VEGETABLE MOULD OF THE FOREST FLOOR. 145 



till recently the fashion to suppose that the earth's 

 age was to be counted in years. 



The accumulations of uncounted ages have thus grad- 

 ually carpeted the surface of the earth over thousands 

 of square miles, with a covering of vegetable mould, 

 often many feet in thickness; indeed when in the State 

 of Tennessee, we were assured that in some of the 

 bottoms near the Mississippi, this had actually been 

 found to consist of as much as fourteen feet deep of 

 solid leaf mould and other decayed vegetable matter. 



It is curious to observe some of the prostrate trunks 

 of these great trees, wich may be seen in numbers, 

 in every stage of decay. Some have recently fallen, 

 and their bleaching stems still form the finest kind of 

 seasoned timber. Others are overgrown with a close 

 covering of lichens, mosses, and ferns, marking the 

 progress of decay; and though the outward form con- 

 tinues in many instances to be preserved with little 

 change, the pressure of a human foot, of a man climber- 

 ing across, is occasionally enough to cause the giant 

 limbs of the defunct forest monarch to crush and crumble 

 into dust. No easy task it is sometimes to make one's 

 way across some of these great trunks, whose diame- 

 ter is often higher than a man's head. Then again 

 we come across others, where some great tree has 

 long since fallen, which has perhaps mouldered so 

 completely into decay, that a low, soft, moss-grown 

 ridge, like a long sepulchral mound, is all that remains 

 to attest the fact of its former existence. Here the 

 parent stem has actually returned to earth, and is in 

 a condition to form the cradle of new forms of life. 



This adaptation of decaying substances to form the 

 support of future rotations of living organisms is surely 



VOL. II. 10 



