636 
Rotation of Crops. 
27 lb. That is, although in the case of the rotation wheat 
crops three other crops had been grown since the application of 
the manure, they took up more potash than the continuously 
grown ones for which potash was annually supplied. 
So much for the results relating to the amounts of the two 
important and typical mineral constituents — phosphoric acid 
and potash — taken up by the different crops when grown, respec- 
tively, in rotation and continuously, under different conditions 
as to manuring, and other treatment. Similar results relating 
to other mineral constituents of the crops have been got out, and 
the discussion of some of them brings to view points of consider- 
able interest, but neither time nor space will admit of their con- 
sideration here. It must suffice to refer briefly to the amounts 
of lime taken up by the leguminous crops under different con- 
ditions ; a point which has an interesting relation to the results 
as to the potash taken up by those crops, and to the questions 
which arose in the discussion of them. 
The Amounts of Lime in the Rotation , and in the Continuous 
Leguminous Crops. 
The following Table (X.) gives, for the leguminous crops 
alone, the amounts of lime in the rotation and in the continuous 
crops, in the same form in which the phosphoric acid and potash 
have been given for each of the four crops of the rotation : — 
Very different from what was found to be the case with the 
potash, it is seen that in the rotation bean-crops a very small 
proportion of the total amount of lime is accumulated in the 
corn ; ten, twelve, or more times as much being found in the straw. 
Then, the amounts of lime in the total crops were — without 
manure between 15 and 16 lb. ; with superphosphate, which of 
course supplied some lime, the quantity was raised to 18-68 and 
20 - 71 lb. ; and with the mixed manure, also supplying the same 
amount of lime in its superphosphate, it was further raised to 
26-57 and 27*71 lb. It is further seen, that the continuously 
grown beans contained — in corn, straw, and total produce — in 
some cases only about, and in others not much more than, half 
as much lime as the rotation ones. 
It is remarkable, however, that whilst without manure the 
rotation bean-crops contained only from 15 to 16 lb. of lime, 
the clover contained 67‘8 and 59T lb.; with superphosphate 
the beans gave 18-68 and 20-71 lb., and the clover 158-62 and 
184-52 lb., or about eight times as much as the beans; and 
lastly, with the mixed manure, the bean-crops contained 26 - 57 
