430 IRRIGATION FARMING. 



signed to carry off all surface water." The water 

 which naturally fell from the heavens was caught in 

 these trenches and filtered one from the other in such 

 a way as to render the subsoil constantly moist and 

 friable. Mr. Cole said: "The advantage of such a 

 system for market gardening will commend itself to 

 those who grow or aim to grow large and valuable crops 

 upon small areas of land." 



Greenhouse Irrigation. — This is the modern idea 

 in greenhouse construc5lion, and the writer is impressed 

 with the system described by Professor L. A. Taft, in 

 the American Agriculturist, and shown by sec5lional 

 view in Fig. 109. 



A durable greenhouse bench for subirrigation can 

 be built of cement, at small cost, especially if it is to be 

 at the same level as the wall. When the bed is desired 

 at the hight of three or more feet, supports must be 

 provided. When the natural level of the soil is where 

 the bottom of the bed should come, one has only to 

 excavate walks, and run up the walls. In a house 

 twenty feet wide it will be easier to make two wide 

 benches, with a walk in the center and two quite nar- 

 row ones next to the outer walls of the house. Having 

 provided for benches, the subirrigation may be secured 

 by means of two or three rows of two and one-half inch 

 drain-tiles 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 admit- 

 ted. 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 



