N ow the ab o v e assumed position o f T om b u c to o , falls e x a c tly at the giv en distance from M o ro c c o through T a t t a j and 18 short o f that from F e z z a n (M o u r zo u k ) ; h u t 61 beyond that from T u n is . T h e coincidence therefore o f the three lines o f distance from the Gambia, from M o ro c c o and F e z z a n , may b e regarded as complete, since, in using the same rate n ear ly across the whole continent o f A fr ica , from C ape V e rd to E g yp t , a difference o f 18 miles on ly , arises. A n d hence, the p ublic mind may well be satisfied at present respecting this important position. W h ich so e v e r o f the two determinations may be right, is o f little consequenc e: but I hold it to be more prudent to adhere to that line which is the result o f computation in detail, and corrected as ab ov e , than to the lo n g lines g iv en in the aggreg a te, and in which there is more risk o f error. A n d thus I close the subject o f the position p f T om b u c to o ; plac in g it in latitude 1 6 0 30'y longitude 1° 3 3 ' east o f Greenwich. Something, however, is proper to be said, concerning the rate o f trav e llin g adopted on the present o ccas ion, as it differs materially from that a llowed on lon g lines o f distance, in the Proceedings p f the Asso ciation , in 1 7 9 0 . I there allowed 165- fo r a single day, but diminished the rate according to the len gth o f the lines o f distance. I t would appear that the proportion o f diminution allowed, although p rop e r enough in countries, where obstacles interpose to change the line o f direction, is not applicable to that part o f A fr ica , where the great Deserts are crossed in so straight a line, as hardly to increase the simple winding, arising on each d a y ’ s course, in any considerable degre e ; and that ev en the simple winding is less than elsewhere. A n d hence o r more, arises on the camel routes, on long lines o f d istance, across the D e s e r t ; and on the pilgrims’ routes, where it appears the camels travel with light burthens. I t was through misconception o f this rate, that I placed T om b u c to o , so far to the north.. I am igno rant o f the cause o f M . D ’A n v ille ’s error. T h e particulars o f the geography between Silla and T om b u c to o , are co p ied e x a c tly from M r . P a rk ’s m ap ; and require but little elucidation, ¡in n é , a large town, is two short jo u rn ie s below S illa : and T om b u cto o , twelve still low e r down. I t would appear that all the journies were conc e iv ed to be short, as M r . P a rk allows on ly 200 G . miles for the aggregate o f the 14 . T w o days b e low J in n é , the Jo lib a expands itself into a considerable lake, already mentioned b y the name o f D ib b ie ; from whence the r iv e r again issues in a number o f streams. T h e se unite at a low e r point, and then form two large branches, which separating widely from each other, form an island near 100 miles in length, whose name be in g G in b a la , o r Jinbala, we re co gn ize in it, the Guinba la country o f M . D ’A n v ille ; as in the northern branch o f the riv er th a t bounds it, the r iv e r o f G u in , mistaken b y him fo r the original head o f the T om b u cto o r iv e r (or N ig e r ) ; as he also mistook the lake o f Dib b ie for that o f the Senegal r iv e r. Su ch w e r e the errors in the A fr ic a n geography, to thè date o f the A f r i c a n A s s o c i a t i o n : one o f which errors conducted the Senegal river through 500 miles o f the space ■which is, in reality, o ccupied b y the N ig e r . T h e position o f Hou ssa will be adjusted in the map o f A fr ic a . T h e important station o f T om b u cto o , being adjusted, together with the positions dependent on it, I proceed with M r . P a rk , on bis return b y the south, to his original point o f outset in the west : taking it up at S e g o , b y which he passed in his wa y. A lo n g this line, an a c co u n t o f the bearings b y compass was k ep t, as well as circumstances w ould permit, until the instrument was rendered useless, b y robbers, near S ib id o o lo o . T h is was, howe v e r, the most important part o f the route, as it la y along the side o f the J o lib a , the knowledge o f w hose course is, b y this means, prolonged to ab out 350 British miles. M r . P a rk moreover committed to paper, a tracing o f its general windings ; and o b tained notices respecting the p la c e o f its source, durin g his long residence a t Kama liah, in the country o f Manding, (commonly called Mandinga.) Kamaliah is ab out 40 G . miles S W o f S ib id o o lo o ;* and to this p lac e M r . Pa rk contrived to extend his line o f bearings from Sego . H e also learnt, that Jarra la y ten jo u rn ie s to the north-westward o f K ama liah ; which agrees satisfactorily to the result from Sego , as it lea ves 1 5 4 G . * It lies nearly midway between the Joliba and Senegal rivers, f 2
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