CONCLUSION. 28d 



•f the earth is composed. Lastly, when it is known that 

 hot springs are intimately connected with subterranean 

 igneous agency, — that power which formerly acted so ex- 

 tensively in fonnin'g and modifying the rocks of which the 

 crust of the earth is composed, and which even now con- 

 tinues, although on a less extensive scale, to occasion con- 

 siderable changes on the surface of the earth, — their natural 

 and chemical history becomes very interesting from the 

 light they shed over many important geological phenomena. 

 Geology of Caffraria^ Natal, <^c. — The geology of the 

 countries of Calfraria and Natal is entirely unknown. In 

 Sofala there are said to be mines of silver ; and gold is col- 

 lected from the sands and gravels of some districts. The 

 kingdom of Monomotapa, as it is called, at the distance 

 inland of about forty days' journey from Sofala, affords gold, 

 topazes, and rubies. The geology of the country from De- 

 lagoa Bay, in lat. 26° S., to Cape Delgado, in lat. 10° S., 

 is unknown ; a small quantity of gold-dust is collected in 

 it. From Cape Delgado to the equator, the country which 

 is under the dominion of the imam of Mascat, is unknown 

 in a geological point of view. The country from the 

 equator to the Straits of Babelmandeb has never been 

 visited by any geologist. 



CONCLUSION. 



From the preceding details it results, 



1. That of all the quarters of the globe, Africa has the 

 most truly tropical climate. 



2. That notwithstanding its nearly insular form, its ex- 

 tent of coast is much less in proportion to its area than in 

 the other quarters of the globe. 



3. That the peculiar condition of the hmnan species, the 

 distribution and even the aspect of the lower animals and 

 plants, and many of the characters of the African climate, 

 are connected with its comparatively limited extent of sea- 

 coast, its extensive deserts, and arid soil. 



4. That from the maritime situation of Sierra Leone and 

 its colonization by Britain, and the connexion of the southern 

 parts of the Great Table-land with the British settlements 

 on the southern coasts of Africa, we may conjecture that the 

 civilization of the negroes (if that interesting race be not 

 destined to extirpation, as has been the fate of the abori- 



Bb 



