JOURNAL 
OF THE 
ROYAL AGHICULTURAL SOCIETY 
OF ENGLAND. 
XV. — On the Continuous Growth of Wheat on the Experimental 
Plots at Rothamsted during the 20 Years, 1864 to 1883, in- 
clusive. By Sir J. Benxet Lawes, Bart, LL.D., F.R.S., and 
J. H. Gilbert, LL.D., Ph.D., F.R.S. 
In the Journal of the Royal Agricultural Society of 1864 we 
published an article on the growth of wheat for 20 years in 
succession — 1844 to 1863 inclusive — upon the same land. We 
have now to record the continuation of these experiments over 
a similar period of 20 years — 1864 to 1883. 
The 20th crop of the first period — grown in 1863 — was 
much the largest of the whole ; and, as will be seen further on, 
the first crop of the second period of 20 years, grown in 1864, 
was also the largest of the whole ; further, these two crops of 
1863 and 1864 were larger than any two crops grown during 
any of the other 38 years. 
The first period comprised a number of seasons of great 
abundance : the second period a number of seasons of very 
deficient yield. 
In the first period an artificial manure applied continuously 
to the same plot of land, produced for 10 years in succession 
a crop of 40i bushels per acre : in the second period the same 
plot of land, receiving exactly the same manure every year, 
only produced 30J bushels, an annual reduction of 10 bushels 
per acre for 10 years in succession ! 
Formerly, when the yield was bad, the farmer obtained com- 
pensation in the shape of higher prices for his produce, but in 
this case the larger crops of the first period were sold at con- 
siderably higher prices than the smaller crops of the second 
period. In the first period there was considerable agricultural 
VOL. XX. — S. S. 2d 
