OLIVER: MINERAL SPRINGS OF THE WEST RIDING. 353 
years ago, in the Chloride of Iron well. 
Undoubtedly local chemical changes contribute towards individ- 
ualizing the various waters. The following reactions have been 
pretty clearly established. 
(a) The reaction between Carbonate of Iron and an Alkaline 
Sulphide as expressed by the formulge : 
Fe CO3 + Nag S = Fe S + Nag CO3. 
Fe CO3 + 2 (Na HS) = Fe S + Nag CO3 + H^S. 
The insoluble but finely divided precipitate proto-sulphide of 
iron, will probably fill in the cracks and fissures of the different 
channels, and, by coating over the shales will further contribute to 
the isolation of currents of saline water containing Carbonate of Iron 
or a sulphide — just as one or the other of these constituents may 
predominate. This re-action suggests the source of the alkaline car- 
bonates present in the Bilton, Starbeck, Harlow -Car, and Beckwith 
issues, which do not contain the Chlorides of Calcium and Magnesium 
(see (c) ). 
(b) The reaction between the soluble salts of Barium a/nd 
Strontium and Sulphates, 
Ba ( CI2 Ba ) (CI2 
vel \ vel +Ca 864= vel y SO^ + Ca -^vel 
Sr ( CO3 Sr ) (CO3 
The precipitated Barium and Strontium Sulphates will gradually 
plug up any cavities or rents in which they are deposited. 
(c) The reaction between Alkaline Carbonates and the Chlorides 
of the Alkaline Earths. 
Alkaline Carbonates cannot co-exist along with the chlorides of 
Calcium and Magnesium : 
Ca) Ca ) 
Nag CO3+ velV CI2-2 Na Q\+ vel [ CO3 
Mg) Mg ) 
Hence in the saline waters of Low Harrogate and the Bogs- 
Field, which contain these chlorides, Alkaline Carbonates are not 
found — being broken up as soon as formed — but they survive in the 
issues of sulphur water immediately outside Harrogate (see (a) ). 
(d) The reaction of Protochloride of Iron with the Carbonates oj 
the Alkaline Eartlis. Carbonate of Iron and the Chlorides of the 
