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Drains may be made in various ways, but it must be borne in 

 mind that no drain should be of less depth than will allow the 

 deepest culture without injury to itself. Where " blackboys " 

 (Xanthoreas] are plentiful, these may be used, and will last for a 



great number of years. A trench is dug to the required depth, 

 sufficiently wide to allow of two blackboy trunks being laid side by 

 side, the scales facing the way the water runs, with a few inches 

 of space between them, a third trunk is then placed on the top, as 

 shown in the illustration, and the trench tilled in, and the earth 

 well trodden down by \valking a heavy horse up and down it until 

 well solidified. 



A box drain may be made of slabs, split or sawn, or any waste 

 timber of any kind^ the two sides and top only being required, 

 unless the fall is very great, when it is advisable to have the bottom 

 in as well. Rubble drains, where stone is available, are cheaply 

 made, and very effective, the rubble being laid in the trench, as 

 shown in the illustration. 



Tile drains are really the best, and though expensive, and not 

 within the reach of everyone, are cheaper in the end, as, if care- 

 fully laid, their life should be at least half a century. 



The best shape for tiles is an oval, or elliptical bore, with one 

 or two flat outside bottoms. They should be made of well-ground 

 clay, well burnt, with not too much sand in their composition, 

 straight, smooth, and free from ragged ends. 



In making surface drains attention should be paid to the 

 character of the soil, in order to prevent scouring or the washing 

 away of the sides, as much as possible. The fall can be made 

 greater in stiff soils without this occurring, than in light soils. 



The advantages to be derived from draining may be summed 

 up as folio ,vs : Soils sweeten much more rapidly, and are con- 

 sequently sooner ready to throw a good crop ; they are more easily 

 and sooner \vorked ; lime and manures act better ; seed time and 



