452 Transactions.—Chem istry. 
ammonia, showing very clearly that these saline solutions are more powerful 
solvents in this respect when used cold. 
The exact quantity of calcic carbonate which a solution of any one of 
these salts of a certain strength can dissolve has not yet been ascertained, 
but the results of experiment No. 3 show a certain minimum capacity of 
sodic chloride in this respect. Thus it appeared by it that the highly 
calcareous Oamaru water, when charged with sodic chloride at the rate of 
one pound per gallon, does not afford any calcareous precipitate when sub- 
mitted to Clarke’s process. Now the total quantity of calcareous precipitate 
afforded me by this process as applied to the water in its normal state was 
no less than 21-75 grains to the gallon. Clearly then this quantity of 
calcareous matter (calcic carbonate) is retained by this water in a soluble 
form, showing a certain minimum capacity of the sodic chloride in this 
respect, a computation which may, however, be found to fall far short of 
that which represents its actual capacity when this shall be properly tested. 
In conelusion, I would submit to you that these results show :— 
Ist. That Clarke’s softening process cannot be advantageously applied 
to hard water containing alkaline salts in quantity unusually large for such 
waters. 
2nd. That sea-water, containing as it does a very large quantity of these 
salts, has a considerable solvent power upon every limestone formation with 
which it is in contact; a fact which should, I conceive, be taken into account 
by geologists in connection with the erosion of these rocks by sea-water. 
9rd. That the actual quantity of caleie carbonate present in one gallon 
of average sea-water may be considerably more than that which is now 
customarily assigned to it—viz., three grains to the gallon, as this quantity 
is merely got by a computation in which the solvency of the compound in 
pure water is taken as a guide; it is obvious, however, that an addition 
should be made to this, so that the quantity dissolved by the salts of 
this water may be included in the estimate. 
Art. LXVIII.—On the Degree of Solubility of certain Earthy Carbonates in 
pure Water. By W. Sev, Analyst to the Geological Survey Depart- 
ment. 
[Read before the Wellington Philosophical Society, 12th January, 1878.] 
Tue degree to which certain earthy carbonates are held to be soluble in 
pure water by those chemists who have studied this matter, is so variously 
aud so divergently stated by them that, practically, we cannot rightly 
