138 SUCCESSFUL FARMING 



breeding places for mosquitoes, and caused their disappearance to such a 

 degree that malaria is now practically unknown in that region. 



Open vs. Underground Drains. — The gravitational water in the soil 

 may be lowered to the depth of two or three feet below the surface by 

 open drains, but the same can be more economically effected by the installa- 

 tion of underground drains. Open drains waste much land, the ditches 

 are subject to erosion and their presence interferes with cultural opera- 

 tions. They are also expensive to maintain, because of the necessity of 

 annually cleaning them. 



Underground or tile drains are more effective than open ones. They 

 waste no land, require practically no outlay for annual maintenance, do 

 not interfere with cultural operations and are permanent. The cost of 

 excavating for underground drains is less than that for an equal length 

 of open drains, because in the former very narrow trenches are excavated 

 which are filled as soon as the tile is in place. 



Q.uality of Tile. — Burned clay pipes are almost universally used for 

 soil drains. They are made in sections, from 12 to 24 inches long, having 

 an internal diameter ranging from 3 to 16 inches. Since the installation 

 of underground drainage is to be permanent, care should be exercised in 

 the selection and purchase of the tile. Only the straight, well-burned 

 tile should be used. A well-burned tile is generally dark in color, and 

 gives a decided ring when struck with a light metal. Formerly it was 

 thought that such tiles should be quite pervious to water, but it is now 

 understood that the openings at the joints are ample to admit the water 

 from the soil as fast as it can reach the lines of tile. 



Cost of Tile and Excavating. — The cost of installing underground 

 drainage depends on the cost of the tile laid down on the land, the fre- 

 quency of the underground lines of drainage as determined by the per- 

 meability of the soil to water, together with the cost of digging the trenches 

 as determined by the ease or difficulty in excavating the soil. The cost 

 of the tile will vary with the locality, the freight charges and the distance 

 they must be hauled. In general, the price of the tile per 1000 feet F. 0. B. 

 cars, at the factories, will be as follows: 



Size. Price. 



3 inch $10. 00-812. 00 



4 " 15.00-20.00 



5 " . 20.00- 27.00 



6 " : 27.00-35.00 



7 " 36.00-50.00 



8 " 45.00- 60.00 



10 " 60.00-110.00 



12 " 90 . 00-150 . 00 



The cost of digging the trenches will vary greatly with the character 

 and condition of the soil to be excavated, the skill of the digger and the 

 prevailing cost of labor in the locality. Deep trenches cost relatively 

 more to excavate than shallow ones, because the trenches must be wider 



