succeed in making their way to the Char-chan river across the gravel glacis and the belt, partly scrubby desert and partly bare drift-sand, which stretches south of the river.
The small colony of Nash-shahri (C. 3 ),
Astronomically observed latitudes. 1906-08. Yol-sai, Camp 110 (C.4)
The area surveyed in the N. W. corner of this sheet is confined to spurs of the main K'un-lun range, descending north of the Charchan river gorge, and to a portion of the gravel glacis near the gold pits of Khâdalik. For its delineation a number of trigonometrically determined stations and points from R. B. Lal Singh's work of 1913
Astronomically observed latitudes. 1906-08. Kara-tâsh Sai, Camp 106 (A. 1) . 1913-15. Khndalik, Camp 8 (A. 1)
recently re-established near a site abandoned for centuries, and Tatran (D. 2 ), an outlying portion of the Charkhlik oasis, are the only patches of permanently occupied ground within the area comprised in this sheet.
38° 20' 2"
38° 22' 12"
38° 37' 59"
were available, besides some peaks intersected at the close of Rai ltâm Singh's triangulation of 1906 ( see Appendix A, sub 69 x). Two latitude observations were also utilized.
The level assumed for the snow-line is quite conjectural and probably far too low, both surveyors having visited the ground very late in the autumn.
37° 52' 24"
37° 50' 18"
1913-15: Kizil-kum, Camp 14 ( hill-station, 5128, on sand-ridge, N.E. of Camp; B.4)
Tatlik-bulak,-Camp 19 (west end of base, rock near ravine ; D. 3) ... NOTES ON SHEET No. 27 (KHÂDALIK )
NOTES ON SHEET No. 28 (TURFAN)
The main routes passing through the central and the south-western portion of this sheet were surveyed in 1907. But most of these were followed again in 1914-15, and as much of the Turfan depression (B-D. 3) was then surveyed in detail on the scale of 1 mile to the inch and much fresh ground both to the north and south of it mapped, the greatest portion of the work now shown in this sheet belongs to the third expedition.
For the adjustment of the plane-table work, the position of the ' Yangi-shahr' of Turfan, falling near the centre of the sheet, furnished a convenient base. The value adopted for its longitude is 89°6'30", this being the approximate mean between the value chronometrically observed by Mr. Clementi (89° 6► 3") and that accepted in the 1906-08 map (89°7'). The longitude shown in our map for the town of Lukchun, 89° 41' 30", receives welcome confirmation from the value of 89° 42' 28" which Roborovsky's astronomical observations indicate for his meteorological station, established close to that important town.
The latitude observation of 1907, as shown below, agrees with Mr. Clementi's within 22 seconds. The traverse along the main road eastwards was adjusted on the position adopted for Hami, and the traverse to
the southwest on that of Korla. The shifting to the west which the latter position has under gone through erroneous adjustment of R. B. Lal Singh's triangulation in the Kuruktâgh, as explained in group I of Major Mason's Appendix A, has affected also the positions of Singer (No. 29. B. 2) and -Altmish-bulak (No. 29. D. 3) in the adjoining sheet, with corresponding discrepancies in longitudes for the routes which from the Turfan basin lead south to these two places.
In addition to the latitude observations recorded below, several others taken by Mr. Clementi on the main road and by Russian explorers have also been used.
The details in the Turfan depression have as far as possible been taken from the one-inch survey carried out by M. Muhammad Yakûb from December, 1914, to March, 1915. This extended over practically the whole of the cultivated area of the Turfan basin, from Yamshi in the west to Pichan (No. 31. A. 3) in the east, and included a great portion of the depression in the south lying below sea-level. For this detailed survey a base was measured near Kara-khbja (C. 3), and the longitude of this place deduced from that of Turfan 'New Town' (Yangishahr).
One of the features which invest the