Mr. A. B. Northcote on the Brine'Springs of Worcestershire. 31 



of iron was present, was not to be recognized. Unmistakeable 

 evidence of the presence of phosphoric acid was obtained in both 

 waters, upon the addition of a small quantity of the nitric acid 

 solution to a quite colourless and nearly dry mixture of nitric acid 

 and molybdate of ammonia. The search for fluorine and strontia 

 has been unsuccessful ; nor have any traces of nitric acid or am- 

 monia, antimony, arsenic, or tin been discovered ; but on passing 

 sulphuretted hydrogen through portions of the brines acidified 

 with hydrochloric acid, a slight but decided brownish tinge was 

 observed in both cases, such as is produced by the same reagent 



-dth of its weight of lead : 



in a solution containing about 

 this I would suggest might be due to the presence of a minute 

 trace of chloride of silver dissolved in the chloride of sodium, 

 since that metal has been found in rock-salt in small quantities* ; 

 so exceedingly trifling is its amount, however, that my attempts 

 to isolate it have been fruitless. The following are the prelimi- 

 nary observations made upon the waters, and the direct results 

 of their analysis : — 



Droitwich brine. 

 January 1854. August 1854. 

 Specific gravity 1-1*893 1-1792 



76°5 F. 

 54°-5 F. 



Temp, of air 

 Temp, of brine 

 Reaction 



Stoke brine. 

 August 1854. 

 1-2044 

 75° F. 

 55° F. 



slightly alkaline, slightly alkaline. 



Table of direct results of analysis calculated to 100 parts. 



* Annates de Chimieet de Physi<iue, '6 sc'r. vol. xxviii. p. 129. 



