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special mention. First, surface irrigation where the 

 water is carried over the land by means of surface 

 ditches. The supply of water may be carried to the 

 land either by pumping or by gravity. In order to 

 make this plan effective, the surface of the soil 

 must be gently sloping and smooth in order that 

 the water may be carried over all parts of the area 

 with ease and dispatch. This plan requires large 

 amounts of water and considerable attention to 

 properly direct the water into the various channels 

 in order to secure even distribution. There are 

 many local places to be found, however, admirably 

 adapted to this plan, and under the proper condi- 

 tions none other will be found so cheap and 

 effective. 



Second, sub-irrigation has been tried in various 

 places and a few years ago was hailed as the prob- 

 able solution of this vexing question. It was 

 claimed that the tile used for drainage, if properly 

 laid, could in turn be used for irrigation. It was 

 soon found, however, that in order to make the plan 

 effective from the standpoint of irrigation, the tiles 

 would have to be laid very much closer together 

 and nearer the surface than would give the best 

 results for drainage purposes. The lateral move- 

 ment of the water from the tile is slow and in sandy 

 or gravelly soils the loss of water by percolation 

 is so great as to prohibit the use of this plan, ex- 

 cept where almost unlimited quantities of water 

 are available. Sub-irrigation has many advantages, 

 but it is not to be looked upon as practical, except 

 for very small areas and in locations where the sub- 

 soil comes within two or three feet of the surface 

 and is comparatively tight and impervious. The 

 area should also be comparatively level in order that 



