236 FARMYARD MANURE [chap. 



cake only showing a superiority of 7 per cent, over the 

 other. In slow- acting nitrogenous constituents the 

 two lots of manure were alike ; the difference chiefly lay 

 in the ammonia, which had its effect in the first year, 

 but was not effective afterwards. 



Analyses Nos. 5, 6, and 7 show the change of com- 

 position that dung undergoes on storage. There is a 

 gradual increase in the percentage of nitrogen, because 

 the original material has lost carbon compounds more 

 rapidly than nitrogen, so that the percentage of nitrogen 

 in the remaining material shows an increase. At the 

 same time, from other analyses we learn that in very old 

 short dung but little of the nitrogen remains in a 

 soluble form or combined as ammonia. Analyses 8 and 

 9 show the composition of the manure that is obtainable 

 from London, in the one case made with peat-moss 

 litter and in the other with straw. The peat-moss 

 manure is not only richer in nitrogen because of the 

 nitrogen in the peat moss itself, but it retains a much 

 higher proportion of the nitrogen in an ammoniacal state 

 because of the absorptive power of the peat for 

 ammonia. 



From a consideration of the origin of the losses of 

 nitrogen which take place during the making of dung, 

 and of the above analyses, a good deal of guidance can 

 be obtained as to the practical management of farmyard 

 manure, which remains the fundamental fertiliser in 

 the ordinary course of farming in this country. In the 

 first place, since it is clear that the most valuable part 

 of the manure resides in the liquid, far more care should 

 be taken to preserve this than is usually the case. 

 Whether the dung is made in boxes or in yards, there 

 should be sufificient depth to allow the manure to 

 accumulate under the animal for the whole winter if 

 need be, and the floors should be rammed with clay to 



