102 Bureau of Farmers' Institutes. 



how much good it would do to land, and when I commenced dig- 

 ging a ditch through some blue clay, I said: " I don't see how it is 

 possible for the water to get through that. It is no use; it can't 

 draw from each side." But it did; but not until the ground had 

 once been frozen, and after it had been frozen twice, it did still 

 better. I looked at it like this, that the land is not so impervious 

 but that it gets full of water, and when it freezes it expands. It 

 commences to thaw out from below, making little channels 

 through the clay, and the clay being released, it doesn't pack 

 down so solid as it did before, so it is much better each year. 



Q. — Do you understand that the soil thaws out from under- 

 neath? 



The Chairman. — Yes, sir. 



Mr. Nicolai.^ — It thaws out from both sides. But I will give 

 another explanation in regard to loosening the clay soil. You all 

 know that angleworms will not work in water, but just as soon 

 as you dry out the water, and give them a chance, they will work 

 over the soil to the depth of the water, and in that way I think 

 the clay soil is helped very much. 



Mr. Wing.— I am glad to hear you speak of the angleworm, 

 because we have what we call exhausted soils in Ohio. They have 

 become tough and hard, and in those soils the angleworm helps 

 us after we have put on some manure. Of course, we do not 

 find them in the clay, but after the manure is put on, the humus 

 gets down, and they work through. 



Q. — Do you think there is any truth in the theory that high, 

 gravelly ground can be benefited by drainage in dry seasons? 



Mr. Nicolai. — It depends on what your high ground is. In land 

 where the surface soil is underlaid with sand or gravel, as natural 

 drainage, you cannot benefit by tiling, but heavy clay soil can be 

 benefited by drainage. It depends on where your land is located, 

 what the value of it is, etc.^ as to whether it is profitable. 



Mr. Wing. — Would you think it necessary to give a quarter 

 of an inch fall to the rod, if you don't have that much? 



