112 



Selections. 



[No. 1, NEW SERIES. 



proceeding in the south-easterly direction, a specimen was chosen 

 from the active department of Winsford, in the central district, 

 and Messrs. Ray and Son furnished me with the brine which they 

 employed ; whilst in the extreme south-east, Mr. Blackwell pro- 

 vided me with samples from the spring which supplies his exten- 

 sive works at Wheelock. 



The depth at which the brine is found, and the level to which 

 it rises, vary very much at different places. It appears that it is 

 generally necessary to sink from thirty to fifty yards, in some cases 

 even to a depth of eighty yards, before the spring is arrived at ; 

 the water then rises in the shaft to within from twenty to ten yards 

 of the top, sometimes even to the surface. The general level of 

 the brine in the pits is, however, far below this standard, as its 

 removal by the pumps is so rapid as never to allow it to rise to its 

 full height. 



As in the case of Worcestershire brines, I was desirous of ascer- 

 taining whether the composition of these springs varied with the 

 different seasons of the year, with this view analyses were made 

 in every instance of separate specimens taken respectively in Janu- 

 ary and August, and, as I had already found in the case alluded to, 

 no difference Worthy of note existed between them. 



The analytical methods which have been adopted in the exami- 

 nation of these brines, are precisely those described in the former 

 memoir on the Worcestershire springs ; instead, however, of eva- 

 porating small portions of the waters to obtain mother-liquors and 

 residues which might contain the rarer constituents, I obtained 

 portions of the liquid which remains in the pans after the removal 

 of the salt, and of the solid cake of earthy matter which adheres 

 so tenaciously to the bottom of the pan as to require separation 

 by the pick, and is called by the workmen " pan-scale." The 

 former of these was tested for potassium, bromine, iodine, and 

 phosphoric acid ; and the latter for arsenic, antimony, tin, iron, 

 manganese, aluminum, strontium, and fluorine. - The brine itself 

 was also examined for silica, for organic matter and its resultants, 

 ammonia and nitric acid, and the metals precipitable by hydro- 

 sulphuric acid. The principal constituents of these waters are 



