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to answer. We do not know why the fire of the volcano and 
the rending of the earthquake should become locally extinct 
at different geological periods, or why the centres of volcanic 
eruption should vary ; but we know that they have formerly 
done so, and we do not doubt that they will thus vary again. 
The volcano and the earthquake are some of the principal 
means which the great Creator employs for the construc- 
tion and the adaptation of the planet on which we live; but 
when their forces are to be employed, or where, does not lie at 
present within the reach of man’s philosophy. 
