EXPERIMENTS ON THE GROWTH OF ROOT-CROPS. 
EXPERIMENTS with TURNIPS were commenced in 1843, 
Hight acres, divided into numerous plots, were set apart 
for the purpose; and the crop was grown for ten consecu- 
tive years on the same land (“Norfolk Whites” 1843- 
1848 and “Swedes” 1849-1852); on some plots without 
manure, and on others with different descriptions of 
manure. Barley was then grown for three consecutive 
seasons (1853-1855) without manure, in order to test the 
comparative corn-growing condition of the different plots, 
and also to equalize their condition, as far as possible, by 
the exhaustion of some of the most active and immediately 
available constituents supplied by the previous manuring. 
A new series of experiments with Swedes was then arranged, 
having regard to the character of the manures previously 
applied on the different plots, and to the results previously 
obtained. This second series was commenced in 1856, and 
is still in progress. 
It is impossible adequately to state the bearing of the 
results in a few words, but the following are some of the 
most characteristic indications :— 
1. Without manure of any kind, the pro 
was reduced in a few years to a few cwts. 5 
the diminutive plants (both root and leaf) cor 
unusually high percentage of nitrogen. 
2. Of “ mineral” constituents, phosphoric 
form of superphosphate of lime) was by 
effective manure; but, when this manure is 
the immediately available nitrogen of the « 
exhausted. 
3. Really large crops of turnips can only 
when the soil supplies a liberal amount 
bonaceous and nitrogenous matter (as well 
constituents) ; and when they are already ave 
the soil, or are supplied in the form of farm: 
rape-cake, Peruvian guano, ammonia-salts, &e. 
of growth, and the amount of the crop, are gree 
by the use of superphosphate of lime appliec 
seed, 
