Irrigation By Mejans ot Unde:rground Porous Pipe; 
7 
Fig. 3 represents a sectional view of ground and tile line. It will 
be noticed that at the end of this tile line is an upright section of tile 
called “end riser”. This end riser was constructed by dressing off a 
section of tile and fitting it as shown in Fig. 3 to the horizontal line. 
This raises the end of each horizontal tile line about i foot in height. 
It is then carried at this elevation for one section of tile, (i foot) and 
then given the grade of the connecting line, which is sufficient to bring 
the lower end of the connecting line 2 feet below the surface of the 
ground at the point where the short connecting line joins the next 
long distributing line. In Section No. i, therefore, end risers would be 
found at points B, D, F and H. In Section No. 2 they will be found at 
M, O, R, and T. 
THE TILE 
The purpose of this end riser is to produce a pressure head of ap¬ 
proximately I foot in each tile line before the water passes from the 
same, through the short connecting line, to the next long line. 
The porous tile used for this system of subirrigation was a tile 
manufactured for this purpose by the company. It is impossible to 
state exactly how this tile was made and Vv^hat material was put into 
the same. It was a secret process and the company was not at liberty 
to state the manner of manufacture. It may be stated, however, that 
these tile had the appearance of tile manufactured from cinders, sand 
and cement. They were guaranteed by the company to be porous 
enough to pass water freely, and yet to prevent any roots from entering 
and clogging the same. That they were porous enough to pass water 
was demonstrated, and also that roots from trees and alfalfa did not 
enter and clog the tile was also demonstrated as the experiment 
progressed. 
The tile, however, were very soft. So soft that a great deal of 
difficulty was encountered in transportation. In the first shipment 
made fully one-half of the tile were found to be broken when the car 
was opened. Another shipment was ordered and that arrived in about 
the same condition, so that a third shipment was necessary in order to 
secure sufficient tile to complete the lines planned for the subirrigation 
system. 
The tile were laid in the trench approximately 2 feet deep as 
ordinary drain tile are laid, with this exception, that each joint was 
carefully sealed with cement mortar. These mortar joints are shown 
on Fig- 3 - 
SIZE OF TILE 
The tile can of course be made in any size desired, but the size 
recommended for the ordinary lateral line in a system of this kind was 
2% inches, inside diameter. This makes the tile approximately 4 inches, 
outside diameter. 
