MANURE. 173 



tatoes grew rank and watery, and on turnips the 

 effects were only half as good, as mere un fermented 

 dung. The circumstance of the soil in this last case, 

 was probably a deficiency of geine. 



247. The liquid evacuation of the horse is com- 

 posed of 



Water, 94- 



Urea, -7 



Chalk, 1-1 



Carbonate of soda, *9 



Hippurate of soda, 2*4 



Muriate of potash, *9 



The hippuric acid is not peculiar to the horse. 

 The urine of most herbivorous animals contains hip- 

 purate, formerly called benzoate of soda, its acid 

 having the fragrance of gum benzoin. If man takes 

 benzoic acid, hippuric replaces uric acid in the urine. 

 According to the composition, horse stale, pound for 

 pound, is equal the value of cow dung. 



248. But rich as are the liquid evacuations of 

 the stable and cow yard, they are surpassed by those 

 of the farmer's own dwelling, especially when it is 

 considered with what ease these last may be saved. 

 According to Dr. Thomson, 1000 parts of this sub- 

 stance, the human liquid evacuation, contain 42 1-2 

 lbs. nearly of salts, which are, 



15* 



