FARM DRAINAGE. 65 



digging would be more than balanced by the fact that the 

 drains could be put farther apart. I should not be deterred 

 from draining, however, even though the stone came so near the 

 surface that I could only lay the tile twenty inches deep. I 

 have tiles laid at this depth that have done good service for 

 twenty years and have never given me any trouble. 



As to the distance apart, I am inclined to think that the 

 usual directions call for more drains than are necessary. War- 

 ing in his book on drainage recommends "that drains four feet 

 deep be laid from forty to fifty feet apart and on retentive clays 

 even as close as eighteen feet, and that there are few soils 

 which need draining at all on which it will be safe to place four 

 foot drains at much wider intervals than forty feet." Professor 

 Mapes says " three-foot drains should be placed twenty feet 

 apart, and for each foot added to the depth the distance may be 

 doubled." 



Mr. Billingsly in his recent work on drainage says : " In 

 our experience, drains placed one hundred feet apart on loamy 

 soils and three and a half feet deep, will thoroughly drain the 

 soil. If, however, the soil is very retentive, especially near the 

 surface, a distance of fifty to seventy-five feet may be required 

 to give thorough drainage." So far as my own experience 

 goes I should agree with Mr. Billingsly rather than the other 

 authors quoted. I have on my own farm had the fact demon- 

 strated that a drain but two feet deep will affect the land to a 

 greater distance than is commonly supposed. The subsoil on my 

 farm is a stiff, yellow clay, and in my earlier draining I laid my 

 laterals two rods apart, as I could only place them two feet 

 deep. Near the head of my drains which flow south-east, we 

 reach a level, and in a few rods the land falls to the north-west, 

 and here I have another line of tile running to the north-west, 

 the head of it being twenty rods from the head of the drain 

 flowing in the opposite direction. Immediately north of the line 

 of drain which flows south-east, and east of the head of the drain 

 which flows to the north-west, is an acre of land belonging to a 

 neighbor and which is about eight inches lower than my land 

 south and west of it. Before I put in these drains this land 



