x l T h is naturally leads me to the discussion o f the position o f F o r t St. Jo seph , as a point connecting the upper and lower part o f the Senegal r iv e r : o r in other words, the routes o f the F rench, below, with those o f the English, in the inte rior o f the country. T h e F rench repor t concerning this position also points to an excess o f distance from the wes twa rd; even more than that arising from the difference between M r . P a rk ’s re ckon in g and the reports o f the merchants; fo r it amounts to about 3 7 miles. C o u ld it be ascertained that a measured surv ey o f the Senega l r iv e r , to the height o f F o r t St. Joseph, had been taken, as Lab a t says (V o l. ii. p. 1 5 7 .) was actua lly done, b y the order o f the Sieu r Br iie , this would settle the matter at on ce . B u t cursory surveys h av e so often been called actual and measured ones, that one must be in possession o f better authority, before the survey o f the Senegal riv er can be relied on, as an absolute measure o f distance. N o r is there, in the list o f places in the Con. de Temps, any intimation o f the longitude o f St. Joseph b y triangles, or measurement. Here follows a statement o f the means used in fixing the position o f this place. M . D ’A n v ille , in his map o f the Senegal and Gambia rivers ( 1 7 5 1 ) places St. Joseph 70 4 4' east o f F e r ro , which being in 17 ° 3 7 ' west o f Greenwich, F o r t St. Joseph should be in 9° 5 3 '. T h is is 32' to the west o f the position arising on M r . P a rk ’s route ¡ which gives 90 s 1'. B u t M . D ’A n v ille supposes a difference o f longitude o f 6° 9 ' 1 5 " on ly , between F o r t St. L o u is , at the mouth o f the Senegal r iv e r , and F o r t St. Jo seph : and as I have fo llow ed M . F leu r ieu ’s ideas in placing St. L o u is in 16 0 8' longitude, St. Joseph o f course falls in 90 5 9 ', rejecting the seconds; making a difference o f 37 ^'■ miles, or 38 min. from M r . P a r k ; that is, 13 miles more than the mean o f the differences between the authorities for the position o f T om b u cto o .* * It is proper to remark that M. D’Anville took the longitude o f Cape Verd, 18J min. more to the east, in respect of Ferro, than M. Fleurieu: and Fort St. Louis more to tlie west in respect to Cape Verd, by io| min. M. D ’Anville moreover, allows no more than 3° 2' 30' diff. Ion. between Pisania and Fort St., Joseph, which by the corrected distance of Mr. Park, is no less than 30 42’. I t is obvious , that as neither S t. L o u is n o r Jillifre y , are e x a c tly determined, in respect o f Cap e V e rd , o r o f each other, it would b e idle to attempt a cr itical adjustment o f th em ; and therefore I have adopted the position arising from Mr. P a rk ’s route, corrected b y 24 miles, o r 25 min. o f longitude, more to the wes t; so that F o r t St. Joseph stands in the map in Ion. 90 4 6 ', lat. 14 0 34' In consequence o f this correction, all the eastern positions, J o a g , Ja rra, Sego, & c . must o f course recede 25 minutes to the westward o f the arrangement heretofore made, on the construction o f M r . P a rk ’ s geographical materials. H en ce I place J o a g , in 90 3 7 ' west, instead o f 9° 12 ' Ja rra, in 7 13 — ■ ■ 6 48 S e g o , in 2 26 - 2 1 Silla, in 1 24 o 5 9 A n d T om b u c to o in 1 33 east, ---------- 1 5 8 * I now proceed to state the reports o f the distance to T om b u c to o , from the N W , N , and N E . F rom T a t t a f on the southern frontier o f M o ro c c o , journ ies to the S S E o f the capital, (equal to 1 5 7 G . miles) the distance is 50 jo u rn ie s o f the caravan, a c co rd in g to M r . Ma tra . F rom M o u r zo u k , the capital o f F e z z a n , (taken to be in latitude 2 70 4 8 ' and longitude 15 ° 3' east, o r directly south o f Mesurata), 64 jo u rn ie s , a ccording to ' the report o f B en A l i . A n d from T u n is , 7 7 jo u rn ie s , through Kab e s and Gadamis, according to M r . Magrah. O n the route between M o u r z o u k and C a iro , as well as between M o ro c c o and Jarra, it has been already stated (p. x x x v i ii) , that 16 ,3 and 16 ,2 5 were the mean ra te s : and the former was accordingly adopted between W o o l li and Sego . A t the same rate, the 50 days from T a tta , g iv e 8 15 G . miles, and the 5 9 I from M o ro c c o , 9 70 . T h e 6 4 from M o u r z o u k give 10 4 3 ; an<^ the 7 7 from T u n is , 1 2 5 5 . • The latitudes remain as they were. t For further particulars respecting Tatta, see Afr. Assoc. Ch_; p. 225: and O. 333. f
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