CONFORMATION OF COUNTRY. 583 



into Africa, either for the advancement of scientific knowledge, or 

 for the purposes of trade or benevolence. In the case of the east- 

 ern ridge, we have water carriage, with only one short rapid as an 

 obstruction, right up to its base ; and if a quick passage can be 

 effected during the healthy part of the year, there would be no 

 danger of loss of health during a long stay on these high lands 

 afterward. How much farther do these high ridges extend? The 

 eastern one seems to bend in considerably toward the great falls ; 

 and the strike of the rocks indicating that, farther to the N.N.E. 

 than my investigations extend, it may not, at a few degrees of 

 latitude beyond, be mOre than 300 or 350 miles from the coast. 

 They at least merit inquiry, for they afford a prospect to Europe- 

 ans of situations superior in point of salubrity to any of those on 

 the coast ; and so on the western side of the continent ; for it is 

 a fact that many parts in the interior of Angola, which were for- 

 merly thought to be unhealthy on account of their distance inland, 

 have been found, as population advanced, to be the most healthy 

 spots in the country. Did the great Niger expedition turn back 

 when near such a desirable position for its stricken and prostrate 

 members ? 



The distances from top to top of the ridges may be about 

 10° of longitude, or 600 geographical miles. I can not hear of 

 a hill on either ridge, and there are scarcely any in the space 

 inclosed by them. The Monakadze is the highest, but that is not 

 more than a thousand feet above the flat valley. On account 

 of this want of hills in the part of the country which, by gentle 

 undulations, leads one insensibly up to an altitude of 5000 feet 

 above the level of the sea, I have adopted the agricultural term 

 ridges, for they partake very much of the character of the oblong 

 mounds with which we are all familiar. And we shall yet see 

 that the mountains which are met with outside these ridges are 

 only a low fringe, many of which are not of much greater altitude 

 than even the bottom of the great central valley. If we leave out 

 of view the greater breadth of the central basin at other parts, and 

 speak only of the comparatively narrow part formed by the bend 

 to the westward of the eastern ridge, we might say that the form 

 of this region is a broad furrow in the middle, with an elevated 

 ridge about 200 miles broad on either side, the land sloping thence, 

 on both sides, to the sea. If I am right in believing the granite 



