604 
Rotation of Crops. 
Before passing from the results in Table III. it may be 
observed that, both with mineral manure alone, and with 
mineral and nitrogenous manure together, there is rather more 
produce, both of the clover and of the bean crop, where the 
roots had been fed upon the land, than where they had been 
carted off ; that is the higher the condition of the land. Thus, 
then, the effects of the treatment of the first crop of the course 
— the roots — on the produce of the third or leguminous crop are 
clearly shown. 
As already referred to, in the second and subsequent courses, 
when the third year came round each plot was divided, clover 
or beans being grown on one half, and the other half left fallow. 
We have, therefore, the means of comparing the effects on the 
other crops of the rotation — of fallow on the one hand, which 
of course removes nothing (though there may be the more loss 
by drainage), and of growing beans or clover on the other, a 
characteristic of which is the assimilation, and consequently 
the removal in the crops, especially of large amounts of nitrogen, 
but of other constituents also ; at the same time, however, 
leaving in the land more or less of nitrogenous crop-residue. 
Such a comparison obviously has a special interest, since it is 
chiefly as a substitute for fallow that the growth of leguminous 
crops has been introduced into our rotations. 
The Wheat Crops. 
Table IV. records the results obtained with the fourth element 
of the rotation — the wheat — exactly in the same form as in the 
case of the other crops. 
Looking first to the figures relating to the individual years, 
it is seen that, under each condition of manuring or other 
treatment, there is an enormous variation in the amount of 
produce in the different years, according to the seasons. Thus, 
taking for illustration the results in the first column under each 
of the three main conditions as to manuring, that is where the 
roots were carted from the land, and where in the third year 
of the course it was left fallow, there was, without manure, only 
10$ bushels of wheat in 1879, but 45 bushels in 1863 ; on the 
superphosphate plot there was in 1879 only 14f bushels, and 
46 bushels in 1863; and on the mixed manure plot only 12$ 
bushels in 1879, but 52$ bushels in 1863. Or, comparing the 
quantities of total produce, corn and straw together, which more 
directly represent the amounts of growth, we have, on the same 
plots, without manure, 2,162 lb. per acre in 1879, and 7,446 lb. 
in 1863; on the superphosphate plot 2,905 lb. in 1879, and 
