ON MANURES. 198 



We have already stated our opinion so clearly on the subject 

 of fermentation, in our view of putrescent manures, that it may 

 be thought hardly necessary to add any thing to the discussion 

 of the point in dispute; yet as many farmers have been in- 

 fluenced by the reasoning of chemists, who possess no practical 

 knowledge of agriculture, in favour of the invariable applica- 

 tion of long dung — though opposed by experience — and as it 

 is extremely important that the question should be set at rest, 

 we request serious attention to the following extracts from an 

 able article which has appeared in the Quarterly Journal of 

 Agriculture since the publication of what we had written.* 



It was promulgated as the opinion of Sir Humphry Davy, 

 in 1809, and it has till lately obtained the confidence of most 

 chemists, that ^As soon as dung begins to decompose, it 

 throws off its volatile parts, which are the most valuable and 

 most efficient. Dung which has fermented, so as to become 

 a mere soft cohesive mass, has generally lost from one-third 

 to one one-half of its most useful constituent elements; and 

 that it may exert its full action upon the plant, and lose none 

 of its nutritive powers, it should evidently be applied much 

 sooner, and long before decomposition has arrived at its 

 ultimate result.^ Experience has nevertheless, acted in direct 

 opposition to this opinion. Manure has been continually ap- 

 plied in 'a soft cohesive mass,' and it has continued to raise 

 large crops ; whereas, had it been applied ' long before decom- 

 position had arrived at its ultimate result,' that result would 

 probably have been a loss of crop, manure, and labour. 



'It is certainly an erroneous assumption to say the first 

 stage of fermentation in dung must necessarily throw off its 

 most valuable parts. Every dunghill of fresh dung throws off 



of the Committee of the Doncaster Agricultural Association upon bone ma- 

 nure — 'The general mode of managing fold manure is erroneous, both as to 

 the expense incurred and loss from evaporation. To prevent both, upon 

 carrying it out to the field, it should be forked up to a considerable height, 

 and the whole covered with the soil nearest to the heap; a long heap, like 

 a potato heap, is therefore best; as it accumulates, taking care always to 

 cover the whole of the day's loading, excepting the end to which the next 

 day's work is to be added. The confinement of the steam, which is always 

 observed upon a fresh-made heap of manure, effectually secures the de- 

 composition of the whole; which will cut out like a jelly, without tke usual 

 process of turnim^ over and over.' 



* No. xxiii. pp. 617 to 624. The discoveries alluded to relate to a substance 

 which chemists call Humin, which is said to exist in all soils, and to be formed 

 of carbon and hydrogen. The Htimic acid is composed of humin and oxygen, 

 and its properties enable it tocombine with lime, potass, ammonia, and many 

 BUbstances found in soils and manures, and renders them easy to be dissolved 

 in water, which could not be done in their seoarate state. 



