National Institute of Informatics - Digital Silk Road Project
Digital Archive of Toyo Bunko Rare Books

He states that in commencing his reconnaissance from the Kuen Luen Mountains (which he carried
on with the plane-table only), one of the three trigonometrically fixed points on which his work was
based, turned out subsequently to have been incorrectly projected on his board. This, together
with the doubt that must always exist when rapidly passing through an unknown country as to
the identity of the different peaks visible from the line of march, is quite sufficient to account for
the discrepancy. In my preliminary map I have assigned to Khotan a longitude of 79° 59′
instead of 79° 26,′ the position it has recently occupied on our maps. About its latitude there
can be no doubt. Mr. Johnson took several observations there with a 14-inch theodolite and
obtained a mean result of 37° 7′ 35″, whilst from Kishen Sing's observations with a sextant
extending over nearly a month we have a mean result of 37° 7′ 36″. The points east of
Khotan, i.e., Keria and the Sorghak gold fields, are derived from Kishen Sing's route survey,
combined with his latitude observations. We also have from the same source a complete survey
for the first time of the road viâ Polu to Noh, and thence to Leh. As a specimen
of the accuracy of this Pundit's work I may mention that when the road from Karghalik
to Pal, a distance of 630 miles, was plotted out on the scale of 2,000 paces to the mile, without
any correction or adjustment whatever (although 4½° were added to each magnetic bearing
in order to allow for magnetic variation) starting from my own value of Karghalik, the plot
closed at Pal (fixed by the Great Trigonometrical Survey) almost absolutely correct in latitude
and only eight minutes out in longitude, and in no single portion of the whole route, which
passes over elevations exceeding 17,000 feet in height, did the plotted value differ by as much as
three miles from his own observed astronomical latitude (vide Appendix Section A.). Of this discre-
pancy of eight minutes in longitude it is possible that a portion may be due to error of position
in the starting point (Karghalik), but it may be noted that the amount is no more than would
be accounted for by an error of 1¼° in the assumed value of magnetic variation. It is not
to be supposed that such accuracy is generally attainable, but in the present case, although the
surveyor laboured under certain disadvantages from the absence of inhabitants, yet there were
the compensating advantages that he was under no necessity for concealment; he was there-
fore able to take and record bearings when and where he pleased.

As regards the work executed to the north-east and east of Kâshghar; the position of
Maralbashi, on the road to Aksu, was fixed in latitude by Captain Biddulph (vide Appendix
Section A.), and its position in longitude is roughly determined by a few bearings, and esti-
mated distances taken by him on the road from Kâshghar.

On the road to Ush Turfan I carried on a rough route survey wherever I went, and took
observations for latitude and obtained chronometric determinations of longitude as far as Ui
Bulâk, in latitude 40° 26′ north and longitude 77° 36′ east. Thence by route survey I got a deter-
mination of the position of the Belowti Pass; calculating from this the probable position of Ush
Turfan I place it about three-quarters of a degree to the east of the position given it in the last
edition of Colonel Walker's Turkêstan map. On examining the latest Russian map (1873)
it appears that the position of Ush Turfan has been recently altered, and placed very near
where I would myself locate it. I have therefore in my map adopted the last Russian values of
Ush Turfan, Aksu, and all places to the east. It will be found that the cities of Aksu and
Kuldja are more than twenty miles to the east of the places assigned them in all but the most
recent maps.

The details inserted to the north of the map are taken almost exclusively from the Russian
topographical map of Central Asia (corrected to 1873). The portion of ground to the south
of Khokand, visited by Mr. Fedchenko, is derived from various maps purporting to be by that
distinguished traveller, amongst others, one recently sent by Madame Fedchenko to Colonel
Walker, differing materially from all others that I have seen. For the country between the
Alai, visited by Mr. Fedchenko on the north, and the scene of our own explorations in the
Pamîrs on the south, the map is compiled from all the limited sources available* which have