56 GARDENING FOE THE SOUTH. 



in the case of the absence or deficiency of lime, the soil is 

 practically sterile. 



4. "It tends to secure the proper conditions of nitrifica- 

 tion whereby the inert nitrogen of the soil is rendered 

 available. 



5. "It exerts a most important influence upon the 

 flocculation, and therefore upon the tiHabiiity of the 

 soil."* 



The Indirect Action of Manures. — Some manures 

 ameliorate the soil by absorbing and retaining moisture 

 from the atmosphere. This property is as beneficial to 

 a clay as to a sandy soil during drought, as at such times 

 clays are often baked so as to be impervious to the dew, 

 and suffer nearly or quite as much as more sandy soils. 

 The best absorbents of moisture are stable manure, thor- 

 oughly decomposed tan-bark, and the manure of the cow 

 and pig, in the order named. After these come sheep and 

 fowl manure, salt, soot, and even burnt clay is not with- 

 out its virtue. All these absorbents are much more effec- 

 tual when finely divided, and the soil itself is a good 

 absorbent in proportion to its richness, fineness, and the 

 friability produced by frequent culture. In the power of 

 retaining moisture absorbed, pig manure stands pre- 

 eminent; next that of the horse, then common salt and 

 soot. 



Some manures are beneficial in absorbing not only 

 moisture, but nutritious gases from the atmosphere, 

 which they yield to the roots in a concentrated form. All 

 animal and vegetable manures have the power of attract- 

 ing oxygen from the air during decomposition. Charcoal 

 and all carbonaceous matters have the power of absorb- 

 ing carbonic acid gas in large quantities, supplying con- 

 stantly to the roots of plants an atmosphere of carbonic 



"Cotton Production— Tenth Census, 



