12 On Liquid Manure. 



withstanding the larger amount of organic matter, it contains 

 very much less ammonia. A somewhat smaller proportion of 

 ammonia might have been expected, since cows' urine, which 

 entered largely into its composition, is much poorer in nitrogen 

 than horse-urine, which chiefly composed the liquid manure 

 from Westonbirt. However, the quantity of ammonia (only 

 11-41 in a gallon) is so inconsiderable that the differences in the 

 proportion of the original liquids which chiefly composed these 

 two kinds of liquid manure are altogether insufficient to account 

 for the small quantity of free ammonia in that from Badminton. 

 This liquid, having been kept in an open tank for more than 

 three years, has evidently lost by evaporation carbonate of 

 ammonia, which we have seen is rapidly formed during the 

 decomposition of urea. That this really was the case was proved 

 by the small quantity of carbonate of ammonia which was left 

 in it. During the long time it was kept in the tank the 

 volatile carbonate of ammonia had every chance of escaping. 

 We may thus learn that it is not advisable to preserve liquid 

 manure for a long period, and that the safest plan is to fix the 

 ammonia at once by the addition of some sulphuric acid. 



The organic matters left on evaporation of both kinds of 

 liquid manure presented the same characters, and both contained 

 an identical percentage of nitrogen. Thus 155'44 grains of 

 organic matters contained in that from Westonbirt yielded on 

 analysis 4*78 grains of nitrogen, whilst 239*32 grains of organic 

 matters found in the Badminton liquid furnished 8 '98 grains. 

 This gives for 100 parts 3'75 grains of nitrogen for each of 

 the two samples. No appreciable difference is observable in 

 the composition of the mineral portion. The ash of the Weston- 

 birt manure, like that of the Badminton liquid, is rich in salts of 

 potash and is greatly deficient in phosphoric acid. 



3. Liquid Manure from the Royal Agricultural College Farm, 

 Cirencester. Collected in 1 857. 



The liquid-manure tank on the College Farm is placed close 

 to the manure-pit, in which stable manure, cows' and pigs' dung 

 are collected together. It is of a sufficient capacity to hold, in 

 addition to the drainings from the manure-pit and stables, the 

 sewerage from the College. Animal refuse matters, such as the 

 blood of animals killed on the farm, the carcases of dead sheep, 

 lambs, &c., are thrown into the liquid manure-tank ; and by these 

 additions no doubt the fertilising properties of this kind of liquid 

 manure are greatly increased. 



