BULLETIN OF THE BUSSEY INSTITUTION. 365 
land) ; thirty-two experiments with sulphate of potash, of the higher 
grades, gave an increase of 54 kilos. of beets for 1 kilo. of the sul- 
phate ; from twenty-one experiments with wood-ashes, used either 
by themselves or with superphosphate, it appeared that 1 kilo. of the 
ashes had produced an increase of 2.7 kilos. of beets,* while from 
several hundred experiments with superphosphates it appeared that 
1 kilo. of the material gave an increase of 5 kilos. of beets. For 
potatoes he computes, from twenty experiments, that 1 kilo. of 
chloride of potassium produced nearly 34 kilos. increase; and a 
kilo. of sulphate of potash about as much or rather more than the 
chloride. For grain the results were much less favorable. In spite 
of several brilliant exceptions in the case of oats, it appeared that 
the increase of grain on fields manured with Stassfurt salts had 
hardly been equal on the average to the weight of the fertilizer 
employed. 
A grave objection may of course be urged to averages such as 
these, in that they do not give just prominence to results that are 
positively favorable. ‘The figures, as given, actually conceal the 
conspicuous merit which the fertilizer has exhibited in certain 
cases. The question, as presented in this article, is not at all 
whether potassium-salts are useful fertilizers in all cases, — that 
question has long since been answered in the negative. The prob- 
lem now awaiting the verdict of practical experience is, to what 
soils and in what forms had potassic fertilizers best be applied? It 
is hardly necessary to say that there are numerous European ex- 
periments made with Stassfurt salts which show very favorable re- 
sults, or to urge that the use of these fertilizers has been frequently 
commended. The following citation from so competent an ob- 
server as Dr. Voelcker + expresses a conviction which -he arrived 
at after much experience and observation. ‘‘ On reviewing this 
report, it will be found that in every trial in which potash-salts 
(kainit) were applied to root-crops, either alone or in conjunction 
with other fertilizing matters, they materially increased the crops. 
Considering the number of trustworthy experiments now on record, 
all affording distinct evidence of the utility of potash-salts as ma- 
nuring constituents of a turnip, potato, or mangold manure, in- 
tended to be used upon light land, there can be little doubt of the 
* As Mayer remarks (p. 112, note), this result must be regarded as compar- 
atively-speaking high, in view of the relatively small amount of potash ina 
single kilogram of ashes. 
+ ‘‘ Journal of the Royal Agricultural Society,” 1871 (2), 7. 382, 386. 
