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" founded on other views ? Your practice may have been 
"generally good, but you have explained its success on 
wrong principles, and the application of these wrong prin- 
" ciples may have led you into error in other cases."* 
Now if this opinion of the learned Professor be true, how 
absurd must be the practice of the farmer in carrying innu- 
merable loads of straw into his fields in the shape of manure! 
How much labour is in vain bestowed in collecting straw and 
stubble with which to compose his dunghills I How ignorant 
the farmers of all ages, who universally have set such great 
value upon straw ; and how trifling the disputation whether 
straw in the shape of short dung or long dung be more ad- 
vantageously employed ! But by applying carbonaceous 
matter to the soil, that we do reap it back in the form of hay, 
corn, or straw, is proved by direct experiments of farmers. 
In those upon the comparative value of manures, for the 
Saxon and Prussian authorities, by Professor Hembsladt, of 
Berlin, and afterwards repeated, with unvaried success, by 
Professor Sch abler, any soil, which yielded without manure 
three times the quantity of seed sown, yielded five times that 
quantity if manured with old herbage, as grass, leaves, 
straw, &c. 
In some valuable experiments by Arthur Young on dif- 
ferent manures. 
Simple soil, without manure, produced 280 Bush, of Potatoes. 
Dung, 32 cubic yards per acre 400 „ 
Barley straw, tons per acre 300 ,, 
Dung, 32 cubic yards, 480 gallons \ 
urine j " 
These experiments alone prove that carbonaceous matter is 
reaped back from the soil. 
But surely the learned Professor, as well as Liebig and 
Dr. Daubeny, have overlooked the existence of humic acid in 
* Durham Advertiser, 12th Feb., 1841. 
D 
