BULLETIN OF THE BUSSEY INSTITUTION. 593 
water, — with diffusion of hydrate of potash, — under conditions in. 
which neither chloride of potassium nor chloride of sodium was sen- 
sibly decomposed by the lime water. He found, furthermore, that 
sulphate of lime was only one-fourth part as diffusive as hydrate of 
potash. 
Experience alone can decide as to the availability of the potash 
salts for the purpose now in question. It can be said only that the 
laboratory experiments of Graham go to show that as regards the 
subject of diffusibility, chloride of potassium (muriate of potash) is a 
somewhat better material to mix with lime than chloride of sodium 
(common salt); and that sulphate of potash is decidedly better than 
muriate of potash. But since neither common salt itself nor the 
products of its decomposition by lime are of any direct use as plant 
food, while both the Stassfurt salts are powerful manures, it would 
manifestly be better to employ one of the latter in conjunction with 
the lime, even if the diffusibility of the products of the decomposition 
of the potash salts were less than it really is. Since sulphate of potash 
is less readily soluble in water than common salt, it might not be con- 
venient to slake the quicklime with a solution of it; but it is to be 
remembered that the ordinary process of slaking the lime with brine 
is in no wise essential: the decompositions due to diffusion would doubt- 
less occur if the lime were slaked with water and the salt were added 
afterwards. Hence the dry sulphate of potash might be scattered upon 
the slaked lime after the latter had been strewn upon the peat, or the 
sulphate of potash might be dissolved in boiling water, and the hot 
solution thrown upon the layers of powdery slaked lime as they lie 
upon the peat. 
A practical example of the efficiency of the mixture of lime and 
sulphate of potash has been cited by Peters,* who found that such a 
mixture did better than a mixture of lime and wood ashes for decom- 
posing coarse bones. The same chemist f has recommended a mixture 
of Stassfurt salt and lime for composting moor-earth. 
It is an interesting fact to be remembered with regard to the Stass- 
furt salts, that it is not by their direct importation alone that they will 
make available for American farmers the potash of which so many of 
* Hoffmann’s “Jahresbericht der Agrikultur-Chemie,” 1866, 9. 287. 
t Loébe’s “ Landwirthschaftliche Fortschritt,” 2. 29. 
VOL. I. 50 
