644 Meteorological Register at Barelly ', in 1831 . [Dec. 



year, 15 observations gave the altitude, feet 6777.7, and another set of 

 10 made it, feet 6775.1, and then the latter were taken after a long 

 march in the hills, during which the barometer had been repeatedly 

 refilled. I have a barometer made by Bate, on the principle of 

 Guy Sussac's syphon barometer, with Captain Kater's improvements, 

 (that is the description given of it,) and it seems in excellent order. 

 This stands about .05 higher than a barometer of the above simple 

 make, and filled in the same easy manner as above mentioned. (I should 

 mention that the tubes used have all been of large bore.) But I have 

 no means of discovering the error of either. 



The following observations were made at Hardwar, near the centre 

 of the pass, in a house about 150 feet above the bed of the Ganges : 

 Bar. 32°. Ther. 



84 at 10 P. M. suddenly came a cool 



96 breeze and reduced the Ther. to 91. 



100 



106 



104 



99 



98 



75 



83 



94 



102 



106 



The height deduced from comparison with corresponding altitudes in 

 Calcutta is, from those in the Journal*, 1214 feet above Calcutta, and 

 from those at the Surveyor General's Office, 1276 do. 



The latter are more numerous. The mean of these would be about 

 1245 feet, and if the estimated altitude above the river be deducted, 

 it would leave the height of the Ganges at Hardwar above Calcutta 

 about 1095 feet. The barometer used was, as before, a plain tube, 

 freshly filled with mercury. Though not tried, I suppose the depression 

 of the moist bulb thermometer must have been near 3 0. 



In elucidation of the remarks on filling barometers when the air is 

 damp, (vide Journal of the As. Soc. ii. 260.) I may record the following- 

 experiments made by myself : 



On the 12th July last, when the depression of the moist bulb ther- 

 mometer was 9|°, I filled a tube which stood exactly the same as one 

 filled on the 3rd June, when the air was very dry ; in both these tubes 



* My barometer stands on an average .044 lower than the Surveyor General's, 

 which will make an addition of 50 feet necessary to the altitude calculated.— Ed. 



1833, May 



24, 



11 A. M. 



28.216 







9 20 A. M 



. .236 







Noon . . 



.224 







2 P. M. 



.182 







4 P. M. 



.103 







Sunset . . 



.107 







9f P. M. 



.119 



it 



25, 



Sunrise. . 



.153 







7 A. M. 



.220 







9 A. M. 



.227 







Noon . . 



.219 







2 P. M. 



.187 



