30 Mr. A. B. Northcote on the Brine-springs of Worcestershire. 



waters, that the only bodies existing in quantity sufficient to 

 admit of their amount being determined, were soda, lime and 

 magnesia, chlorine and sulphuric acid ; free carbonic acid was 

 indeed preseut, but it was impossible to take the brine from the 

 pits, and as they issued from the delivery pipes in a state of 

 foam, any attempt at the determination of this gaseous consti- 

 tuent was rendered useless : the existence of other substances 

 was also ascertained, but their amount was so small as effectu- 

 ally to elude detection, unless a considerable quantity of water 

 was operated upon. These waters contain 25 per cent, of solid 

 matter ; the evaporation of a comparatively small bulk of brine 

 therefore yielded a residue which soon became cumbersome ; 

 nearly two gallons of the Droitwich brine, and rather more than 

 one of that obtained at Stoke, were, however, evaporated. The 

 plan of proceeding was to evaporate to a small bulk, and to test 

 portions of the mother-liquor poured off from the deposited 

 salts; first, for bromine and iodine, by evaporation to dry- 

 ness and exhaustion with alcohol, repeating the process until 

 a small saline residue was obtained; this was then examined 

 in the usual manner by mixing thoroughly with starch-paste, 

 and adding a single drop of nitric acid. Secondly and thirdly, 

 for potassa and lithia, by the appropriate and well-known 

 methods : the residue separated from the mother-liquor was 

 exhausted with nitric acid, and the acid liquid examined ; for 

 iron, by converting the nitric into an acetic solution, and test- 

 ing with ferrocyanide of potassium ; for manganese, by Mr. 

 W. Cram's method, the reaction of binoxide of lead ; for phos- 

 phoric acid, by the action of molybdate of ammonia; and for 

 alumina, by igniting the solid produced by evaporating the acid 

 solution with nitrate of cobalt. The residue insoluble in nitric 

 acid was further tested for fluorine and stront a, by first submit- 

 ting it to the process for producing hydrofluosilicic acid, and 

 then examining the insoluble residue resulting from that process 

 for strontia. Nitric acid and ammonia, arsenic, antimony, and 

 tin were tested for in separate portions of each water. 



As these brines closely resemble each other in their largely- 

 occurring constituents, so do they also in the traces of substances 

 which they contain. Careful examination of a portion of the 

 mother-liquor, equivalent to half a gallon of the water, has shown 

 in the case of each the presence of a minute quantity of bromine, 

 but iodine appears to be totally absent : another portion of the 

 mother-liquor, representing about a quart of brine, has in both 

 instances yielded a distinct trace of potassa, whilst no evidence 

 of the presence of lithia has been obtained. In the insoluble 

 residues a distinct trace of iron has been found; manganese, 

 however, aa might have been expected when so small a quantity 



