ON LAWN BEAUTIFICATION 



and then, and if they are not too large they will 

 sometimes be flushed during heavy rains when 

 they are filled to capacity. This flushing serves to 

 keep them clean and the flushing produced natur- 

 ally when small tiles are used is sufficient reason 

 for recommending the smaller sizes rather than 

 larger ones which are more expensive and gen- 

 erally less efficient. 



The general impression is that cracks should be 

 left, and sand put in the cracks. The real way is 

 to surround the joints with clay; then they are 

 permanent. The worst thing to do is to put sand or 

 gravel or straw about the cracks. A tile four feet 

 deep will drain twice as wide an area as a tile two 

 feet deep. About four feet is the proper depth. 



The strength of the entire system depends upon 

 the weakest section. Therefore it is necessary in 

 laying the tile to examine carefully each piece, and 

 to see that they are well burned, but not sufficiently 

 to make them impervious. The system must be 

 laid upon the proper grade, for if the line sags, 

 sediment will collect and retard the flow of water. 



It is best to make a silt basin at some point 

 where the branching tiles unite. This is formed 

 by digging down a foot or two, and bricking or 

 cementing up a barrel-like receptacle, the entrance 

 pipe from the main system being a little lower 

 than the exit pipe, so that the silt settles. 



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