IRRIGATION FARMTXG. 



laid lengthwise of each bed. If the beds are long, it 

 will be well to have a slope at least one inch in thirty 

 feet from the point where the water is admitted. To 

 avoid the over-saturation of the soil, the lower ends of 

 the tiles can extend beyond the ends of the beds, and be 

 so arranged that they can be closed while the water is 

 being admitted, and opened so as to allow all surplus to 

 drain off when a suflicient time has been given the soil 

 to take up the needed water. In this way the soil can 

 also be well aerated, and if bottom heat is desired, one 



FIG. 95. GREENftOUSE IRRIGATION. 



has only to run steam or hot water pipes through the 

 tiles. 



When the beds are to be irrigated, water is poured 

 quickly into the ends of the rows of the tiles, so that it 

 will run the entire length of each row at once, and soak 

 out slowly and uniformly through the adjacent soil ; 

 watering is to be done as often as the plants require it, 

 and their needs are learned in the same manner as by 

 surface watering, but the applications need not be so 

 frequent as by the old plan. It may readily be seen that 

 this system has some advantages. Heretofore the diffi- 



