TILLING AND DRAINING THE SOIL. 39 



a hot day, we sprinkle the floor with water. As this water 

 evaporates, or passes off into the air, the floor becomes cooler, 

 and that cools the air above it. We may look upon a 

 swampy field as a great room, the floor of which is the soil. 

 If the soil is kept wet, the floor of this field will be kept cold. 

 Water is not easily warmed up or heated. A dry soil, or a soil 

 well drained, is warmed up by the sun more easily than a wet, 

 undrained soil. 



If you place a cup (stoneware) of water, a cup of wet sand, and a cup of 

 dry sand on the top of a warm stove, you will find that the dry sand be- 

 comes hot much more rapidly than the wet sand, and the wet sand much 

 more rapidly than the water. 



Again, if you wish to heat a pan of water, or to boil the 

 kettle, you place it over the fire, not beside the stove, nor 

 under the stove. The sun is the fire that heats up the soil and 

 the water in it, and it is above, so that the effect of heating the 

 water in the soil is very small. 



We have, then, three reasons why the presence of too much 

 water in the soil keeps the soil cold. We must get the water 

 out of the soil by drainage, so that we can thoroughly work 

 the surface of the soil ; so that the air can get into the soil to 

 sweeten it and help the decay of the humus ; and, also, so that 

 the soil can become warmed up early in spring for the sprouting 

 of seeds and the early growth of the plant. 



All that has been said here in regard to humus, or mucky 

 soils, applies also to sandy, loam, and clay soils, except that 

 sandy soils are not so much in need of special drainage 

 in most cases they drain themselves. The clay soils, when 

 well drained, do not bake upon the surface as they dry out, 

 and they are much more easily worked. The stickiness of 

 clay can be somewhat overcome by the use of lime. 



If you shake up some clay in a lx>ttle of water, and then throw in some 

 finely powdered lime, you will ol>serve a peculiar efTect upon the fine clay 

 it will become flaky or coagulated and the water will clear up. 



The thorough drainage of clay soils, then, is most important 



