MANURES. 23 



having been volatilized or dissipated into the atmosphere 

 in the form of various gases, these composing the major 

 part of the plant food in it. It is the same process that 

 takes place m the combustion of coal or wood, only hi a 

 less and slower degree, the product, heat, being the same. 



The gases, either by themselves or in combination, are 

 fetid, and are evolved as soon as the excrements are 

 voided. When, therefore, manure gives out offensive 

 odors, we may be sure that its gaseous parts are escaping, 

 and that it is losing its fertilizing powers. To prevent this, 

 or to recover them as they are given off, is to economize 

 and add to our stock of fertilizing materials. A similar 

 loss ensues from the evaporation of the liquid parts of the 

 manure, for the water it contains in evaporating carries 

 with it large quantities of these gases, which it absorbs as 

 they are evolved, and retains even when it is hi the form of 

 vapor. Leaching also produces the same effect hence the 

 benefits arising from the use of liquid manure. 



Manures should therefore not be exposed to the action of 

 the weather, for then they lose from one-half to two-thirds 

 of their strength. They should be kept dry, and mixed 

 with such materials as will absorb the gases thrown off in 

 the process of fermentation. To this end it is true economy 

 to provide a good-sized open shed, in which the manure 

 should be kept and prepared for use. 



The best absorbents of the gases arising from the decom- 

 position of the manure, are dry earth, peat, muck, charcoal 

 dust, leaf mould, spent bark and sawdust. Of these dry 

 earth is always to be obtained in summer time, when it can 

 be laid away under cover for winter use. Peat and muck are 

 generally to be had on farms of any extent. They should 

 never be used when fresh dug, but should be thrown up in 

 ridges to be exposed to the action of the air and frost to 



