July, 1849. LEAVE TUNGU. ARRIVE AT CHOONGTAM. 95 



the dislocation is continued to a great depth into the sub- 

 stance of the rock. 



Large silky cushions of a forget-me-not grew amongst 

 the rocks, spangled with beautiful blue flowers, and looking 

 like turquoises set in silver: the Delphinium glaciate* 

 was also abundant, exhaling a rank smell of musk. It indi- 

 cates a very great elevation in Sikkim, and on my ascent far 

 above it, therefore, I was not surprised to find water boil 

 at 182° 6 (air 43°), which gives an altitude of 16,754 feet. 



A dense fog, with sleet, shut out all view ; and I did not 

 know in what direction to proceed higher, beyond the top 

 of the sharp, stony ridge I had attained. Here there was 

 no perpetual siioav, which is to be accounted for by the 

 nature of the surface facilitating its removal, the edges of 

 the rocks which project through the snow, becoming heated, 

 and draining off the water as it melts. 



During my stay at Tnngu, from the 23rd to the 30th of 

 July, no day passed without much deposition of moisture, but 

 generally in so light a form that throughout the whole time 

 but one inch was registered in the rain-gauge ; during the 

 same time four inches and a half of rain fell at Dorjiling, 

 and three inches and a half at Calcutta. The mean tem- 

 perature was 50° ( i Iax \ 6 5J ; extremes, ~ The mean range 



*■ v Mm. 40 7 y ' 7 38 * o 



(23° 3) was thus much greater than at Dorjiling, where it 

 was only 8° 9. A thermometer, sunk three feet, varied 

 only a few tenths from 57° 6. By twenty-five comparative 

 observations with Calcutta, 1° Fahr. is the equivalent of 

 every 362 feet of ascent ; and twenty comparative observa- 

 tions with Dorjiling give 1° for every 340 feet. The 

 barometer rose and fell at the same hours as at lower 



* This new species has been described for the "Flora Indica" of Dr. Thomson 

 and myself: it is a remarkable plant, very closely resembling, and as it were 

 representing, the D. Brunonianum of the Western Himalaya. The latter plant 

 smells powerfully of muek, but not so disagreeably as this does. 



