40 AGRICULTURE. 



to get the water out and to let the air in. Then thorough 

 working should follow. The soil is plowed up in ridges in the 

 field, every furrow straight and clean cut, glistening in the sun 

 like metal in many places. But when the frost has torn it to 

 pieces during the winter, we find a great improvement in the 

 texture of it in the spring. The good effects of plowing 

 and harrowing will not appear on most clay soils unless the 

 land is first thoroughly drained. Drain the soil and let the air 

 work for you, breaking up the coarse particles in winter and 

 working over the particles in summer into soluble form for 

 plant food. Perhaps you do not realize how much of the soil 

 is still rocky and needs to be worked over. 



Take a deep bottle of clear water, and drop a handful of soil into it ; 

 shake it up a little, then take a small stick and slowly stir it. The heaviest 

 pieces will settle at the bottom, the smaller above, and the lightest on top. 

 Notice, now, how much coarse, stony material there is in this soil. 



Place a little sand, clay, or loam soil under a good magni- 

 fying glass, such as is used for examining grain. The soil looks 

 like a pile of small stones. And that is just what it is a mix- 

 ture of fine stones with vegetable matter or humus in it. These 

 small pieces of stone came from the great masses of rock on 

 the hillside. How did they come to be so broken up and 

 worked over ? The air got at them, and the dews, and the 

 rain, and the frost. Then if we open up the under-soil by 

 under-drainage, and thoroughly open up the surface soil by 

 tillage and cultivation, the air and the rain and the dew and 

 the frost will go on working over these fine stony particles, 

 forming soluble matter that can go in through the roots and 

 feed the plant. 



Thorough drainage and thorough tillage these are the two 

 main points in improving all soils. They are even more im- 

 portant than manuring. This word manure is the same as 

 manoeuvre, which means to "work by hand;" the draining of 

 the soil and the tilling are means of fertilizing or manuring. 



