国立情報学研究所 - ディジタル・シルクロード・プロジェクト
『東洋文庫所蔵』貴重書デジタルアーカイブ

XXIV

?

4

existence of this lake, erroneously attributed to Andrade the merit of having discovered the lake forming the source of the Ganges and the rest of the great rivers

of India. Even in our days there exist geographers who, without any shade of foundation, suppose Andrade to have discovered Manasarovar and to have penetrated through Tibet to China. In his own writings there is not a single line to such effect. By others he has, again with as great injustice, been called a swindler.

In 1661 and 1662, a memorable journey was effected by Grueber and Dorville from China through Tibet to India. I have related this voyage in Vol. IV of this work, to where it chiefly belongs. If we pause for a moment at the last mentioned epoch looking back over the past, we must admit that Europeans' knowledge concerning Tibet was still insignificant, although Odoric, Grueber, Dorville and Andrade had completed their journeys as well in the interior of that country as through the whole of its extent.

The next part of the first volume of my work embraces the cartographical history of Tibet. Considering the nature of the subject, it is obvious that we must here pass on from general views to details. On the oldest maps of which mention can be made in this connection, it is as much as the name of Tibet has been barely put down. Later on it is roaming about here and there through the regions North of India, and it is first in times far advanced that this realm, so narrowly engirded, begins to take shape also on the map. In order to be enabled to follow the course of this development, and to see how Tibet slowly appears as if growing forth on the map until it finally forms a sharply defined geographical conception, we must go back as far as to the middle of the 15th century. But it is first from the year 1700 that, by application of the method of the State Librarian Dr E. W. Dahlgren, we can try to disengage certain types. For prior to this period, Tibet merely existed as an accessory detail, a name on the maps, playing no active part. From the year 1700, the image on the map is more and more consolidated, developed and refined, until it gains the appearance which is represented on the million-scale map belonging to this work. Within the range of this period of more than 200 years, we can leave the ordinary i. e. the general maps of the whole of Asia, and pass to the detailed maps of Tibet and its special parts. There we can follow the course of development of the cartographical representations of the lakes Manasarovar and Rakas-tal, of the sources of the Indus, the Satlej and the Brahmaputra, and of the mighty mountain-masses to the North of the valley of

the Tsangpo.

I commence with the world map of the year 1447 and Fra Mauro's of the