1923%20Memoir%20on%20Maps%20of%20Chinese%20Turkistan%20by%20Stein%20s

APPENDIX A
A SHORT SUMMARY OF, AND DISCUSSION INTO,
THE MERITS OF THE TRIANGULATION EXECUTED BY
RAI SAHIB RIM SING11 -4ND RAI BAIIADUR LBL SINGH,
SURVEY OF INDIA, DURING THE THREE EXPEDITIOKS OF
SIR AUREL STEIN, K. C. I. E., IN CHINESE TURKISTAN
BY
MAJOR KISNKETH MASON. M.C., R.E.
INTRODUCTORY
The triangulatiol~ tliscussed belo~r~ falls into nine groul)s, ck.,
(A)-On the T%xh-dumb;isl~ Pinrir, 1900-01 (Ram Singh).
(B)-In the neightourllootl of Moz-tagh-at% and the Little Kara-kul, 1900-01
(Rim Singh).
(C)-At Tash-nialik hill, 1000-01 (Rim Singh).
(D)-Near Tash-kurghin fort, 1906-08 (Ram Singh).
(E)-Sootlt ancl east of Khotan, 1900-01 (Ram Singh).
(F)-Prom Acbchan to Kapa, 1900-03 (R&m Singh).
(C+)-In t,he head\raters of the Surtung-IiAsh, 1908, (LS1 Singh).
{H)-Frorn Kapa to lat,ituile 39O 0', longitude 8!1°47,' 191:;-15 (La1 Singh).
( I )-Proln Astin-bu1a.k to Korla, 1913-15 (L21 Sinyh).
It must be ren~embered that at the time of these operations, with the exception of one
or t\ro points 011 the K'nn-lun mountains south of Kilotan, uo inter-
"£ triaugulatlo,i, secteel points, from which the observers eo111tl resect their positiolr, had
Lcen rigorously fist~l I>\. the Survey of Intlia; and that therefore the
relative acertlncj :~ntI \.LLIUL' 01' the triatrg~~lation are c1el)eudent on the rnerits of Calk. Deasv's
work, on \r.I~ic~l~ it is Inrgclj bart.tl.
On tlrtx 1':ilnirs there (,xistet1 :I To\v i)t>ints tisetl I J Colonel ~ TVauhope during the Pimir
Bourrclary Co~nnrissiou of 1S95, but tl~ry alone ur1.c insnfficieut for the ueeds of It. S.
Rim Sit1~11 st any one of Iris stations.
Deasy's and \I'RII~IOI)C's \vork \yere Loth eonnectecl intlirectly by resection to unu~arked
fised by the Sur\.ey of Intlia. Ntither of tlrese observers conlil be certain that he
sources ,,,,ssil,le r.rv,rl.
rrsectetl his own 1)osit.ions from the esact points observetl by the Surrey
trianRnlators, sncl Ltim Singli anil IJal Singh must hn\.e been in doubt
as to the exact stunn~its, fixed by Ilcasy and Wanhope, from which they
resected their own stations. In many c;lstAs t,he peaks eml>loyecl had been intersected from long
distances by baclIy formed triallgles anel were themsel\-es liable to some error.
TVaul~ope's \vork is known to hare bee11 accurate within a very fen sccouds, and the
regular work of Deasy is also good. Nevertheless, in nlany cases, the stations of the latter
have been fixeel I)y observed latitutles ant1 azimuths to distant peaks, determined previoi~sl~
by himself or Walthope, and the intersection of the aeimuthal my and the latitude parallel has
been very acute, thereby introducing a fu~ ther error.