STEANGWAYS: HAEKOGATE WELLS. 
327 
except the Pure Chatybeate. 
The Oxygen and Carbonic Acid are also probably in a state of 
combination principally with Lime and Magnesia, while the Nitrogen 
and Carburetted Hydrogen appear to be in entirely a free state. Of 
those gases in a free state the Strong Sulphur Water gives by far the 
largest result ; for if we turn to Professor Hoffmann's analysis we 
find that the gas rising from the surface of the Hospital Strong 
Sulphur Spring contains no less than 99-91 per cent, of Nitrogen 
with a very small per centage of Carbonic Acid ; and if we examine 
all the stronger sulphur wells we shall find that the percentage of 
this gas in a free state is always very large : of the other gases in 
a free state the Carburetted Hydrogen appears to be the one which 
is most abundant, the Old Sulphur Well containing, according to 
Hoffmann, as much as 40 per cent, of this gas. Of the gases which 
are dissolved in the water itself, and which are only expelled by 
ebulition in vacuo are Carbonic Acid with smaller proportions of 
Carburetted and Sulphuretted Hydrogen. 
And lastly the most important of the gases which are in chemi- 
cal combination with various bases are Sulphuretted Hydrogen, 
Chlorine, and Carbonic Acid, which latter may be taken as including 
the greater part of the oxygen mentioned above. The non-gaseous 
constituents of the water are chiefly salts of Soda, Lime, Magnesia, 
and Potash. 
Professor Hoffmann in his analyses of these waters has divided 
them into four principal groups : 
Class I.— The Strong Sulphur Water. 
Class II.— The Mild Sulphur Water. 
Class III. — The Saline Chalybeates. 
Class IV. — The Pure Chalybeates. 
and this seems to me to be the best mode of classing them with 
reference to their sources. 
The principal springs of the Strong Sulphur Water are the old 
Sulphur Well, one of the Wells in the Montpellier Gardens, and the 
Hospital Strong Sulphur Well. These are all characterized by the 
large amount of Chloride and Sulphide of Sodium they contain, as 
well as by the great bulk of their gaseous constituents, especially 
