OLIVER: MINERAL SPRINGS OF THE WEST RIDING. 345 
Salt, the Sulphide, the soluble compounds of Barium and Strontium, 
and the Proto-chloride of iron. I will pass in review some of the 
principal theories that may be broached to account for the presence 
of these various salts. 
1. — Chlorides. 
The Harrogate waters (the issues of the Bogs-Field and Low 
Harrogate) in at least one leading feature of their chemical constitu- 
tion differ from the others : they contain a very much larger 
proportion of chlorides — in fact, the "best examples of this group of 
springs are strong salt waters, as well as being sulphuretted. For 
example, the Old Sulphur Well, and the Strong Montpellier Sulphur 
contain at least four times as much salt as is present in the Aldfield 
source, though this is more freely charg-ed with chlorides than the 
water of the other issues outside Harrogate.* One issue only (the 
Old Sulphur Spring) throws up annually over six tons of salt, and the 
aggregate output of all the wells cannot be less than from 80 to 100 
tons — an amount which is probably exceeded. This fact provides a 
general notion of the large amount of saline material constantly in 
process of removal from the formations through which the mineral 
water circulates before it discharges itself from the limited area 
comprised by the Bogs-Field and Low Harrogate. Whence is it 
derived ? 
(1) Direct communication with sea water. — You will be aware 
that Sir Charles Lyellf and some other eminent geologists, enter- 
tained the theory of the direct passage of sea water through the 
porous and fissured bed of the ocean, and along subterranean conduits 
formed by faults and rents of the rocks to the issues of saline water, 
even though situate many miles inland. Two principal difficulties 
present themselves in applying this hypothesis to the Harrogate 
salines — one phj^sical and the other chemical ; namely, altitude (can 
the water of the ocean rise above the sea level ?), and the presence 
of an average ratio of 10 per cent, of soluble sulphates in the saline 
residue of sea water. So that should it even be conceived possible 
* I am indebted to Mr. R. Hayton Davis, F.C.S., for skeleton analysis of 
the various waters. 
t See Principles of Geology, 6th Ed. Vol. 1., pp. 396, 397. 
