Mr. Horner on the Brine Springs at Droitwich. 101 



Four cubic inches of brine were evaporated to dryness very slowly, 

 in a heat which was not suffered to rise above 212°, and towards the' 

 close of the evaporation it was kept between 170° and 180'. The 

 residuum was reduced to powder, and again kept for an hour in a 

 heat of about 180". The different brines yielded the following 

 quantities of entire salt. 



Walker's pit, 

 Walwyn's pit, 

 Romney's pit, 

 Stuckej's pit, 

 Farle_y's pit, 



317.14 grs. -zz. 2289.75 grs. in a pint. 

 313.40 — =: 2262.75 

 311.00 — -=: 224:5 A2 

 283.50 — = 2046.87 

 2C6.34 — = 1922.97 



This variation in the strength of the different brines is probably 

 owing to the mixture of the fresh-water springs in different propor- 

 tions. Farley's pit, which is the weakest, is perhaps so on account of 

 the brine not being agitated by pumping, whereby the lighter fresh 

 water will only mix with the brine in the upper part of the pit : the 

 bottle of it which I obtained was from near the surface. 



But a solution of this specific gravity he states to contain ^ of its weight of salt; 

 •whereas I have found (B. a.) that three ounces of the brine of Walker's pit, weighing 

 16284 grs. yielded only 431,86 grs. of salt, which is not equal to two-sevenths of the 

 weight. 



The diflference between the results which I have obtained, and Dr. Watson's tables, 

 (if it is not owing to error on my part,) may probably arise from the degree of purity 

 of the salt which he used, and also from the state of it with regard to dryness, before 

 it was added to the water. 



Dr. Holland, in his Agricultural Report of Cheshire, states, that salt, after as much 

 water as possible has been previously drained from it, loses about one-seventh of its 

 weight, when heated and dried before the fire, without being allowed to decrepitate. 



