1 ApRit, 1902.] QUEENSLAND AGRICULTURAL JOURNAL. 237 
Ting DRAINAGE. 
The cost of digging drains, whether you reckon your own time or the 
wages paid to the hired man or contractor, is a very large item in the operation 
of draining. Hence it is that tile draining is really less costly than any other 
style, the cost of the tiles being compensated for by the difference in the cost 
of digging the drains. 
The limit of efficient drainage in any soil is 4 feet deep and the drains 30 
feet apart, for if they are placed further apart there will be some land beyond 
the influence of the drain which is consequently undrained. «As a rule, they 
should be 3 feet deep and from 18 to 20 feet apart. Now about the size of the 
tiles: 2 inches in diameter is the smallest size that should be used under any 
conditions for lateral drains, and when they are of any length, say over 100 
yards, 3-inch tiles should be used, and for open soils 4-inch tiles are not too 
large. The size of tile for the main drain will depend upon the area to be 
drained, and will run to 4, 6, or 8 inches in diameter. 
