880 BULLETIN OF THE BUSSEY INSTITUTION. 
It is to be observed that, although the fertilizers numbered III. and 
IV. contain enough sulphuric acid to enable the dealers to speak of 
them as if their potash were in the form of a sulphate, they cannot 
justly be regarded by the farmer as sulphate of potash, or as possessing 
any quality which would tend to make them preferable to the muriate. 
They consist in reality of mixtures of the chlorides and sulphates of 
sodium, magnesium, and potassium, and are in every respect inferior to | 
the high grade “ muriate,” or chloride of potassium, such as was de- 
scribed under Nos. I. and II. 
The fact that the American market has for several years past been 
flooded with the lower grades of the Stassfurt fertilizers is a curious evil, 
that needs to be generally known, — and to be corrected. ‘The higher 
grades are, of course, much better able to bear the costs of transporta- 
tion, and should by good rights always be brought to us, as has been 
indicated in the note on page 185 of this Bulletin. I am informed, 
however, that the Stassfurt salts are imported for the most part in the 
vessels which are employed for carrying petroleum to Kurope. Many 
of these vessels are old and of little value, and quite unfit for other uses. 
But, in coming back to this country, they bring many empty petroleum 
casks, and the Stassfurt fertilizers have been found to be well adapted 
to serve as ballast to keep such barrel-laden ships steady. ‘The owners 
of the vessels care only for the weight of the fertilizers ; and, since they 
have usually but little command of capital, they naturally prefer to take 
those classes of salts which will give them the largest amount of dead 
_ weight at the least cost. 
_V. A sample of dark gray “ prussiate residue,” from prussiate of 
potash works at New Bedford, Mass., obtained from W. H. Chessman, 
of Boston, dealer in potashes. ‘This substance was readily and com- 
pletely soluble in water. It contained, among other things, — 
Moisture. . . . » 9. . «4 6 «=. 6 DATS 
Silivie-asid 41 Sue AEK, 8, 2 ee 
Sulphurig acidity. ».i% (splashes 16 babes eee 
Phoaphorie acids is en 05° 4)c9 a) eieistatan keke 
mea. potash (Ko) Se tate) sue Led ce ce, eee 
Beside the constituents enumerated above, the sample contained car- 
bonic acid, traces of iron and alumina, a good deal of sodium, and a 
small proportion of an alkaline sulphide. A small quantity of sul- 
phuretted hydrogen was evolved on adding an acid to the substance or 
Ee 
