58 University Geological Survey of Kansas. 
sium salts are converted into acid carbonates in the small 
intestines according to the equation : | 
MgsSO,+ Na,CO;+ H.O+CO,=MgH,(CO,).+ Na,SO,. 
It is quite immaterial what particular salt be given, as the 
hydrate, chlorid or sulfate are all converted into the carbon- 
ate. However, in the case of the sulfate, the sodium sulfate 
which is formed is, of course, also a cathartic; so the effect is 
doubly large. The hydrate and carbonate, on the other hand, 
possess also the action of alkalies. — 
Manganese is not a very common ingredient in mineral waters, 
or at least it is present in so small a quantity that it is not often 
reported. ‘There are some waters, however, in which it is pres- 
ent in notable quantities, and one or two that are strongly 
impregnated have been recently found in Kansas. In most 
analyses the manganese is considered to be present as bicar- 
bonate or sulfate. As manganese is normally present in the 
blood, it might be supposed to be of considerable value thera- 
peutically, and, indeed, much is claimed for it by some. It 
promotes the flow of bile, and is no doubt useful on account of 
its tonic and reconstructive properties. It is so often associated 
with iron in mineral waters that we have not often an oppor- 
tunity to study its action alone. Recent authorities claim that 
manganese is not absorbed at all into the system, unless given 
in corrosive doses. 
The Potasseum ions seem to have no special therapeutic action, 
as they are so rapidly excreted. Potassium compounds are 
quite similar to those of sodium. As carbonate, it corrects 
acidity and acts as a diuretic in connection with other alkalies. 
Sodium salts are very abundant in waters, on account of 
their great solubility. As sodium and chlorin ions possesss 
very slight toxicity, their combinations are chosen when the 
action of other ions is to be studied. In some waters the car- 
bonate and bicarbonate is very abundant. As sodium carbonate 
is found in the blood, saliva, urine, and other fluids of the body, 
it would be thought to be of importance in substances taken 
into the body. Sodium-carbonate waters have the general prop- 
