[425] SCIENTIFIC MANUAL. 139 



vegetation effected by moisture absorbed by a finely pul- 

 verized soil. 



The influence of the moisture of the atmosphere is well 

 illustrated in eastern England, where the average annual 

 rainfall is only about half that in Georgia, and yet by 

 the absorption of moisture from the atmosphere, and 

 the prevention of evaporation, twenty-eight inches of an- 

 nual rainfall there, affords a more abundant supply of mois- 

 ture to vegetation than fifty do in Georgia. Of 27.93 

 inches of rainfall at Rothamstead, England, 36 per cent, 

 or 10.06 inches, percolated through 40 inches of earth, 

 while at Waushakum farm, near Boston, Mass., only 4.76 

 inches out of 43.88 percolated through 25 inches of soil. 



In England, 36 per cent, of the annual rainfall peror 

 lated through 40 inches of stifrish clay loam, on which no 

 crop grew, while in Massachusetts only 11 per cent of the 

 annual rainfall percolated through 25 inches of light grav- 

 elly loam, upon which grass grew.* 



The beneficial influence of an abundance of rain and the 

 injurious effects of an excess is well known to every farmer. 

 The rainfall in Georgia is so well distributed throughout 

 the year, that, with the exception of occasional periods of 

 saturation in early spring and drouth in summer, we 

 seldom have an excess, and generally an abundance for 

 agricultural purposes. 



The extremes are seldom so great as to be beyond the 

 control of the skillful agriculturist. 



The most interesting fact in connection with the utiliza^ 

 tion of rainfall is, that the same means viz : Under drainage 

 and deep tillage, serve at once to relieve the soil of surplus 

 water and to fortify against drouth. 



A deficient amount of rainfall maybe supplemented by 

 irrigation, but this is usually accompanied by great ex- 

 pense, and, while it may supply water, it cannot effect a 

 uniform distribution, or rob the atmosphere of its warmth 



*!cien/tiJie\Farmer Measurements from Lysimeter 



