114 NATURAL MANURES. VI. 



From the preceding tables it will be seen that the excre- 

 ments of the sheep are less watery than those of the other 

 animals, while the solid excrement of the cow and the urine of 

 pigs are richest in water. 



A large proportion of the solid matter in all cases consists of 

 substances comparatively useless as plant food carbonaceous 

 matter, lime and magnesia, silica, &c. Other analyses of the 

 excrements of horses and cows have been published by 

 Boussingault and by Audoynaud and Zacharewicz.* The 

 results expressed in percentages were as follows : 



Boussingault. Audoynaud and Zacharewicz. 



Nitrogen. Potash. ^ Nitrogen. Potash. *$$? 



Cow urine ...1-12 1'39 -97 1-32 trace 



,, dung ... -44 -04 -14 -42 trace -10 



Horse urine ... 1'56 1'06 trace 1*48 -80 trace 



,, dung ... -57 -15 -40 -55 trace -30 



In the paper referred to the authors estimate the annual 

 yield per cow at 31*5 kilograms of nitrogen and 40'8 kilograms 

 of potash in the urine and 42 kilograms of nitrogen, 4-2 of 

 potash, and 12 of phosphorus pentoxide in the dung ; while in 

 the total excreta of one horse per annum w r ill be 37 '8 kilo- 

 grams of nitrogen, 13-1 of potash, and 14-4 of phosphorus 

 pentoxide. 



They think that the potash in dung is that existing in the 

 food as inorganic salts, while that in the urine existed in the 

 food in combination with organic acids. They found a defi- 

 ciency 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 curry- 

 comb and brush contained from 2 to 2' 2 per cent, of potash in 

 the case of cows and from 7'4 to 9*7 per cent, in that of the 

 horses. I A much larger amount of potash is exuded from the 

 skin of the sheep., 



* v. Abst. in Jour. Soc. Chem. Ind. 1886, 541. 



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

 Physiology 11, 497 ; also Jour. Chem. Hoc., 1891, abst. 349) : 

 Water .. .. 94-3776% 



Organic matter . . 0'5288 (chiefly albuminoids) 

 Ash .. .. 5-0936 



/Chlorine .. 0'3300 

 Lime . . 0'0940 



The ash contained -; Magnesia . . G'2195 



Soda . . 0-8265 



I Potash . 1-2135 



