96 THE CHEMISTRY OF CREATION. 



dropped by birds, fell upon the alluvium ; soon 

 they put forth roots and leaves and flourished in 

 great luxuriance, for this soil is very rich in the 

 mineral ingredients and metallic oxides which 

 plants require for their nutrition. More and 

 more plants tenanted the once bare and naked 

 surface, and it soon looked green and flourish- 

 ing. Grasses and herbs crowded upon it ; 

 and where but a short time before the turbid 

 waters of the river rolled down, now, in green 

 glory waved a number of humble plants, whose 

 vigour of growth sufficiently indicated how ac- 

 ceptable the situation they occupied was to 

 them. So it went on for a Spring, Summer, 

 and Autumn. But Winter came, and slew all 

 these, for they fell withered and dead, beneath 

 his icy touch, and showers of dead leaves, from 

 the forest on the hills hard by, covered them 

 over as in a tomb. As soon as they were dead, 

 the powers of chemistry began to act upon them. 

 Water and oxygen caused their dead parts to 

 rot or decompose, to become softened, reduced to 

 powder, and at length to become altered into that 

 very brown mould, which we now find on digging 

 into the surface. 



The layer thus formed was, of course, very 

 thin at first. But year after year, as it saw 

 fresh plants spring up, flourish, die, and decay, 

 added to its thickness ; and so in course of time 



