1838.] On the spontaneous heating of Brine. 1017 



3 feet. 



3f 



Naminpore. 



>. 1 



11 inches. 



2 



11 



3 



11* 



4 



12 



5 



12* 



6 



13 



7 



14 



8 



15 



9 



15$ 



10 



15$ 



11 



15 



12 



15 



13 



15 



14 



15$ 



15 



16 



16 



15$ 



17 



14 



18 



13$ 



19 



12$ 



20 



13 



20$ feet. 23 feet. 



But great exactness in the specific gravity register during the whole 

 period would have been impossible from the discovery of an error 

 of .009 in the weight of the instrument on the 9th October, whioh 

 quantity it had lost by constant use since the 17th May : the subse- 

 quent observations were corrected accordingly, and care was afterwards 

 taken to compare the hydrometers at short intervals. 



It remains for me to notice, that none of the masses of brine tested 

 by the probe in the present series of observations, were under cover ; 

 that a fetid smell is usually given out by the brine when pumped up 

 after it lias been long in the reservoirs, and that the surface of the wa- 

 ter in the long reservoir, No. 3, at Bally a Ghat was observed in 

 February and March last, (being then in perfect repose and the depth 

 of water being about 2 feet, the remnant of the supply let in before the 

 rains of 1837,) to assume successively the colors of blue, green, brick- 

 dust red and crimson, but returned to the ordinary appearance of water 

 in a month or six weeks after these changes commenced. The surface 

 of the brine in Bally a Ghat reservoir No. 1, the depth of which had 

 been then reduced by Soonies to about five feet, was observed a about 

 a week ago to be of a bluish lead colour which did not shew itself 

 before the soonying commenced, and it gives out a strong fetid smell 

 which also was not perceptible before. 



Calcutta, 28th January, 1839. 



6 m2 



