588 
Rotation of Crops. 
United States, however, it is a gramineous crop — maize — which 
largely takes the place of root-crops in Europe. 
The cereals constituting such a very important element of 
human food, it was natural that they should he grown almost 
continuously so long as the land would yield remunerative 
crops. Hence, the history of agriculture, not only in our own 
country, but in others where these crops were of high relative 
value, shows that it very generally came to be the custom to 
grow them for a number of years in succession, and then to 
have recourse to bare fallow ; or, in some cases, to abandon the 
land to the growth of rough and weedy herbage, affording 
scanty food for domestic animals. 
The improvement upon Jhese practices, attainable by 
alternating other crops with the cereals, was very much 
earlier recognised in the case of the leguminous than of the 
root-crops, the introduction of which is of comparatively recent 
date. 
It was, in fact, distinctly recognised by the Romans more 
than 2,000 years ago, that certain leguminous crops were not 
only valuable as food for animals, but that their growth en- 
riched the soil for succeeding crops — in fact, that they were of 
value as restorative crops grown in alternation with the cereals. 
There is, however, very scanty indication that root-crops were 
an element in their alternate cropping. 
As in the agriculture of the ancients, so in that of more 
modern times, especially in our own country, various legumi- 
nous crops were grown in alternation with cereals long before 
roots were so interpolated. 
It was, indeed, not until about, or after, 1730 that Lord 
Townshend, who, as Secretary to George I., had been in Hano- 
ver, and there seen turnips growing as a field crop, on his 
return introduced them on his own estate in Norfolk, and there 
founded the celebrated Norfolk four-course rotation of turnips, 
barley, clover, and wheat. His own land was previously to a 
great extent a marshy or sandy waste, and its value was 
increased enormously under the new system. It was, however, 
not until towards the end of the century that it became gene- 
rally adopted even throughout his own county. In this exten- 
sion Mr. Coke, of Holkham (afterwards Earl of Leicester), was 
largely instrumental, and the practice seems to have next 
extended into Lincolnshire. 
It was thus that The Four-course Rotation , or, in other 
words, the alternation of root-crops and of leguminous crops 
with cereals, became established. Such alternation is, in fact, 
the basis of all the various rotations which are adopted in 
