CHAPTEK Vri 



THE SOIL AND THE SAP 



COMPOSITION OF THE SOIL— LIFE IN 

 THE SOIL— THE SAP 



The thirsty earth soaks up the rain, 

 And drinks and gapes for drink again ; 

 The plants suck in the earth, and are 

 With constant drinking fresh and fair; 

 The sea itself, which one would think 

 Should have but little need of drink, 

 Drinks twice ten thousand rivers up, 

 So fill'd that they o'erflow the cup. 

 The busy Sun (and one would guess 

 By 's drunken fiery face no less) 

 Drinks up the sea, and when h'as done, 

 The Moon and Stars drink up the Sun : 

 They drink and dance by their own light, 

 They drink and revel all the night. 



Abraham Cowley. 



Composition of the Soil. Leaf-mould 



IVlucH of the food of plants comes from the soil. Some soils 

 are homogeneous, that is to say, they consist of a series of 

 particles of the same or nearly the same chemical composition. 

 The sands of sea-beaches and of deserts and the coarse 

 silts of rivers and fresh-water lakes are for the most part 

 composed of nearly pure silica, but the finer silts and the 

 clays contain a larger proportion of muddy material, which is 

 essentially aluminium silicate, mixed with a variable amount 

 of other substances, especially iron oxides, in an extremely 

 fine state of division. The coarser-grained sands absorb water 

 and retain it between their constituent particles, but more 

 is absorbed by the finer silts and clays, which swell up when 

 water is added and contract when it is removed. When moist 

 these clays are sticky and can be easily moulded. Sand, on 

 the other hand, has a lesser power of absorbing and retaining 

 water, dries up quickly, and does not become sticky or form 

 hard nodules or clods. Neither afford good land for phuit 



