42 The Drainage of Fens and Low Lands. 



as low as the pipes, the cavities made in their progress acting 

 most effectually as feeders to the drains. 



Thoroughly drained fields stand wet and drought better than 

 undrained fields of the same sort of soil From the principles 

 already laid down, it is evident that this should be the case. 

 It is well known by those who have paid attention to the 

 matter, how during protracted droughts the thoroughly drained 

 fields call attention to themselves by their superior verdure. 

 By their improved texture they are not liable to become 

 baked, and the free soil is in a condition to take in a supply 

 of moisture from the dews of the summer night, which the 

 hard diy skin of the undrained land is incapable of doing. 



Thoroughly drained fields are also more easily tilled, and 

 are in a fit state for the operation of tillage a much greater 

 number of days in a year. 



Time to Drain. — The time of the year chosen for putting 

 in drain-pipes must be regulated by the cropping and other 

 circumstances ; but it may be stated that the drier the 

 weather the better for the drainage. In clay soils, the drying 

 action of the air and wind on the trenches allows the soil to 

 contract and form the crevices necessary for the rains to 

 escape to the drains. Experienced drainers recommend the 

 month of February for the work, and that the pipes receiving 

 a light covering of soil, should be left open through March, 

 if it be drying weather, by which means the cracking of the 

 soil is much accelerated, and the complete action of the drains 

 advanced a full season. 



In laying drains in a silty soil, the worst time to choose is 

 when the ground is full of water ; the feet of the men working 

 in the grips cause the silt to purge, so that it is impossible to 

 get a good and even bed to lay the pipes on ; and even when 

 laid they are extremely liable to choke, by the loose silt in the 

 trenches being washed in by the water which pours out of the 

 ground If the pipes are laid when the silt is dry, or only 

 slightly wet, the bottom of the trenches may then be taken 



