BAILEY. | Mineral Waters. 33 
in large quantities from spring water which is allowed to stand 
in an open vessel. 
‘‘5. A difference in temperature may change the composition, 
as substances held in solution at one temperature may not be 
soluble at another temperature.’’ 
GASES IN MINERAL WATERS. 
Oxygen may unite with the constitutents of the water and 
change the composition, as may also carbon dioxid and certain 
sulfur compounds. This is not true, however, of nitrogen, as 
it is so inert that it does not easily unite with the ordinary sub- 
stances present in the water. By the intervention of bacterial 
life, and as in the roots of certain plants like clover and alfalfa, 
the nitrogen of the air is ‘‘fixed’’ so that it can be assimilated, 
so the influence of plants on the composition of cultivated soil 
is too important to be ignored. 
Nitrogen, Argon, and Helium. 
It is an interesting fact that at one time a certain physiolog- 
ical action was attached to mineral waters, and some authorities, 
especially Spanish physicians, introduced a new class of mineral 
waters, namely ‘‘azoades,’’ or nitrogenous waters. It is quite 
probable, however, that what was frequently called nitrogen in 
mineral waters may have been largely helium and argon, as 
these new elements have been discovered in mineral waters 
recently. Dr.C. H. Bouckard” has found helium and in some 
cases argon in the mineral waters of the French slope of the 
Pyrenees. He was led to this investigation by noticing that 
on the Spanish slope of the Pyrenees certain so-called nitroge- 
nous waters had been discovered. Ramsey“ has found argon in 
several mineral springs. Rayleigh” found helium in the pro- 
portion of 1.24 parts per 1000 in some of the Bath springs. It 
is by no means proven, however, that in some cases these gases 
may not have come directly from the air, having been dissolved 
in the rain water. It is not proven that the nitrogen in the 
water had a remedial action, any more than it has been proven 
13. Comptes Rendus, CXXI, p. 392, 
14. Chem. News, vol. 72, p. 95. 
15. Chem. News, vol, 73, p. 247. 
3—Vil 
