| preceding chapter, for he says: »C'est l'ouvrage le plus important sur la géographie du Thbbet.' To speak only of the source of the Brahmaputra, which interests us at the present moment, we shall see that the Ta-ch'ing-i-t'ung-yü-eu is incomparably the best of the two, which was, however, impossible for de Rhins to know in 1889, as great parts of Tibet, represented on the Ta-ch'ing map, were then unknown, at any rate to the European geographers. But Klaproth had, on his map of Central Asia of 1836, almost entirely copied the Ta-ch'ing atlas, except the parts near the Indian frontier. On the Ta-ch'ing map Tibet especially had been filled up by the help of a number of Chinese itineraries. One of them, accomplished by MA CHAO YU, is mentioned in the Wei-tsang-t'u-chih or Toftografthical Description of Central Tibet. By his analysis of the Chinese map de Rhins arrives at the result that its value and reliability is very different in different parts of it. It is easy to agree with him from the extracts he gives of the text. Disregarding some mistakes, the description of the source of the Brahmaputra is, for instance, very good, whereas the Bongba country is very poor and difficult to bring into harmony with reality. De Rhins believes that d'Anville had been influenced by the documents of Goëz, Andrade, Bernier, Grueber and Dorville, Desideri and della Penna when he introduced some changes and improvements on the Chinese map for Western Tibet.' »Sur ses cartes de 1735 d'Anville n'a pour ainsi dire pas modifié les positions du Tengri nor et du Tarogh mtso, placé par environ 32° de latitude sur la carte des Tai Thsing; tandis que la modification considérable qu'il fit subir au tracé du Tsan po, sur sa carte de 1752, le força à reporter par près de 33° la position du Tarogh mtso ... d'Anville était excusable de traiter ainsi la carte des Tai Thsing et ne pouvait l'utiliser autrement, à une époque où l'on ne connaissait ni la géographie Chinoise, ni les itineraires chinois.» In how far this opinion is correct for the interior of Bongba we shall see later on. For the sources of the Satlej and the Brahmaputra both give practically the same topography and hydrography, although the Ta-ch'ing map is richer in names (Pl. VII). As was to be expected de Rhins finds often great differences between the maps of the Ta-ch'ing, d'Anville and Klaproth, but generally he regards them as belonging to one and the same type. The chief difference between d'Anville's and Klaproth's maps he finds depending on the fact that the latter had at his disposition the maps of Bogle, Turner, Manning, Rennell, Crawford and all the British officers between Rennell and Crawford. Further he was able to use all the maps of the Survey of India, Moorcroft's results and all the material from 1812 to 1836, when his map was published. Regarding Nain Sing's survey de Rhins has made the following interesting observation: »Dans la région des sources du Tsan po, Nain Singh n'a suivi aucun des deux itineraires chinois marqués sur la carte des Tai Thsing. Les quelques | | |
IIIFカラー高解像度
