kept for some time in large lleservoirs. 31 



covered reservoir on the 19th November, which was all nearly 

 of an equable temperature, I consider the influence of the 

 heating course to have ceased in the first week of February, if 

 not before. The reservoirs have since been pumped dry, and 

 therefore these experiments cannot be repeated, until they 

 are replenished with brine in April or May next. 



It is remarkable that the probe indicated no signs of a 

 lieating influence affecting the water in the large reservoir at 

 Narainpore on the 19th November, though the specific gravity 

 of the brine near the bottom was little less than that of the 

 water in the long reservoir at Balya Ghat on the 5th Novem- 

 ber, its mean spec. grav. being also considerably higher than 

 the mean of the latter. Moreover the heating influence was 

 scarcely traceable in the covered brine reservoir at Narain- 

 pore on the 1 9th November, which perhaps may be accounted 

 for by the large previous expenditure of brine, say about three- 

 Iburths of its original contents, the consumption of which had 

 been replaced to within a foot of the general level by filtration 

 from the ground and leakage at the gate communicating with 

 the adjoining terrace and brine fields; whereas the expendi- 

 ture of brine in the contiguous open round reservoir other- 

 wise similarly situated, was but half of the original contents 

 up to the mi'ddle of January, its entire volume being about 

 170,000 cubic feet, while the covered reservoir contained only 

 about 50,000. In these two reservoirs all the brine when 

 first let in was of a high degree of saturation, ranging from 

 1170 to 1200 sp. gr. and consequently containing little or no 

 sulphate of lime, which ingredient in the composition of sea- 

 water, I have observed at Balya Ghat, is always deposited 

 upon the terraces there, considerably before the brine begins 

 to deposit its sulphate of soda. But this was not the case with 

 respect to the brine in the large reservoir at Narainpore, nor 

 in that of a longer narrow one at Balya Ghat, except perhaps 

 a small proportion of the latter, both of which were chai'ged 

 with brine of only] 070 to 1085 sp.gr., a much higher degree 

 however than that of the contents of the long reservoir in any 

 previous year ; and in both of them the water had remained 

 undisturbed, except by the action of the atmosphere ; yet in 

 one of them a high degree of heat was observed, and in the 

 other, where I should sooner have expected to find it, no in- 

 dication of heat was perceived beyond the probable tempera- 

 ture at which it was filled in June. 



In order to ascertain however whether any fermentation 

 and disengagement of heat takes place on the mixture of 

 saturated brine with brine of a weaker degree, I lately pro- 

 cured from Bulya Ghiit some bottles of brine of different de- 



