36 ANALYSES OF FARMYARD MANURE. 



Analyses of farmyard manure. It is chiefly to the 

 valuable researches of the late Dr Augustus Voelcker 

 that we owe our knowledge of the composition of old 

 and fresh farmyard manure. All interested in this 

 important question should peruse the original papers 

 on this subject contributed to the 'Journal of the 

 Eoyal Agricultural Society ' by Dr Voelcker. Typical 

 analyses illustrating the variation in the composition 

 of farmyard manure at different stages of decomposition 

 will be found in the Appendix. 1 From what has been 

 already said, it is obvious that the composition of 

 farmyard manure is of a very variable nature. 



The quantity of moisture naturally varies most, and 

 this variation will depend on the age of the manure, 

 and the conditions under which it is permitted to 

 decay. It may be taken at from a minimum of 65 per 

 cent in fresh, to 80 per cent in well-rotted manure. 

 The total organic matter may be taken at from 13 to 

 14 per cent; containing nitrogen, .4 to .65 per cent. 

 The total mineral matter will range from about 4 to 

 6.5 per cent, containing of potash from .4 to .7 per 

 cent, and of phosphoric acid from .2 to .4 per cent. 2 



As Mr Warington 3 has pointed out, one ton of 

 farmyard manure would thus contain 9 to 15 Ib. of 

 nitrogen, about the same quantity of potash, and 4 to 9 

 Ib. of phosphoric acid. These quantities of nitrogen 



1 See Appendix, Note XII. , p. 60. 



2 See Heiden's Diingerlehre, vol. ii. p. 156. 



3 Warington, Chemistry of the Farm, p. 33. 



