18 FARMYAED MANURE. 



of August, 27*9 per cent, of the total amount of nitrogen, or 

 nearly one-third of the nitrogen in the manure, has been wasted 

 in one way or the other. 



It is worthy of observation that, during a well-regulated fer- 

 mentation of dung, the loss in intrinsically valuable constituents 

 is inconsiderable, and that in such a preparatory process the 

 efficacy of the manure becomes greatly enhanced. For certain 

 purposes fresh dung can never take the place of well-rotten dung. 

 The farmer will, therefore, always be compelled to submit a 

 portion of home-made dung to fermentation, and will find satis- 

 faction in knowing that this process, when well regulated, is not 

 attended with any serious depreciation of the value of the manure. 

 In the foregoing analyses he will find the direct proof that, as 

 long as heavy showers of rain are excluded from manure heaps, 

 or the manure is kept in waterproof pits, the most valuable fer- 

 tilising matters are preserved. But let us now see how matters 

 stand when manure heaps, the component parts of which have 

 become much more soluble than they were originally, are exposed 

 to heavy showers of rain. 



In the first experimental period little rain fell, and this never 

 in large quantities at a time, whilst in the interval of April and 

 August rain was more abundant, and fell several times in con- 

 tinuous heavy showers. In consequence of this soluble matters 

 in the heap were washed out, and with them a considerable 

 portion of available nitrogen, and the more valuable mineral 

 constituents of dung were wasted. 



The above analytical data, if I am not mistaken, afford like- 

 wise a proof that even in active fermentation of dung but little 

 nitrogen escapes in the form of volatile ammonia, but that this 

 most valuable of all fertilising materials, along with others of 

 much agricultural importance, is washed out in considerable 

 quantities by the rain which falls on the heaps, and is wasted 

 chiefly in the drainings of the dungheaps. 



A single fact, it has been truly said, is worth more than a 

 dozen vague speculations. We hear frequently people talk of the 

 loss in ammonia which farmyard manure undergoes on keeping, 

 and this loss is referred by them to the volatilization of the am- 

 monia which is produced in the putrefaction of the nitrogenized 

 constituents of dung. I have, however, already mentioned that 

 simultaneously with the ammonia, ulmic, humic, and other 

 organic acids are generated from the non-nitrogenized consti- 

 tuents of manure, and that these acids possess the power of 

 fixing the ammonia in an excellent manner. If this were not the 

 case, it would be difficult, if not impossible to explain the cir- 

 cumstance that the proportion of soluble nitrogenized matters 

 increased considerably in the manure on keeping for a period of 



