BULLETIN OF THE BUSSEY INSTITUTION. 363 
by the use of the Stassfurt potash-salts have been extremely vari- 
able and uncertain. Indeed, it has been asserted by several writ- 
ers that it is only on sour mowing-ficlds and on moors that have 
been reclaimed by the method of covering with gravel that the 
Stassfurt salts have approved themselves really profitable. Under 
the ordinary conditions of farming-practice the use of them is said 
not to have brought remunerative returns in the majority of cases, 
while in some instances they have been found to be actually hurt- 
ful. Mayer has expressed himself somewhat as follows: It may 
be admitted, he says, as a fact that is generally known, that the 
Stassfurt salts — the cheapest form of potassic fertilizers, and the 
kind which has been most commonly applied hitherto — have failed 
to yield results that were commensurate with the expectations, 
even when they were applied to soils which from the mode of crop- 
ping or from the results of chemical analysis were supposed to be 
relatively poor in potash. He urges that the question is how to 
explain this fact. I have myself urged, in another connection,* 
that one conspicuous reason why potash compounds are held in so 
little esteem by most European farmers will be found in the time- 
honored practice which prevails there of returning large quantities 
of straw to the land, and in that way supplying in abundance the 
potash which is contained in the straw. While upholding in gen- 
eral the superiority of wood-ashes, or of composts made of pot- 
ashes, on account of their power to supply nitrogenous as well as 
potassic food, I have dwelt also on some of the good results that 
were obtained in this country long ago from the use of potash-com- 
pounds other than the carbonate as it exists in wood-ashes. Pro- 
fessor Atwater + likewise has cited numerous instances where muri- 
ate of potash has done good service even when used by itself. On 
some poor soils where neither nitrate of soda nor superphosphate 
of lime, whether used separately or together, brought crops of po- 
tatoes or Indian corn, the muriate of potash did excellent service 
—every plot that had been dressed with this substance having 
given a large yield, while no crops, or as good as none, were ob- 
tained from the competing plots that had not received any of the 
potash-salt. He remarks that the benefit derivable from the mu- 
riate was apt to be striking whenever there was any benefit at all. 
In some of his cases it appeared that the potash-salt, when used 
* «Bulletin of the Bussey Institution,” 1874, 1. 160. 
+t ‘‘ Report of Work of the Agricultural Experiment-Station at Middletown, 
Conn.,” 1877-78, p. 82 et seg. 
