UNDER THE APPLE-TREES 



shore in Alaskan waters, or when the campers in the 

 forest heard a tree fall in the stillness of the night. 

 In both cases the tree's hour had come; the balance 

 of forces was suddenly broken by the yielding of 

 some small particle in the woody tissues of the tree, 

 and down it came. In all such cases there must be 

 a moment of time when the upholding and down- 

 pulling forces are just balanced; then the yielding 

 of one grain more gives the victory to gravity. The 

 slow minute changes in the tree, and in the stone 

 wall, that precede their downfall, we do not see or 

 hear; the sudden culmination and collapse alone 

 arrest our attention. An earthquake is doubtless 

 the result of the sudden release of forces that have 

 been in stress and strain for years or ages; some 

 point at last gives way, and the earth trembles or 

 the mountains fall. 



It is the slow insensible changes in the equipoise 

 of the elements about us that, in the course of long 

 periods of time, put a new face upon the aspect 

 of the earth. Rapid and noisy changes over large 

 areas, which may have occurred during the geologic 

 ages, we do not now see except in the case of an 

 earthquake. It is the ceaseless activity, both chem- 

 ical and physical, in the bodies about us, of which 

 we take no note, that transforms the world. Atom by 

 atom the face of the immobile rocks changes. The 

 terrible demonstrative forces, such as electric dis- 

 charges during a storm, which seem competent to 



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