Nature and preparation of manure. 41 



6red, it has been found to yield a good crop of wheat or rye, 

 nearly double the amount which might be expected from the 

 field without the gypsum. 



But when the farmer by good husbandry, has once put his 

 farm in a condition to produce good crops, it would be better 

 economy to turn his attention to the business of saving the ma- 

 nure, that might be furnished from the various substances annu- 

 ally produced, especially, when he has to transport the gypsum 

 any considerable distance, it being a heavy and expensive arti- 

 cle to move. The expence of manure, as well as every other 

 part of husbandry, should be apportioned to the profits which 

 are to be expected as the probable result. 



Of the dung of domestic animals, most used, horse dung ig 

 believed to be the worst, and that of sheep and swine the best 

 If the former be suffered to he long in a heap, it will be great-- 

 ]y mjured, and may be entirely spoiled by its own heat, whick 

 is to be known by its white mouldy appearance ; and therefore^ 

 if it is lying in a large heap, should be applied as soon as fosii- 

 ble, for spring crops. It is most suitable for cold, wet and stiff 

 soils ; as is that also, of sheep dung, though this is good for any 

 soil. Every kind of barn manure is much injured by being ex- 

 posed to rains, and therefore, should be kept as much under 

 cover as is practicable. The opinion that some farmers have 

 entertamed, that a wet or moist yard for cattle is profitable, be- 

 cause in it, vegetable substances become rotten, or decompos- 

 ed more rapidly and effectually, is very erroneous, and should 

 be exploded. 



It is observed by Mr. Davy, in his agricultural chemistrv. 

 that there has been no question on which more difference of o- 

 pmion has existed, than that of the state in which manure 

 ought to be ploughed into the land ; whether recent, or when 

 It has gone through the process of fermentation ; and this, he 

 observed, was a subject of discussion, so late as 1812. Yet, he 

 IS of opmion, that the knowledge of the simplest principles of 

 chemistry, may remove all doubt on this subject. For, says he, 

 as soon as dung begins to decompose, it throAvs off its volatile 

 parts, which are the most valuable and most efficient. Duno- 

 which has fermented, so as to become a soft, cohesive mass! 

 has generally lost from one third to one half, of its most useful 

 constituent elements. It evidently, says he, should be applied 

 as soon as fermentation begins, that it may exert its full action 

 upon the plant, and lose none of its nutritive powers. He fur- 

 ther remarks, that besides the dissipation of gasseous matter, 

 When fermentation is pushed to the extreme, there is another 

 disadvantage m the loss of heat, which if excited in the soil, is 

 p 2 



