[363] SCIENTIFIC MANUAL. 77 



of the results of which is the evolution of this gas, facili- 

 tates the decomposition of the lime, renders it soluble, and 

 hence increases its distribution in the soil. 



Caustic lime, however, is freely soluble in water, and is 

 not only readily distributed through the soil, but rapidly 

 carried down beyond the reach of vegetation. 



Since quick-lime is soon converted into the carbonate in 

 the soil, its chemical effect differs but little from that of 

 chalk or marl, but, being more finely divided, is more act- 

 ive and available. 



Lime, besides acting directly as plant-food, and chemic- 

 ally in the preparation of other substances, exerts also an 

 important influence as a mechanical agent. 



Sulphuric acid, carbonic acid, ammonia, and potash, also 

 act both as direct plant food, and as chemical agents. 



The interest of farmers demands the most economical 

 means for both plant and soil fertilization, which should, as 

 far as practicable, be combined. For this purpose, the 

 pea-vine and lime in some form, together with compost of 

 cotton seed, animal manures and superphosphate, furnish at 

 present the most promising sources for the farmers of 

 Georgia. Marl is locally accessible in a large portion of 

 Southern Georgia, and quick-lime in all of Northwest 

 Georgia, and, indeed, may be readily transported to almost 

 any part of the State at reasonable rates, as soon as it is 

 used in sufficient quantity to justify its being quarried and 

 burned on a large scale. 



COMPOSTS. 



Georgia produces annually about 17,500,000 bushels, or 

 525,000,000 pounds ot cotton seed. About 2,01)0,000 

 bushels are required for planting the crop, leaving 15,500,- 

 000 bushels- 232,500 tons of seed to be used for manurial 

 purposes. If the whole of this was composted with ani- 

 mal manure and superphosphate, according to the formulae 

 published in the circulars of this Department, there would 

 be produced 620,000 tons of compost ; enough to manure, 



