i88 N. J. Agricultural Experiment Station, Bulletin 348 



vide, in case the outlet cannot be large enough to insure a prompt 

 run-off, for such a lowering of the water table that at least 6 inches 



Fig. 121. Drainage of an open swamp. A, before; B, after. 



of dry soil will be formed in the course of a few weeks' operation 

 of the ditching systems. 



