Farmyard and Green-Manures 121 



contains all of the manurial ingredients. The water is of 

 no particular value ; it simply increases the cost of han- 

 dling. The dry matter consists of 10 to 12 per cent of ash, 

 and from 12 to 15 per cent of organic matter. The ash 

 contains from 8 to 10 pounds each of phosphoric acid and 

 lime, and 6 to 8 pounds of potash; while the organic 

 matter contains from 8 to 10 pounds of nitrogen. 



Its indirect value, however, is often quite as great as, 

 and frequently greater than, its direct value, first, 

 because of its vegetable matter, which materially improves 

 the absorbing and retaining power of soils; and, second, 

 because of the lower forms of life, or bacteria, contained 

 in it, which induce useful fermentations in the soil. Not 

 including the lime, the average ton of city manure con- 

 tains but 28 pounds of actual fertilizer constituents. 



Solid and liquid portions. 



The nitrogen digested from the food, as well as a large 

 part of the potash, is found in the liquid portions of the 

 manure; while the nitrogen in the undigested portions, 

 as well as a large part of the phosphoric acid, is contained 

 in the solid residue. The nitrogen in the urine is largely 

 in the form of "urea," a compound soluble in water, and 

 is easily decomposed ; the potash is also soluble in water. 

 These constituents are, therefore, the most active. 



Sources of loss in manures. 



Manures are susceptible to two direct sources of loss, 

 the first of which is due to fermentation, which results in 

 the loss of nitrogen; and the second is due to leaching, 

 which may finally result in a loss of all of the constituents, 

 though it is confined largely to the soluble nitrogen and 

 potash. By fermentation, the nitrogen in the manure is 



