THE DRAINAGE OF THE FAUM, 4()9 



that distance ; hence, one of the best guides in cutting a drain is to observe 

 whether or not the water (when of course there is any), leaves you as 



The kind of draining materials to be used, must depend very much on 

 the comparative prices at which they can be obtained in the district; but, 

 other things being equal, circular pipes inside are preferable to any other 

 kind. As the water runs in a contracted channel, there is less chance of 

 a pipe-drain being choked by the deposition of sediment, than there is in 

 case of horseshoe -shaped or flat-bottomed tiles, in which the water is 

 so much spread that it has not the power of washing away a deposit. The 

 - of the pipes should be determined according to the estimated di<- 

 charge from any particular field about to be drained. In long drains a 

 larger sized pipe should be laid at the lower than at the upper ends. For 

 150 yards, at the highest part of each drain, \\ -inch pipes will be found 

 MI i table ; but, if there is likely to be much water, 2 and 3-inch pipes are 

 small enough for the principal parts of the drain. Wherever the bottom 

 is soft or uneven, it will be advisable to use collars ; and in that way, a 

 smaller >i/ed pipe will do than if there were no collaring only it is cer- 

 tainly advisable, as I have already said, to make the soil collar the pipe, 

 in all cases where this may be practicable. 



Care should be taken to lay the pipes as soon as possible after the 



drain is cut. The bottom is liable to become soft, and be more or less cov- 



1 with mud, if there is any considerable delay. In putting in the 



pipes, it is advisable, in wet weather, to keep closely up to the drain- 



cutter ; and the laying work must be done by day's wages, and not by 



contract. No drain ought to be laid till the owner is satisfied that it is 



tlv formed : and, after the pipes are put in, he must inspeet them \ 



fully before the tilling is commenced. Should he, in making this 



rye any open joints in the tiles, he should lay a small] 

 upon it. 

 Then- are various modes of filling the drains in use in different di-: 



ill allow nothing but a paring of the surface sward t. 

 t the pipes; other, prefer broken -tones, or gravel; and a third 

 insider elay the U-st of all coverings. In respeet to the use of sur- 

 face soil, it may only In- remarked that, as it is a dirtier MiKstanre than 

 .1 fouls \vatermuehmore than it does, it is not a suitable < 



g through it, is likely to carry more injurious matter into 



:i, than would he the case w B a clay e 



s resulting from the removal of the soil from the surf.nv is not 

 ble . and nut pern-late K readily tin 



