216 BOARD OF AGRICULTURE. 



to show by pretty careful mathematics elsewhere — that it costs 

 twice as much to dig a drain of four feet as it does to dig one 

 of three feet, for the reason that you have to open your ditch 

 wider at the top, throw out more earth, lift it higher, and ordi- 

 narily it will be harder to move, and you work at a disadvan- 

 tage. Still I have practised, as far as I have been able, putting 

 my drains fully four feet deep ; and I have, in my Exeter farm, 

 found them wonderfully successful. Before I tried tiles, I tried 

 all sorts of things. I tried bushes, and loose stones, and flat 

 stones, and in all these ways I had good results temporarily. 

 For a while they would drain sufficiently, but in a few years 

 they would fail by getting filled up. 



Mr. Keyes. a single question further. How near together 

 should side drains be ? 



Mr. French. Of course I give nothing but an approximate 

 answer to such a question. From sixteen to sixty feet would be 

 given as the outside limits. In England, in clay lands — and 

 that means clay in England ; it does not mean what we call clay 

 around here sometimes ; it means blue clay, or brick clay — in 

 such lands they sometimes put their drains as near together as 

 sixteen feet. On ordinary loamy soil, or in peat swamps, I 

 think you may put your drains from thirty to forty feet apart, 

 and be pretty sure of good results if you get them four feet 

 deep. I tliink that is ordinarily near enough. I have put 

 drains in forty feet apart that have done excellently well. The 

 deeper they are, within reasonable limits, the further apart they 

 may be. In clay lands there is a singular effect produced by 

 drainage, which I have witnessed myself, and writers on the 

 subject speak of it. You may take clay land — brick clay — that 

 will hold water, and put drains into it four feet deep, and in 

 two years' time it will become full of cracks, so that the water 

 will pass readily down through it ; you will not find half an 

 inch square that has not a crack in it ; and this clay land 

 becomes open, friable, so that its character is entirely changed. 



The worst obstacle you will find will be from the drains filling 

 with what writers call " silt," by which they mean a very fine 

 sand — clay, so fine that it will pass almost anywhere where 

 water will pass. I think people who have failed (and I don't 

 think there are many,) in tile drainage, have failed by not being 

 careful enough in securing the joints or in selecting the tiles. 



