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HANDY-BOOK OF HUSBANDRY. 



may be kept locked, (Fig. 45.) When large sizes of vitrified 

 earthenware pipes (ten or twelve inches in diameter) can be ob- 

 tained, they make a very good and cheap silt-basin, answering 

 very well for the collection of several small drains. One of 

 these is shown in Figure 46. 



The most perfect deposit of the silt will be secured in those 

 basins which admit and discharge the water on the same level ; 

 but a difference of two inches — sufficient to allow the action of the 

 in-coming drains to be seen — is so satisfactory to the eye of a 

 proprietor, that it may well be tolerated in basins which are built 

 to the surface, although the fall tends to keep the water in the 

 basin agitated to its bottom, and somewhat interferes with the de- 

 posit of silt. Basins, which can be opened at the surface, should 

 have their outlets protected by coarse 

 wire-cloth or upright grating, to pre- 

 vent the entrance of rubbish, which 

 may, by accident, reach them. 



The position and size of all under- 

 ground silt-basins should be carefully 

 noted on the map. In the event of 

 the stoppage of any drain, (which will 

 be indicated by the wetness of the 

 ground), dig down to the first silt-ba- 

 sin below the break, and the cause will 

 generally be found to be the accumu- 

 lation of silt beyond the capacity of 

 the basin, and, by taking up a few tiles 

 each way from it, until they appear 

 free from deposit, the difficulty may 

 be remedied in far less time than 

 would have been necessary if the silt 

 had been allowed to deposit itself 

 through a long stretch of the drain. If the soil is very " silty," 

 (containing layers of running quicksand,) the ditch immediately 

 over the silt-basin should be left open for a short time after the 

 drain is laid, so that, by simply removing the stone cover, the 



Fig. 45. — Silt-basin, built to the surface. 



