16 THE WORLD IN WHICH WE LIVE 



about it some of her garment. Moss and lichen grow 

 upon it and finally cover it up, so that after years and 

 years it makes a long, moss-covered mound upon the 

 forest floor. If woods are cut down trees will begin 

 to grow again to take the places of the others. There 

 will be another forest there in time unless the stumps 

 of the old trees are destroyed and the land is culti- 

 vated. 



Nature never gets discouraged. She works over 

 and over again, so patiently, to cover the bare spaces. 

 If it is too bare or too dry for one plant to grow 

 she tries another and another. If an oak tree does 

 not like to grow on sandy soil, pine trees do; and little 

 birch trees will begin to grow on a gravel bank that 

 almost everything else seems to shun. 



Even the sand hills back from the seashore are 

 looked after. The wind likes to play with the sand 

 on these hills, and blows it around in shifting masses. 

 So nature plants a kind of grass there that has long, 

 creeping roots. These roots grow so long, and cross 

 and recross among themselves so often, that they 

 bind the sand compactly and the wind can blow only 

 a little off the top. 



You know how the rough old ocean plays with the 

 sand and pebbles on the beach and how the waves 

 move them about. But underneath the water, 

 where the waves are more quiet, the rocks are cov- 

 ered with seaweed. Long, slender masses wave to 

 and fro as the tide comes in or goes out. Under- 

 neath the seaweed are sea mosses of wonderful colors 

 and shapes, so fine and delicate that they must be 

 floated in water to be seen. The deeper the water is, 



