1849.] 



On the Snow-line in the Himalaya. 



291 



Having disposed of these preliminaries, which are essential to the 

 proper apprehension of the subject, I shall proceed to examine the data 

 from which the elevation of the snow-line is to be determined. In doing 

 this it will I think be more convenient for me, both for the northern 

 and southern limits, to explain first my own views, and afterwards to 

 follow M. Humboldt's authorities, and point out the errors into which 

 they have fallen. 



1 . Southern limit of the belt of perpetual snow. — In this part of the 

 Himalaya it is not, on an average of years, till the beginning of Decem- 

 ber, that the snow-line appears decidedly to descend for the winter. 

 After the end of September indeed, when the rains are quite over, light 

 falls of snow are not of very uncommon occurrence on the higher moun- 

 tains even down to 12,000 feet ; but their effects usually disappear very 

 quickly, often in a few hours. The latter part of October, the whole of 

 November, and the beginning of December, are here generally cha- 

 racterised by the beautiful serenity of the sky ; and it is at this season, 

 on the southern edge of the belt, that the line of perpetual snow is seen 

 to attain its greatest elevation. 



The following are the results of trigonometrical measurements of the 

 elevation of the inferior edge of snow on spurs of the Tresul and Nanda- 

 devi groups of peaks, made before the winter snow had begun in No- 

 vember, 1848.* 



Point 



Height as observed on face exposed to the East. 



Height on face 

 exposed to West 



observed. 



From Almorah, 

 (height 5586 ft.) 



From Binsar, 

 (height 7969 ft.) 



Mean. 



observed from 

 Almorah. 



No. 1. 

 2. 

 3. 



4. 



16,599 feet. 

 16,969 

 17,186 

 15,293 



16,767 feet. 

 17,005 

 17,185 

 15,361 



16,683 feet. 

 16,987 

 17,185 

 15,327 



15,872 feet. 

 14,878 



* These measurements make no pretension to accuracy, but are sufficiently good 

 approximations for the purpose for which they are intended. The heights are given 

 as calculated from observations made both at Almora and Binsar, to show in some 

 degree what confidence may be attached to them. The heights of Almora and Bin- 

 sar are, on the authority of Capt. Webb's survey; the distance of these places, which 

 is used as the base from which to calculate the several distances of the points ob- 

 served, was got from a map of trigonometrically determined stations obtained from 

 the Surveyor General's office. 



