A 
THE EFFECTIVE USE OF LAND AS SHOWN BY YIELD iu 
readoption of methods and practices employed in the times of the 
Romans. 
As a result of the inclosures an opportunity was made available 
for certain changes in English agricultural practice. The seed for 
these changes was sown early in the eighteenth century by Jethro 
Tull, the apostle of cultivation. The teaching of Arthur Young 
and others in the latter decades of the century and the spread of 
the inclosures hastened an increasing adoption of the methods that 
brought about a great increase of crop yields in England. The in- 
troduction of root crops and clovers from Flanders, the development 
of crop rotations, the increase in number of livestock, and the in- 
creasing and more efficient use of animal manures were the contribut- 
ing factors in the increased productivity of the cultivated area. Con- 
sequently, by 1815, possibly even earlier, average wheat yields in 
England had risen to 20 bushels per acre. 
The economic justification of the adoption of these improved 
methods of production and the resulting costs was the constantly 
rising prices of agricultural products. 
The period from 1780 to 1813 was one of exceptional activity in agricultural 
progress. Apart from the flowing tide of enthusiasm, landlords and farmers 
were spurred to fresh exertions and a great outlay of capital and labor by 
the large returns on their expenditure. All over the country new facilities 
of transport and communication began to bring markets to the gates of the 
farmers; new tracts of land were reclaimed; open arable farms and pasture 
commons were broken up, inclosed, and brought into more profitable cultiva- 
tion; vast sums of money were spent on buildings and improvement. In 
spite of increased production prices rose higher and higher, and carried rents 
with them (9, p. 210). 
The extended depression that followed the Napoleonic wars, how- 
ever, kept agricultural improvement at a virtual standstill up to 
about 1840. 
Livestock was reduced to a minimum; lime kilns ceased to burn; less 
manure was used on the land; the least possible amount of labor was em- 
ployed (9, p. 323). ; 
On the continent, in Germany, wheat yields rose from 10 bushels 
per acre in the closing years of the eighteenth century to about 16 
bushels by the middle of the nineteenth century (7, p. 17). 
During the same period a like change took place in France, with 
wheat yields increasing from an average of about 12 bushels per 
acre during the decade following the Napoleonic wars to about 16 
bushels per acre by the middle of the century (3, pp. 228-233). 
The transition to the modern era of intensive development of 
European agriculture occurred shortly after the publication of the 
work of Liebig. At that time England had just emerged from the 
long economic depression that had set in at the end of the Napo- 
jeonic wars. With a steadily growing demand for food products 
resulting from a rapidly increasing urban population in England 
a widespread and increasing general use of improved agricultural 
methods began to take place. According to Prothero, “ The new 
alliance of science with practice bore rich and immediate fruit.” 
In England crop yields began to rise once more, and by the late 
eighties wheat.yields had risen to a fraction of a bushel less than 
30 bushels per acre (9, p. 361), 
