SOCIETY OF CENTRAL ILLINOIS. 279 



water like a spono^e, always moist, yet never wet. In these soils 

 plant food is held in solution ready for use. In the heavy clay or 

 alum soils water is held in such (piantities that it drowns rather 

 than nourishes. For surface-jjjrowiug" crops, surface drainage would 

 proljably be sutticient. For the grasses, especially clover or grains, 

 wheat, rye and oats, surface drainage with deep subsoiling would be 

 sutficieut to prevent suliseqnent ]iacking of the heavy subsoils, so as 

 to render them impervious to water. I'ulveri/ed lime-rock, sand, 

 ashes, gypsum or plaster, would be very valuable. Subsoiling to 

 great de[)ths will probably or eventually be the method adopted for 

 drainage, because it does not carry the water entirely away, nor al- 

 low it to be removed far enough to interfere with perfect plant 

 growth. When needed by extreme drouth it may be drawn by 

 cajiillary attraction back where it is needed and can be used. The 

 tilth and venom sjjoken of by the old writer as being contained in 

 water is all in the imagination. It is simply the plant's food, only 

 it must be placed where the plant can use it, that is, combined with 

 tlie jtroper degree of warmth and moisture, always bearing in mind 

 that much nu)isture requires much warmth, and that when we have 

 excessive warmth we require much moisture. 



In the tropics rain must fall almost daily, or the rapid evapora- 

 tion would soon l)e death to vegetation. ]\Iillions of acres of semi- 

 tro])ic California and Arizona, now called desert, would be a paradise 

 with the requisite rainfall. The drainage question is, no doubt, en- 

 titled to much consideration, both as an economic and sanitary 

 measure, but like many other topics, may become a hobby — run into 

 the ground— or at least overdone. A\'hile one system would do here, 

 it would be folly to apply it in another locality. Alluvial swamp 

 lands mav only require surface drainage, while lands with a sandy 

 or gravelly suljsoil, even where entirely level, would require no drain- 

 age at all. Those with impermeable hard pan would not be bejie- 

 tited by underdraining, because the water could not be drawn off 

 that way. Such lands would surely be injured by surface drainage 

 by allowing the soil to Ijecome baked and impenetrable. So it seems 

 that the remedy is to break it and keej) it porous by vegetable loam, 

 or substances without cohesive properties. 



T do not remember to have seen gravel south of the Cumber- 

 land Mountains; these, of course, are naturally well drained, even 

 where the surface is not rolling. In Louisiana and other Gulf States, 

 wherever drainage is at all practicable, it would be at the surface. 

 Coming nearer home, taking the Northern Middle Statos. more 

 especially Illinois and Missouri, we find an impermealde hard })an or 

 subsoil a few inches below the surface that holds water like cement, 

 when the hog wallow will hold water all summer. It would hardly 

 seem reasonable that a tile drain below the frost line at intervals of 

 100 feet or 100 yards would be of much practicable use exce|it to 

 draw off the surface or all above the hard pan, leaving the surface 



