86 The Principles of Vegetable- Oardening 



is thereby looser or more friable. This friable condi- 

 tion of the soil enables it to hold more moisture 

 than when it is hard and brick -like. It therefore 

 results that draining to remove the superfluous water 

 puts the soil in condition to hold more capillary mois- 

 ture in its own tissues, and improves it for agricultural 

 purposes. For vegetable -gardening purposes, particu- 

 larly^ if quickest results are desired, it is necessary to 

 underdrain hard clay lands, even if they are not wet. 

 It makes them workable early in the spring after rains, 

 and enables the plants to obtain a quicker foothold. 

 These same lands might be used for orchards, how- 

 ever, without underdraining, and they might also be 

 very productive of some general farm crops ; but in 

 such cases the crops may occupy- the land for a term 

 of years, and very quick and early results are not 

 essential. 



For temporary purposes, surface drains may be 

 used, or the land may be ridged so that the surface 

 water is taken off in the dead -furrows. This surface 

 drainage, however, results only in carrying off super- 

 fluous water and does not have the effect of amelio- 

 rating the land in the way in which underdrains do. 



In nearly all cases, it is better and cheaper in the 

 end to use tile underdrains. Board drains are some- 

 times used, but they are not so efficient nor so per- 

 manent ; and in the East they are often more expen- 

 sive to begin with than the tile drains are. In stony 

 countries, excellent drains may be made by partially 

 filling the ditch with stones, particularly if flat stones 

 are to be had so that a conduit can be laid in the 



