112 NATURAL MANUKES. VI. 



akin to humus in their nature, these ingredients are of con- 

 siderable importance in determining the effect of farm-yard 

 manure on land. 



The chemical character of the excreta produced on the farm 

 depends upon a number of conditions the food, the breed of 

 animals kept, their age, whether fattening, working, or milk- 

 ing, and other circumstances. 



Obviously, if an animal is growing in size, or is yielding 

 milk, its food must contain much more of the important flesh- 

 forming constituents than its excreta ; while in the case of an 

 animal not increasing in size nor providing milk, one might 

 expect that the excreta would contain practically all the 

 matters taken in its food, with the exception of those con- 

 sumed in respiration. Eemembering these facts, it is not 

 surprising to find among published analyses of the excrements 

 of animals considerable discrepancies. 



The following table gives the percentage amounts of the 

 most important manorial constituents of the excrements of the 

 common animals" : 



Water. Nitrogen. Potash. Ph 8 c ^ 101>ic 



Cattle dung ... -20 -10 -17 



urine ... -58 -49 



Horse dung ... -44 -35 -17 



urine ... 1'55 1-50 



Sheep dung ... -55 -15 -31 



,, urine ... 1-95 2-26 -01 



Pig dung ... -60 -13 -41 



,, urine ... -43 -83 -07 



Hen manure (fresh) 6OO 1-10 -56 -85 



Pigeon manure (dry) 10-0 3'20 1-00 1'90 



Human excrement... 77'2 1-00 '25 1-09 



urine ... 95'9 -60 -20 -17 



The table on the opposite page gives analyses of the excre- 

 ments of the common farm animals and of man. The figures 

 are quoted by Storerf from analyses by Stoeckhardt and Way : 



* U.S. Dept. of Agriculture, Bulletin 15, 1893. 

 t " Agriculture in Some of its Relations to Chemistry," Vol. I. p. 489. 



