48 GREAT TRIGONOMETRICAL SURVEY OF INDIA. 



pass, after which lie marched to Quetta and fixed the most conspicuous 

 hills around. During the following season war broke out with 

 Afghanistan and Captain Rogers Avas attached to the southern army, 

 but Mr. Price carried the triangles up to Quetta, and Mr. Torrens 

 extended them to the boundary of Pishin beyond. A good descrip- 

 tion of the Kachi plain lying between General Jacob's tower on the 

 British boundary and the mountains forms part of Mr. Price's official 

 report. The various pieces of triangulation completed by Captain 

 Rogers and his assistants comprised the following : 1st, the series 

 from Jacobabad to Quetta ; 2nd, the series from Quetta to Khelat ; 

 3rd, the series from Quetta to Kandahar : 4th, the triangles round 

 Kandahar and the Khakrez valley. 



It was not till near the end of the field season of 1879-80 that 

 the work of the Eastern Sind Series was resumed, when Captain 

 Rogers completed two double polygons spanning a direct distance 

 of 64 miles. In the following year the series was completed by 

 Colonel Branfill by four polygonal figures carried northwards, and 

 closing on to a side of the Great Indus Series. A chain of secondary 

 triangles was also successfully carried by Mr. Torrens across 

 Central Sind to Sehwan, on the Indus, to furnish points for the 

 revenue and topographical surveyors. 



On the northern confines of India the survey of the mountainous 

 districts of Kumaun and Garhwal (of which only a small area 

 remained to be done) had been in abeyance during 1875-76 so 

 as to enable the who^ strength of the party to be applied to 

 the Dehra Dun survey, which by that means was finished in 

 that season. In 1876-77 the Kumaun and Garhwal survey was 

 resumed under Mr. E. C. Ryall and also brought to a conclusion. 

 The winter had been exceptionally severe, and the spring and 

 early summer cold and wet : consequently this told much against 

 the surveyors, whose operations had to be conducted at an average 

 elevation of about 16,000 feet above sea-level; Mr. Ryall's highest 

 point of observation was 19,600, while Mr. Pocock executed 

 one plane table section at 19,000 feet. The snow-line was much 

 lower than usual, and owing to the inhabitants being thereby detained 

 in their winter homes long beyond the ordinary time, supplies were 

 very difficult to obtain. Mr. Ryall's triangulation is described below, 

 p. 50. To Mr. J. Peyton was entrusted the topographical survey of the 

 Byans valley, but here again the exceptionally unfavourable weather 

 proved a great obstacle to work. In July there were only five days 

 of clear blue sky, when the mountain features could be delineated, 



