THE ROOTS OF THE FOREST TREES. 57 



crow's quill ; but, on digging down a foot or eighteen inches 

 beneath, the root enlarges to a tuber often as big as the head of 

 a young child, which, on the rind being removed, is found to 

 be a mass of cellular tissue filled with fluid much like that in a 

 yonng turnip. Owing to the depth beneath the surface at which 

 it is found, it is generally deliciously cool and refreshing. Thus, 

 even in the desert, the bounty of the Almighty not only disposes 

 the organisation of the plants so as best to secure their own 

 existence, but also raises them as sustenance for man ; for with- 

 out their succulent roots these barren and poverty-stricken lands 

 would be all but uninhabitable. 



The creeping plants of the desert serve, moreover, a double 

 purpose ; for besides their use as food, they fix, by means of the 

 extensive ramifications of their roots, the constantly shifting 

 sands, thus rendering services similar to those of the sand-reed 

 on the dunes along the sandy coasts of the North Sea. 



Those trees which naturally grow in situations where they are 

 exposed to all the fury of the winds are invariably provided with 

 roots of a corresponding power of resistance. On the brow of 

 the northern hills the centenary fir defies the wintry blast; his 

 strong vertical root dives deep into the crevices of the soil, or 

 embraces the rock with sinewy arms. The proud columnar 

 trunk, with its vast crown of foliage, rocks to and fro in the 

 storm, but withstands its utmost efforts. The noble oak also is a 

 match for the most terrific tempests, until the decay of old age 

 has eaten its way into the trunk or roots, and undermined the 

 venerable giant's strength. 



The large high-stemmed palms penetrate, while germinating, 

 to a depth of three feet before the roots begin to spread, while 

 the palms of lower growth, that do not require so firm an 

 anchorage in the soil, send forth their roots near to the surface. 

 When we consider that the cocoa-nut tree, which bears its mag- 

 nificent tuft of colossal fronds and heavy racemes on the top of 

 a slender shaft one hundred feet high, thrives best on the sea- 

 shore, where the tropical hurricane has full play for its utmost 

 fury, we can form some idea of the admirable foresight which 

 gave its roots the necessary strength to resist the leverage of so 

 prodigious a weight. 



Trees with more superficial roots, such as the common pine, 

 which scarcely penetrates into the soil to a greater depth than 



