ANIMAL MANURES. 117 



I he liquid is deficient in phosphates, the solid excrement 

 contains a large amount of these valuable compounds. Botli 

 together aftbrd us all the elements necessaiy for the develop- 

 ment of plants. The fresh dung of the cow and horse hac? 

 respectively the following composition in the 100 parts: — 



Cow, Hone. 



Water 79.724 ... 78.36 



Orj^anic matters 1G.046 ... 19.10 



Saline matters 4.230 ... 2.54 



The composition of the saline matters of each in the 1 00 

 parts is as follows: — 



Cow dung. Horse dung. 



Phosphate of Lime 10.9 ... 5.00 



Phosphate of Magnesia 10.0 ... 36.25 



Carbonate of Lime ... 18.75 



Phosphate of Iron 8.5 



Carbonate of Potash 1.5 



Sulphate of Lime 3.1 ... 



Silica C3.7 ... 40.00 



Loss 2.3 ... 



100.0 lOO.UO 



169. The dung of the cow, however, usually contains a 

 larger amount of water than stated in the above analysis ; 

 and as the chief portion of the nitrogen contamed in its food 

 is separated in the urine, it does not so readily run into 

 fermentation, and is correctly regarded as aflbrding a colder 

 manure than horse-dung. The quantity of solid matter, 

 you have seen, which is annually voided by the horse in 

 the urine, does not amount to one-tenth part of that which 

 is contained m the urine of the cow; and as the food whicii 

 the former animal receives consists chiefly of the dry and 

 nutritious grains, its solid excrement rapidly decomposes, 

 and gives out much heat when placed in the soil; and 

 hence it is frequently mixed with other manures for the 

 purpose of inducing fermentation. From the rapidity with 

 which it decomposes, much of the valuable qualities of horse- 

 dung are usually lost to the farmer by allowing it to accumu- 

 late in the stable or farm-yard. Boussingault found that 

 fresh horse-dung which, deprived of water, contained in tlu* 

 100 lbs. so much as 2^tb3. of nitrogen, lost by fermentation 



