Iiifluence of Climate on Cultivation. 
four-course shift, in which the turnip follows the wheat, is almost 
invariably adopted. The clover-stubbles are dressed with farm- 
vard manure. A considerable amount of slowly decomposing 
vegetable matter vields up a considerable amount of nitrogen 
to the turnip. On the weaker soils this is, perhaps, as much as 
their deficient physical properties will enable the plants to work 
up or assimilate. The Swede, on the chalky and gravelly 
soils of England, is restricted in its growth in a manner similar 
to that of the parsnip at Tel tow. No amount of any kind of 
manures enables the soil to produce maximum crops when such 
radical defects exist. Ammoniacal manures are not attended 
with the same results as when the plants can attain to their full 
growth. 
Over the wolds and downs of the south of England, where the 
physical properties of the soil are so deficient, phosphate of lime 
is in many instances sufficient, or nearly so, to raise such maxi- 
mum crops of Swedes as these thin and hungry soils are capable 
of growing. The addition of large quantities of nitrogenous 
manures is attended with the same waste as in giving an animal 
larger quantities of rich food than it can digest. On the other 
hand, even in the south, where the soil is of deeper staple and 
more retentive in its character, it is, comparatively speaking, 
grateful for nitrogenous manures when applied to the turnip crop. 
The economical application of these substances is dependent 
upon the plants having those conditions of soil which maintain 
them in health, so that thev can assimilate, like the mangold, an 
abundant supply when placed within their reach. 
As is well known, thin and weak soils are better fitted for 
maintaining the growth of the Swede in the moist climate on. the 
west coast than in the drier climate of the east. There the 
lower temperature and less-exhausting character of the droughts 
maintain the plant in vigorous growth through the summer 
months. These conditions admit of large crops being obtained, 
but only by the liberal application of manures having a con- 
siderable quantity of nitrogen in their composition. 
It ought to be borne in mind, too, that with turnips, as witli 
cereals, the advantage of having the nitrogenous element coe:- 
bined in the vegetable form is all the more essential as the 
climate becomes drier. As formerly observed, this form of 
manure seems to have the effect of acting as a diluent of nitrogen, 
probably by its hygroscopic properties in attracting moisture from 
the atmosphere. On weak soils, therefore, physical deficiencies are 
so far compensated by vegetable manurinsr. A larje amount of 
soluble lood in a soil can only be economically taken up and 
turned into vegetable structure when the plants have a full 
supply of moisture. Irrigation allows Italian rye-grass to 
