230 Report of Experiments with different Manures 
results ; but it will, upon the whole, be more convenient to com- 
plete the subject of the quantity of produce before commencing 
upon that of quality. 
Having, therefore, in Part I., considered the acreage amounts of 
the yross produce, or hay, attention will be directed in the present 
section (Part II.) to the acreage quantities of certain constituents, 
or classes of constituents, obtained by the different manures. 
Part III. will be devoted to the discussion of one element of 
quality, namely, that of the description and proportion of the 
different plants developed. 
Lastly, in Part IV., the per-centage composition of the complex 
produce — hay, will be considered. 
The particulars relating to the amount of the several con- 
stituents, per acre, contained in the produce by the different 
manures, are given in a series of Tables, as follow : — 
In Table III.^ — The produce of hay, per acre, calculated in lbs., 
as the basis of the succeeding Tables. 
In Table IV. — The produce of total dry substance, per acre, 
in lbs. 
In Table V. — The mineral matter (ash), per acre, in lbs. 
In Table VI. — The nitroyen in the total produce, per acre, in lbs. 
In Table VII. — The nitroyen in the increase by mamire, per 
acre, in lbs. 
" In Table VIII. — The proportion of the nitroyen recovered in 
increase, for IQO parts supplied in vianure. 
1. The Dry Matter per Acre. 
On the amounts of dry matter, per acre (Table IV.), a very few 
observations will suffice. Taking the average of the three years 
over which the experiments extended, the annual yield of dry 
matter was, loithout manure, almost exactly a ton per acre. This 
is slightly under the amount obtained, without manure, in icheat 
(corn and straw together), taking the average of fourteen years of 
the consecutive growth on the same land ; and it is several 
hundredweights below that obtained in barley, without manure, 
taking the average of six years' consecutive growth on the same 
land. 
By means of manures, the yield of dry matter, per acre, in the 
hay crop, was in several of the experiments considerably more than 
doublcHl. The increased j)roduce of dry matter was thus great — 
indeed the greatest — where no carbonaceous manure whatever was 
emjjloyed. It may be reckoned that the dry substance of the hay 
would contain about 40 per cent, of carbon. Adopting this 
estimate, there would be about 1)00 lbs. of carbon assimilated per 
acre, 
