MANURES. 



81 



stracted. The same substances are especially valuable for 

 their poAver 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 tanbark, and in fact all 

 vegetable manures are exceedingly valuable in this re- 

 spect. 



Manures indirectly assist the growth of plants by de- 

 stroying weeds and predatory vermin. This is not a 

 property of animal and vegetable manures, (except that 

 guano repels most insects,) they , foster these enemies of 

 the crop, but salt, lime and ashes applied to the surface of 

 the soil are very destructive to nearly all insects, while 

 the roots of weeds and grasses if composted with the salt 

 and lime mixture are completely destroyed, and converted 

 into an excellent manure. 



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 substances 

 have a tendency to promote the decay of any organic re- 

 mains in the soil. All putrescent substances hasten the 

 process of putrefaction in other organic bodies with which 

 they come in contact. Even peat and tanbark mingled 

 with stable dung, and kept 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. 



\ But the most valuable agent in decomposing organic 



substances is the salt and lime mixture made as follows : 



Take three bushels of unslacked lime, dissolve a bushel 



' of salt in as little water as possible, and slake the lime 



, therewith — if the lime will not take up all the brine at 



'( 

 / 



