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

(F)—FROM ACHCHAN TO KAPA, 1906-08 (RĀM SINGH)

(i). (Vide charts 60H, and L)

A base was measured near Achchan with a subtense bar, and the latitude and azimuth
observed astronomically. The position of 'C' h. s. was directly computed relatively to the
extremities of this base. The latitude of 'C' being thus determined, its longitude was de-
rived from observations at it to Pks. 1 and 2/60L previously fixed by Captain Deasy. Iden-
tification of the peaks was roughly checked by the two latitude results at 'C', which differed
by 50 seconds from Deasy's value. The value derived from the astronomical observations has
been accepted.
With the exception of stations 'G', 'J' and 'M', which were fixed by resection, the
triangulation connexion to 'O' h. s. is continuous, straightforward and reliable.
(ii). (Vide charts 69C, D, G, and K)
The connexion between 'P' and 'O' h. s. was distant and unreliable, and has been
obtained as follows. This link is weak.
At 'S' h. s. the latitude and azimuth to Pk. 2/69D (of Deasy) were observed astro-
nomically and the distance computed. An azimuth was also taken to Pk. 38/60L and from
these two peaks the longitude of 'S' was derived. It was found that these values differed
by about 8 minutes. The longitude of Pk. 2/69D of Deasy was based on two chronometer
observations, which were not in accordance, and which differed by some 15 minutes of arc:
it was therefore decided that though Pk. 38/60L is a far more distant peak, the longitude
derived from it is in all probability much the more accurate, and this value has been accepted.
'S' h. s., being now in terms of the triangulation previously computed, the positions of the
stations in its neighbourhood, of 'P' h. s., and of 'T', 'U' and 'V', were directly derived
from it, with the exception of the last named, which was fixed by resection.
(iii). A rough check for latitude was furnished by Rām Singh's observations. In
1900-01 he observed an astronomical latitude at the village of Niya. His value is
37° 4′ 13″. This station is roughly a furlong north of a triangulation station of his work in
1906-08, which he fixed by resection from Pks. 28, 35, 38/60L and for which he obtained a
latitude of 37° 3′ 34″.

(G)—ON THE HEADWATERS OF THE YURUNG-KĀSH, 1908 (LĀL SINGH)

(Vide charts 61A, and E)

Towards the close of Sir Aurel Stein's second expedition, a little triangulation was
effected by R. B. Lāl Singh on the upper Yurung-kāsh. At only three stations were the
observations sufficient to determine their positions by resection:
Seghizköl, 'A' h. s., was fixed by observations to Pks. 4, 25 and 31/61E, previously
fixed by Captain Deasy.
Zailik, 'D' h. s., was similarly fixed with reference to Pk. 1/61A, of the G. T. Survey,
Pk. 2/61A, of Rām Singh's previous work, and Pk. 8/61A of Captain Deasy.
Tār-köl, 'E' h. s., was fixed by observations to Pk. 8/61A, and Pks. 4 and 6/61E of
Deasy.
The heights of these stations derived from the mean of two observations are very dis-
cordant, the differences being 194 feet, 748 feet, and 924 feet respectively. These discrepan-
cies throw great doubt on the observations and the positions laid down for them should be
treated with suspicion.

(H) and (I)—KAPA TO KORLA, 1913-15 (LĀL SINGH)

1. General.—The triangulation is considered in two sections, firstly, (H), from Kapa
via Charkhlik to Pk. 1/75E, (i.e. from latitude 37° 20′, longitude 85° 35¼′, to latitude 39° 0′,
longitude 89° 47′); and secondly, (I), from Āstin-bulak, (latitude 40° 47′, longitude 90° 19′)
to Korla (41° 44′ 20″·8, 86° 10′ 10″·4). The sections each comprise about 300 miles of
work and are separated by the Lop desert.