FBETILIZEKS AM) MANURES. 



57 



acid, which is renewed as quickly as it is abstracted. 

 The same substances are especially valuable for their 

 power of absorbing ammonia. Charcoal will absorb 

 ninety times its volume of ammoniacal gas, which can 

 be separated by simply moistening it with water. 



Decayed wood absorbs seventy times its volume, while 

 leaf-mould, perfectly rotted tan-bark, and, in fact, all 

 vegetable manures, are exceedingly valuable in this 

 respect. 



Another indirect action of manure in assisting the 

 growth of plants is in decomposing and rendering available 

 any stubborn organic substances in the soil. Stable 

 manure, and all decomposing animal and vegetable sub- 

 stances, have a tendency to promote the decay of any 

 organic remains in the soil. All putrescent substances 

 hasten the process of putrefaction in other organic bodies 

 with which they come in contact. Even peat and tan- 

 bark, mingled with stable dung and Tcept moist, are converted 

 into good manure; common salt in small proportions has 

 a similar septic property, and the efficacy of lime in this 

 respect is well known. 



Ashes are of equal value, but not so easy to obtain in 

 sufficient quantity. Neither ashes nor lime should ever be 

 mixed with manures that are rich in ammonia, such as 

 cotton seed or animal manures, as they would cause great 

 waste of ammonia by setting it free and permitting it to 

 be lost in the atmosphere. 



Inorganic substances are sometimes released from their 

 combinations, and rendered soluble by the application of 

 carbonaceous manures. Ashes from which the soluble 

 potash has been leached, if composted with swamp muck, 

 are enabled to furnish plants with a further supply. By 

 composting the two the value of both is greatly increased. 

 Such a compost may be mixed with ammoniacal manures, 



