440 



HUMIDITY AT VARIOUS ELEVATIONS. Appendix G 



feet, arises from most of the observations having been made on the outer 

 range, where the atmosphere is surcharged. The majority of those at 

 10,000 to 12,000 feet, which also give a disproportionate amount of 

 humidity, were registered at the Zemu and Thlonok rivers, where the 

 narrowness of the valleys, the proximity of great snowy peaks, and 

 the rank luxuriance of the vegetation, all favour a humid atmosphere. 

 I would have added the relative rain-fall to the above, but this is so 

 very local a phenomenon, and my observations were so repeatedly 

 deranged by having to camp in forests, and by local obstacles of all 

 kinds, that I have suppressed them; their general results I have 

 given in Appendix F. 



I here add a few observations, taken on the plains at the foot of the 

 Sikkim Himalaya during the spring months. 



Comparison between Temperature and Humidity of the SikJbim Terai 

 and Calcutta, in March and April, 1849. 



No. 



of 



Obs. 



4 

 4 

 3 

 3 

 4 

 3 

 2 

 8 



31 



Locality. 



Elev. 



above 



sea, 



Feet. 



TEMP. 



r>. p. 



TENSION. 



SAT. 



C 



82-2 

 928 

 84-2 

 90-1 

 84-9 

 87-4 

 80-2 

 85-5 



85-9 

 89-7 



T. 



70-6 

 85-5 

 75-0 

 81-2 

 77 1 

 74-9 

 68-0 

 80-0 



C. 



61-7 

 62-6 

 68-7 

 541 

 61-3 

 64-7 

 66-2 

 55-4 



61-8 

 76-7 



T. 



c. 



•553 

 •570 

 •695 

 •429 

 •547 

 •611 

 •642 

 •448 



•562 

 •904 



T. 



c. 



•517 

 •382 

 •605 

 313 

 •466 

 •480 

 •635 

 •376 



•472 

 665 



T. 



Ruminai . 

 Belakoba 

 Rangamally . 

 Bhojepore 

 Tliakyaguuj . 

 Bhatgoug . 

 Saliibgunj 

 Titalya . . 



293 



368 

 275 

 404 

 284 

 225 

 231 

 362 



605 

 63-0 

 62-5 

 44-3 

 60-8 

 54-6 

 53-1 

 56-1 



•532 



•578 

 •568 

 •308 

 •537 

 •436 

 •414 

 •459 



•717 



•485 

 •665 

 •295 

 •588 

 •512 

 •409 

 •459 



•516 

 K-793 



Means . . 

 May, 1850 ) 

 Kishengunj ( 



305 

 131 



790 

 K 78-6 



56-9 

 K71-4 



•479 

 K-759 



Vapour in a cubic foot— Kishengunj 8*20 Terai . 5-08 



... ..„ , Calcutta . 9-52 Calcutta. 5-90 



Mean difference of temperature between Terai and Calcutta, from 



31 observations in March, as above, excluding minima . . . Terai— 69 

 Mean difference from 26 observations in March,, including minima '. „ —97 

 Mean difference of temperature at Siligoree on May 1, 1850 —109 

 »' » Kishengunj „ —111 



From the above, it appears that during the spring months, and 

 before the rains commence, the belt of sandy and grassy land along 

 the Himalaya, though only 3| degrees north of Calcutta, is at least 

 6° or 7° colder, and always more humid relatively, though there is 

 absolutely less moisture suspended in the air. After the rains com- 

 mence, I believe that this is in a great measure inverted, the plains 



