OBSERVATIONS ON THE COURSE OF THE DHIOLIBA AS TRACED FROM COUROUSSA TO SEGO AND DJENNÉ.
The course of the river, from Couroussa to Sego, as I have traced it, deviates from the hitherto received opinions;[60] and I am bound to justify so material a change, when submitting it to the judgment of geographers. In laying down the routes of M. Caillié, I was not prepared for such a result, or rather I was apprehensive of finding former conjectures relative to the much more westerly position of the river, and of the towns through which it flows destroyed by actual observations, as an illusion is dissipated by the clear light of truth. It has however proved quite otherwise, and this opinion was far from rash. In fact, beyond Couroussa the river runs due N. E., then eastward, and afterwards for a great distance to the north, instead of pursuing invariably an eastern direction as marked upon the maps. But on what is this latter direction supported? On what foundations does it rest? It has no other cause than the position arbitrarily assigned to Timbuctoo, much too far east, much too far from the mouth of the Senegal. On the more modern maps attempts have, it is true, been made to remove this position farther west; the necessity of bringing it nearer to the ocean has been felt,[61] but it has not been advanced far enough, and has still been retained in nearly the same parallel, instead of being brought at the same time farther north.
If the objection be admitted that M. Caillié has carried his route by water too far west, the result would then be that his route from Timbuctoo to Fez must have been carried too far east: now these two results are opposed to each other, since it is the same line of route, and the same bearing, which lead from Couroussa to Sego, from Sego to Timbuctoo, and from Timbuctoo to Fez.
One powerful consideration is that M. Beaufort has fixed and ascertained the position of the town of Elimané, eastward of Bakel, by a great number of observations; this is the present capital of Kaarta. From that place travellers are daily going to Sego; our unfortunate countryman was himself on the point of proceeding thither, and would have done so but for the destitution caused by the pillage of which he was a victim, and which compelled him to turn back. He was then told that Ségo was only at ten days’ distance; that the bearing of Elimané with regard to Sego was E. S. E.; and that these days’ journeys were journeys on foot. Let us work on these data, and see whether they confirm the course of the river drawn from the itinerary of M. Caillié.
Can these days’ journeys be computed at more than twenty-one geographical miles? This can scarcely be admitted; but should they even be extended to twenty-two miles and in a direct line, it would be on the whole two hundred and twenty miles, which in the above direction would not reach the ninth meridian west of Paris.
While M. Caillié was at Kiebala, he was told the distances and bearings of Sego, which differ very little from the position resulting from that of Elimané in the opposite direction; and if the river was here carried eastward, as it is found in all the maps calculated from Park’s travels, there would no longer be any agreement between these two different sources of information. If, on the contrary, these respective data are preserved, they naturally harmonize, and the northerly course of the stream is confirmed.
Besides, the latitude of Sego, although not yet observed, cannot greatly differ from that of Sami, which is near it: the observation there made by Mungo Park gives thirteen degrees seventeen minutes, and this is perhaps, a little too northerly. The approximative position of Sego, resulting from various data, and which I have adopted as a medium, would thus be, latitude thirteen degrees; longitude, nine degrees west.
Sego, according to the itinerary, lies due north by the needle of Badiarana, that is north seventeen degrees west. This direction exactly passes through the position which I have assigned to Sego, from the observation of Sami, by Mungo Park.
The bearing of Sego is likewise precisely indicated by the N. N. W. line of the compass, drawn from Saraclé.[62]
The course of the Dhioliba, from Sego to Jenné, west and east, and the position of Sego, are still more strongly confirmed by data with which the traveller was furnished at Bamba. Sego is three days’ journey N. W. of that place; and at noon on the fourth, the city of Sego is reached: these are long days’ journeys. The proportion of three to four, or rather of three to three and two thirds, will be actually found as I have traced it.