OCR Text |
Show A 'NOTATIO~S AND ADDITIONS. 133 tinent depends in its lending traits on several plastic relations, which are usually among the latest to be discovered and unravelled. A new and excellent work of our friend, Carl Zimmermann, on the upper country of the Nile, and the eastern parts of Central Africa, has again brought these considerations very vividly before me. His new map shows in the clearest manner to the eye, by means of a particular method of shading, what is still unknown, and what, by the courage and perseverance of travellers of all nations- among whom our own countrymen happily hold an important place- has been already disclosed to us. It is a valuable service, and one which opens the way for farther advances and more comprehensive inferences, when persons, thoroughly acquainted with the existing, often widely scattered, materials- men who do not merely draw and compile, but compare, select, and, wherever it is possible, check and control the routes of travellers by astronomical determinations or position-undertake to represent graphically the results of the elements of knowledge possessed at the time. Those who have themselves given to the world so much as you have done, have an especial right to expect much; since their combinations have largely augmented the number of connecting points; yet I believe that when you executed your great work on Africa, in 1822, you could hardly have expected so many accessions as we have now received.n The knowledge acquired is, indeed, often only that of rivers, their direction, their branches, and the various synonyms by which they are called in dialects belonging to different families of languages; but rivers reveal to us by their course the form of the surface of the earth, and are at once the nourishers of vegetation, the channels of intercourse between men, and pregnant with unknown influences on the future. The northerly course of the White Nile, and the south-easterly course of the great Goschop, would indicate that a swelling of the ground separates the domains or basins of these rivers. We know, indeed, but imperfectly, how such a swelling or elevation may be connected with the mountains of Habesch, and in what manner it may be continued southward beyond the Equator. Probably, and this is also the opinion of my friend Carl Ritter, the Lupata mountains, which, according to the excellent Wilhelm Peters, extend to 26° S. latitude, 12 |