CHAPTER XIV. 
SURVEY WORK OF THE EXPEDITION—BY R. S. CLARK. 
HE Map* accompanying this volume is based on the plane-table work 
carried out by Hazrat Ali, of the Survey of India, the ill-fated member 
of our party, whose death at the hands of the Chinese near Lan-chou brought 
the expedition to an untimely close. A short description of the means and 
methods employed on the survey will, we trust, be found of interest. 
Commencing with a list of the instruments used, and remarking 
where necessary as to their pattern etc., we give a few notes to indicate 
briefly the methods employed for fixing our base, for carrying out the whole 
survey and for determining certain check-measurements; finally connecting 
up the results of our work with such records of previous surveys as are 
available. For the benefit of future travellers itineraries of the routes 
traversed are given in Appendix I., together with a table containing Latitude, 
Longitude, and—in most cases—Altitude of every important place visited. 
Instruments, etc. 
The instruments and appliances used were :— 
1 3-inch Astronomical Field Telescope. (Cary London) 
2 5-inch Micrometer Theodolites. (a aa) 
3 Half-Chronometer Watches. (Blockley, Kew certificated) 
1 Half-Chronometer Watch with Chronograph. 
3 Aneroid Barometers. (Cary) 
1 Boiling-point Thermometer. (Se) 
1 Georges Mercurial Barometer. (5S) 
I 100-foot Invar Tape. 
1 Plane-table. 
t Road-wheel. 
Base-lines. 
(A) As described in Chapter I, the party went into camp a few 
miles out of T’ai-yiian Fu to measure a base-line, the site chosen for 
* Ina pocket at the end of volume. 
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