610 
Rotation of Crops. 
the effects ot the manuring and treatment of the first crop oi 
the course — the turnips — were manifest in the produce of the 
fourth crop — the wheat ; and also that the effects of fallowing, 
or of growing and removing a highly nitrogenous crop, in the 
third year, was clearly traceable on the crop of the fourth year, 
and to some extent, though in a much less degree, on the subse- 
quent crops commencing the next course. 
The Amounts of Produce Grown in Rotation, and in 
the Various Crops Grown continuously. 
Obviously, when considering what are the benefits arising 
from rotation as distinguished from the growth of the individual 
crops continuously, it is desirable, as far as practicable, to com- 
pare the results of the two methods in regard to their yield per 
acre of some of the more important constituents of the crops. 
For the purposes of such a comparison, it will be of interest to 
illustrate the point by reference specially to the amounts of dry 
matter , nitrogen , total mineral matter (ash), phosphoric acid, and 
potash (and in some cases of lime), in the crops grown in rota- 
tion, and in those grown continuously, under as far as possible 
parallel conditions as to manuring. Accordingly, so far as results 
obtained under rotation are concerned, the amounts of each of 
the above constituents in the average produce per acre per 
annum over the eight courses (second to ninth), under each of 
the twelve different conditions as to manuring, or other treat- 
ment, are adopted ; and these are compared with the amounts 
obtained when the individual crops are grown continuously ; in 
each case when practicable in the same eight seasons as those in 
which the rotation crops were obtained, and under the same, or 
nearly parallel, conditions as to manuring. 
The Amounts of Dry Matter produced in the Rotation, and in 
the Continuous Crops. 
Table V. shows the average annual amount of dry matter 
produced per acre, in each of the four crops — roots, barley, legu- 
minous crop, and wheat — grown in rotation, and continuously, as 
above described. It shows the amounts, separately in the roots, 
leaves, and total produce, of the turnips ; in the grain, straw, and 
total produce, of the barley, and of the wheat ; in the com, straw, 
and total produce, of the beans ; and in the clover. It will be 
seen that the arrangement and headings of the columns are ex- 
actly th6 same as in the Tables of produce already considered ; 
and that, fdr each description of crop, or part of the crop, the 
