VI. 



MANUEING AND GENEEAL MANUEES 



109 



urine existed in the food in combination with organic acids. They 

 found a deficiency of potash in the excreta, even after allowance for 

 that removed in the milk of the cows and the growth of the bodies of 

 the animals. They account for this by attributing it to loss through 

 the skin. The dust removed from the skin by currycomb and brush, 

 contained from 2 to 2*2 per cent of potash in the rase of cows and 

 from 7'4 to 9'7 per cent in that of horses. 1 A much larger amount of 

 potash is exuded from the skin of sheep. 



The " kraal manure " of S. Africa consists of the excrement of 

 animals kept (generally only during the nights) in enclosures, mixed 

 with a little soil, but with little or no litter. Analyses of air-dried 

 deposits from sheep kraals were made by Croghan 2 in 1905, who 

 found, in twenty-five samples, figures ranging as follows : 



Nitrogen . 



Potash 



Phosphorus pentoxide 



0-55 to 1-68, mean 1-22 

 1-23 to 5-86, 3-85 

 0-38 to 1-28, 0-78 



The composition of the excreta of animals is liable to such 

 enormous variations in composition, according to the nature of the 

 food and other conditions, that it is almost impossible to give any 

 average figures. 



As showing how variable the utilisation of the ingredients of food 

 may be, in the case of animals living under different conditions, the fol- 

 lowing table may be quoted from Warington 3 as giving the destination 

 of the nitrogen supplied in the food. For every 100 Ib. of nitrogen 

 consumed 



As has already been stated, the dung consists mainly of the undi- 

 gested portion of the food mixed with a certain amount of the residue 

 from the bile and other digestive fluids. It is therefore to be expected 



1 An analysis of the perspiration of a horse was published by Smith (Journal of 

 Physiology, 11, 497 ; also Jour. Chem. Soc., 1891, Abstracts, 349) : 



Water 



Organic matter 

 Ash . 



0-5288 

 5-0936 

 ^Chlorine 

 Lime 



The ash contained^ Magnesia 

 Soda 

 ^Potash 



'> Brit. Assoc. Report (S. Africa), 1905. 



94-3776 per cent. 



(chiefly albuminoids) 



0-3300 per cent. 

 0-0940 

 0-2195 

 0-8265 

 1-2135 



' Chemistry of the Farm. 



