CHAP, in THE NATURE OF THE SOIL 21 



Allow the mud in the water you poured off to 

 settle, and then pour the water off. On examining 

 the mud you will find it to be a fine sticky clay. 

 "We have thus separated the soil roughly into 

 stones, remains of plants, sand, and clay. 



If we examine soils brought from different 

 places we shall find different proportions of sand 

 and clay, some containing a large quantity of clay 

 being called heavy clay soils, others containing a 

 large proportion of sand being called light sandy 

 soils. 1 



Sand alone forms a very loose, powdery soil, in 

 which the roots of the plants get little hold. Water 

 also passes through it quickly, as we can easily prove 

 by fashioning the sand into a hollow cup and pouring 

 water into it. 



Consequently sandy soil dries up quickly, 

 and the plants growing in it suffer from want of 

 water. 



Clay, on the contrary, will not allow water to 

 pass through it easily. If we model a little cup out 

 of clay, and fill it with water, it will remain there 

 and not drain through, as is the case with the sand. 

 A clay soil does not let the water pass freely through 

 it, so that it may dissolve food for the plant, and 

 supply the roots. 



A good soil, therefore, is a mixture of both these 

 bodies in suitable proportions. 



1 " Heavy " here means difficult to plough, " light " easy to 

 plough. Bulk for bulk, sandy soils weigh more than clay soils. 



