32. HOW FILM WATER IS PREVENTED FROM EVAPORATING BY 

 A SOIL MULCH 



The water drawn up from the pan by this soil has been stopped by the shallow layer of 

 loose soil on top. Thus it is in the field illustrated below 



33. CORN LEAVES CURLIN'G IN A DROUGHT 



A soil mulch has been made. How to furnish crops with an adequate and equable supply 

 of water is one of the greatest problems of the farm 



