436 
THE AFRICAN ASSOCIATION. 
only, as follows. From Cabra to Agadez, a scat- 
tered negro town, the houses built with reeds and 
rushes, eight days ; thence to Humbri, fifteen 
days ; from Humbri to Butoo, twenty or twenty- 
five days. Eastward of Butoo, the navigation of 
the river is interrupted by falls and cataracts, and 
little known ; but it is generally believed to be the 
Nile, or to fall into it. 
On the 17th November 1804, Mr Grey Jack- 
son, who had resided many years as a merchant at 
Mogadore, made a communication to Sir Joseph 
Banks, relative to Tombuctoo, derived from the 
information of persons who had visited or resided 
in that city. He declined mentioning their names, 
lest, in case of his return to Mogadore, he should be 
found to have committed himself by doing so. The 
substance of this letter was afterwards published, in 
an expanded form, as an appendix to Mr Jack- 
son's description of the empire of Morocco. The 
information has evidently been collected somewhat 
loosely, but it appears original, and is probably cor- 
rect in many of its features. 
Tombuctoo is situated on a plain surrounded by 
sandy eminences. It is twelve miles in circum- 
ference, but not surrounded by walls. The houses 
are spacious, and built in a quadrangular form, but 
have no upper rooms, and even no windows, being 
entirely lighted from the doors, which are wide and 
lofty. Ten miles to the south lies Cabra, the port 
