38 PRACTICAL FORESTRY. 



We have in the early part of tin's section drawn 

 attention to the discharge of open drains into the pipe 

 system already existing. This may be, and will be 

 sometimes, found the most convenient method of dis- 

 charging the water from the whole or portion of the 

 forest area to be drained. We strongly advise the 

 forester not to adopt it if he can avoid it. If he 

 cannot, he must take precautions to prevent the debris 

 from the open drains stopping the pipes. This can 

 be best done by building with bricks or stone a well 

 at the point of discharge deeper than the inlet to the 

 pipe, which permits of the collection of soil and heavy 

 debris ; and by hanging an iron grating in front of 

 the pipe branches and leaves are also kept back. 

 These wells should be frequently cleared. If this 

 plan is resorted to there need be little fear of stoppage. 



The cost of forest drainage will be a matter of 

 concern, but to say that it will cost so much is simply 

 beyond our power. It will depend entirely upon the 

 soil to be drained, and the obstructions met with, in 

 the form of stones and old tree roots, and the cost of 

 labour in the district. Having, however, ascertained 

 all this, a fair estimate may be formed by arranging a 

 price per rod, and ascertaining the number of rods in 

 an acre, which may be done as follows : 



Divide 29,040, the number of half yards linear at 

 I foot apart in an imperial statute acre, by the product 

 of the number of half yards in the rod of which the 

 number is required, multiplied by the given distances 

 apart in feet, and the quotient will be the number of 

 rods in a statute acre. Example. Required the 

 number of rods, of 5j yards, in an imperial acre, the 





