[411] SCIENIIFIC MANUAL. 125 



seasons, and baked in time of drouth. Drainage removes 

 the surplus water, increases the area in depth which the 

 roots may occupy, admits a free circulation of air, and, 

 hence, a full supply of oxygen to the roots, and prevents 

 the baking of the soil in times of drouth, while moisture 

 and fertilizing gases are absorbed from the air. Again the 

 water line being lowered, rain water, impregnated with am- 

 monia and fresh oxygen, carries these and its warmth into 

 the soil to refresh the roots of plants. Again, as in the 

 case of the surface water, the evaporation is reduced by 

 the removal of the " water line " to a greater depth. 



3. By removing surplus water, and lessening the evapo- 

 ration from the surface, warm air and rain water are allowed 

 free access to the depth at which the drain is laid, and con- 

 sequently the soil is warmed, as well as dried, ear- 

 lier in the spring, and, by affording earlier the necessary 

 conditions of germination, the season of growth is practic- 

 ally lengthened. Every farmer has observed that gravelly 

 or loamy soils, that are naturally underdrained, can be 

 planted from ten to fifteen days earlier than stiff clays, 

 which hold the surplus water from the heavy spring rains. 

 This is just the difference between drained and undrained 

 lands. Ten days difference in the date of maturity of two 

 fields of wheat, will often determine the question of success 

 or failure. Rust is the greatest enemy of the wheat crop 

 in Georgia. 



The only safeguards against this are early maturity and 

 thorough drainage. Ten days differen9e in the time of 

 planting corn will often enable the earlier planting to escape 

 a ruinous drouth. 



The market gardener who gains ten days in the maturity 

 of his products, by having his lands thoroughly drained, 

 will soon drive his less progressive neighbors out of the 

 market. 



4. It deepens the soil, by allowing the rapid percolation of 

 water, a free circulation of air, the deep penetration of roots 



