the paper printed above, and a discussion followed.

The President (after the paper): Sir Henry McMahon, who was High Commissioner in Egypt during part of the war, is present here, and we shall be very glad if he will kindly make some observations in regard to Colonel Tilho’s interesting lecture.

Colonel Sir Henry McMahon: We are much indebted to Colonel Tilho for a most interesting paper to-night. It is not only of very great interest, but a valuable contribution to geographical knowledge. I will leave the discussion of the lecture as regards its geographical and cartographical aspect to others, but there is one portion of the paper to which I should like to call your attention. As Colonel Tilho has told you, during the war the Germans and Turks got a footing in Tripoli. He has told you how Enver Pasha’s brother, Nuri Bey, landed on that coast, and with him many Germans. Their object was to get into touch with the Senussi; raise the whole country against us through the Senussi influence, and threaten our western flank both in Egypt and the Sudan. They very nearly succeeded; and if our brave allies, the French, had not forestalled them in the country described to-night, they would undoubtedly have established themselves there. It is a valuable objective as being the first place in which water and supplies can be got after leaving the oasis of Kufra. We will imagine for one moment that they had established themselves there. You can at once see what a dangerous focus of intrigue and unrest, what a source of danger it would have been on our flank all along our western front. Having forestalled the enemy there, no further trouble ensued, but our friend the Sultan of Darfur, who misjudged the time of the Senussi arrival and counted too confidently on their aid, had already started hostilities with us, and a war ensued which in times of peace would have attracted wide public attention but in the days when our interest was so concentrated on other fronts it almost escaped notice. Suffice to say that by a brilliant series of military operations, our troops, under the direction of Sir Reginald Wingate, the Sirdar of the Sudan, drove him out of his capital and took the whole of his country. If the Senussi had at this time been established with their German and Turkish assistants on our flank, it might have been a very different job indeed. I look upon this incident as an object lesson of the good that co-operation can effect in a work of this kind, and it is, I hope, not only an object lesson of what has been done in the past times of war, but an augury of what we can do and should do between us in the future times of peace. As Colonel Tilho has explained to you, co-operation is essential for the development of this great country of Africa, and I trust that it will be the guiding principle of our two great nations not only in the development of that country, but in furthering the welfare of the backward peoples placed under our guardianship.

The President: The French Military Attaché is present and we should be very pleased if he would kindly address us.

General the Viscomte de la Panouse: Je ne savais pas que j’aurais à prendre la parole ce soir en sorte que je me trouve un peu pris au dépourvu. Je vous demanderais donc la permission de m’exprimer en Français. Il y a quelques vingt ans, il eut été impossible de discuter ici dans une atmosphère de calme et de confiance mutuelle une question relative au centre du Continent Africain. Heureusement depuis cette époque, grâce aux bienfaisants accords de 1904, les malentendus entre le Royaume Uni et la France se sont dissipés, l’Entente Cordiale est née, elle s’est développée et elle a vu son couronnement dans une alliance militaire étroite et loyale pendant la plus grande guerre que le monde ait vue. Le Colonel Tilho vous a exposé pourquoi dans le développement économique de ce Grand Centre Africain, l’action unie des deux grandes Nations est nécessaire sous peine d’aboutir à un gaspillage inutile d’efforts et d’argent. Mais je vois aussi une autre raison pour laquelle nous devons travailler ensemble; l’Empire Britannique et la France ont lutté pendant cette grande guerre pour faire triompher les principes du droit et de la liberté contre l’oppression et la barbarie. Notre victoire nous a créé des obligations et en particulier celle de défendre les populations noires contre la tyrannie des marchands d’esclaves et de l’oppression des sectes musulmanes et de leur donner le bien-être auquel a droit tout être humain. Ce devoir ne sera utilement rempli que si nos nations s’entendent sur les mesures à prendre et les réalisent en commun. La belle œuvre d’humanité à accomplir sera ainsi un nouveau lien entre les deux Grandes Puissances qui se partagent le continent Africain.

The President: We have been fortunate to catch Sir Harry Johnston. He is one of our greatest authorities upon Africa generally, both Central and Northern. We should be very glad if he would make some remarks.

Sir Harry Johnston: I had the honour some years ago, just after the war had started, of showing you a somewhat similar map of Africa with railways designed on it partly by my own fancy, and I may say to a great extent by following French fancies too; for about that time I had been in the north of Africa, and had been allowed to pursue for a certain distance the tracing of the projected trans-Saharan railway, the progress of which was only stopped by the war. I conceived then the idea that it was of the highest importance to Western Europe that that line should be made, though I, like most of you, did not appreciate the influence on affairs that the submarine would have; but of course that conviction has been strengthened by the events of the war. Had we had the trans-Saharan railway in existence during the war we should not have suffered as much as we did from the loss of some of the most important materials for our industries caused by the interruptions of the sea routes, the destruction of steamers, etc. It is a matter of absolute necessity, I consider, that that trans-Saharan line should be made to link up the valley of the Niger with French North Africa, and further with Western Europe; because, as Colonel Tilho has pointed out, the channel between Tangier and the Spanish coast could be easily patrolled and kept free of submarines, and even crossed by train ferries. Then another point I should like to raise is as to the further exploration of those Tibesti highlands and the lofty plateaus that are connected with them on the north-west and south-east. Colonel Tilho did not mention in his discourse what he said to me privately, that he had found in some parts of that region, possibly Borku, fossilized bones of elephants. He has referred to the native legends and to the drawings on the rocks which point to the existence of hippopotami in regions now entirely devoid of surface water. He showed some of these engravings. They are very similar to rock drawings which can be traced right across the Sahara desert, exhibiting a fauna now completely passed away. One reason why Tibesti should be explored is, that we might find there the fossil and semi-fossil remains of a very extensive tropical African fauna, because that isthmus of high land between the south of Tunis on the north, and Darfur and the regions round Lake Chad on the south, seems to have been the principal route by which the fauna of Miocene and Pliocene Europe and the Mediterranean basin reached Tropical Africa. There are more and more indications that the Sahara desert to the west and the Libyan and Nubian deserts to the east were formerly under water, and therefore checked the progress of beasts and man across the Sahara into Central Africa; but this high ridge always remained well above the limits of such lakes, marshes, or inland seas. Tibesti was a well-watered region with at one time quite a heavy rainfall down to about twenty thousand years ago.

Before the war suspended such enterprises, the savants of France were exploring the wonderful sub-fossil remains of Algeria which revealed to us the existence there of a mammalian fauna resembling that of modern tropical Africa, of the region south of the Sahara. With that fauna were mingled in a very interesting degree creatures which at the present time are restricted to India. For instance, there was something so like an Indian elephant that it might be called the Indian elephant, existing almost down to the human period in Algeria. There was a wild camel, an equine resembling a zebra; there were gnus, hartebeests, oryxes, and other types of modern African antelopes; and there was a Tragelaph allied to the Nilghai; there was a huge buffalo with almost incredible horns—14 feet long—incredible were it not that its existence is proved not only by its fossil remains but by the drawings of primitive man. The Foureau-Lamy Expedition, I believe, found many of the dry torrent-beds of the elevated Ahaggar region choked with hippopotamus bones. There is everything to point to quite a recent and rapid change in the climate of the Sahara, which, well within the human period, was a region abounding in water derived from a heavy rainfall, and richly endowed with forest areas, as we may see from the remains of petrified trees. This will bring home to you what gains might come to science and to our knowledge of the evolution of life on this planet if we could only thoroughly explore the Sahara, and above all such regions as the Tibesti highlands.

Major Hanns Vischer: Just after I had crossed the Sahara, some years ago, I had the great pleasure to meet Colonel Tilho in Nigeria; and last time we met—I think in 1909—to celebrate our homecoming in Paris, we spoke of the work in Africa of our two respective countries. During my journey, and whenever I met the French in those regions, I was particularly impressed by the difficulties and privations these officers suffered so cheerfully. In Nigeria we had our railway, and we got frequent leave. As I remembered those isolated posts in the heart of the Sahara, while looking at the pictures we saw to-night, separated by hundreds of miles, rarely getting a mail or any provisions from the coast during those long years of war, when few boats went to the West Coast of Africa, I was filled with admiration for the work done by Colonel Tilho and his comrades. In the course of his lecture the Colonel showed clearly how necessary it is for us to co-operate in Africa, not only for the welfare of the native people but also for the very existence of our respective colonies. He has shown to us to-night how well we can complement each other. When that German-Turkish column advanced south across the desert, at a moment when we had sent most of our troops from Nigeria to East Africa, it would have been a hard thing for the people in our colony if the officers under Colonel Tilho’s orders, assisted by some native troops sent north from Nigeria, had not been able to arrest the enemy’s progress.

The President: I know you will all want me to congratulate Colonel Tilho on your behalf on the lucid, graceful, and humorous lecture he has given us this evening. There has been great talk about the co-operation between us and the French, and I think we might go a little deeper even than that. When we can get a French officer like Colonel Tilho over here in the flesh, and can hear from his own lips what he has done, when he shows us pictures of the kind of country he has had to make his way through, the kind of people he has had to make friends with: when we see all that, certainly we who have had to do similar work in other parts of the world—and probably you at home, even though you have not had that great pleasure and honour, must have a very deep fellow-feeling with him and his compatriots—we feel that there is something deep and common between us when we realize so vividly the work that they are doing, the difficulties that they have had to encounter, and the great work of civilization and humanization which they are carrying on in these far remote recesses of Central Africa. We have had to do the same things ourselves in other parts of the world. We see the results of our own efforts, and Colonel Tilho this evening has shown us what the French have done in opening out the great arid wastes of the Sahara desert and the French Sudan. What they have done and what we have done is good for the world as a whole. It has all been opened out gradually in the course of years, not only for the French and not only for the British, but for all nations. Therefore we here in England, we in this Society, will send forth a very hearty word of congratulation to the French, and especially to Colonel Tilho, for the great work which they are doing in Central Africa. He has made very important geographical discoveries, and has referred to new methods of geographical observation. Wireless telegraphy for the purpose of determining longitude is a comparatively new method, but one which is vastly valuable, because, as we who have tried to determine longitudes in far-away places know, in old days it was impossible to get the longitude at all exactly. We could get the latitude fairly accurately, within a few hundred yards, but longitude we could never get to within a few miles. Now by means of wireless telegraphy we are able to get longitude with almost complete exactitude, even in the heart of the French Sudan. Colonel Tilho has also made a slight allusion to another modern invention which I think in future will prove of great service, and that is the aeroplane. We shall hear more of that at our next meeting; but when you see those vast waterless regions, when you hear from Colonel Tilho of the enormous difficulty in getting across them with camels, then we see of what use the aeroplane might have been made for preliminary geographical reconnaissance. Those two inventions, I am certain, will be of enormous service to geography. I now wish on your behalf to tender to Colonel Tilho a most hearty vote of thanks for his lecture this evening, and also for his great kindness, at considerable personal inconvenience, in coming across from Paris to give us this paper.