STUDIES IN NATURE 



solving away of many different sorts of things, 

 it follows that there are a great many different 

 kinds of matter in it. Some of them are of 

 more use than others to the vegetable world ; 

 hence we hear fanners and gardeners speaking 

 of rich and poor soils, of hot and cold soils, and 

 we begin to ask what is the difference between 

 them. Besides the particles oi rock or mineral 

 matter in soil, there is, as we said, a large amount 

 of kumus, or decaying animal and vegetable 

 matter, which is particularly useful in binding 

 together the tiny particles, in collecting and 

 keeping the moisture, and in breaking up the 

 soil so that air and heat can enter into it. Sand 

 is an example of soil without kumus ; few things 

 can grow upon it, water runs quickly through it, 

 and its surface is alternately very hot and very 

 cold. But sand, when properly mixed with 

 decaying animal and vegetable matter, such as 

 farm-yard or stable manure, and well supplied 

 with water, will make an excellent soil, giving 

 fine crops, and well repaying all the trouble 

 which has been taken with it Dust, as we 

 know, is another form of soil which has lost its 

 moisture, and therefore its power of cohesion or 

 of sticking together! It can be lifted off the 

 surface of the earth and blown about by the 

 wind, and in towns we have to use watering- 

 carts to moisten the surface of the roads and 

 keep the dust from troubling us. 



The soil often varies in colour and quality 



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