XXVII. — Notices and Extracts from the Minute-Book of the Geological 



Society. 



1. Extract from two Letters dated Sierra Leone, June 3d, 1822; and Ba- 

 thurst, St. Mary's, Gambia, July 20th, 1822 ; addressed by Joseph Byerley, 

 Esq. to B. FaylCj Esq., and comjnunicated to the Society by Dr. Babington^ 

 President. [Read Feb. 21, 1823.] 



X HE hills round Sierra Leone are of granite, or rather of sienite-porphyry, 

 composed of olive-green felspar in huge masses, with occasional mica and tour- 

 maline. This rock decomposes, and forms a red loose aggregate which serves 

 to build with, and is of the colour of red brick ; the whole soil partaking of 

 this colour, and giving a fine bistre tint to all the scenery, which forms a 

 striking contrast to the great verdure of the v^'oods. The scenery is highly 

 picturesque and mountainous. Orange, lime, coffee, cotton, acacia, cocoa-nut, 

 banana, palm, and other trees in wonderful variety, form a fine shade over the 

 beautiful and romantic roads through the woods on the hills around. The 

 pine-apples grow wild in the woods, and are very fine and abundant. Fine 

 copal is brought by the natives from the interior, but it is not an article of 

 trade, owing to the high duties in England. The governor has a coffee farm 

 on the mountains, the scenery around which is very fine. In the fore-ground 

 are rude fragments of dark olive-green felspar. Behind are higher mountains 

 covered with woods that are always green ; in the front down the valley is 

 seen Sierra Leone, on its reddish brown soil, bounded by the mouth of the 

 river and the ocean. The huts of liberated Negroes lie scattered here and 

 there amidst the trees, adding greatly to the beauty of the scenery. 



At Gambia there is only sand ; but opposite to the town there are islands 

 of red decomposed granite, part of which resembles iron slag. At Goree the 

 rock is a fine basalt which takes a regular prismatic form, similar to the Giant's 

 Causeway. 



The castor-nut grows like a weed at Gambia ; and large supplies of its oil 

 might be obtained thence ; but the duties in the mother country are quite pro- 

 hibitory. 



