Preface 



photography follows the essay by Professor 

 Young.* 



All that the heavens declare is repeated by the 

 rocks as we listen to their story of evolution. In 

 a classic argument, here presented, Sir Charles 

 Lyell maintained that our planet has become 

 what it is by virtue of forces such as make the 

 world at sunset differ by a little from the earth 

 that faced the dawn. He showed that the hills 

 once called eternal are anything but changeless, 

 for their very height has made them the targets 

 of tempest, has delivered them to the dividing 

 axe of frost. A striking object lesson as to the 

 cumulative effect of agencies, each in itself 

 trivial enough, is the comparison of water courses, 

 /rom the runlet which succeeds a shower, to the 

 Mississippi, sweeping to the sea its spoil from the 

 hills and valleys of half a continent. Here the 

 teacher is one of the first geologists of the age, 

 Professor Shaler, of Harvard University. A 

 similar discourse, of equal pith, is contributed by 

 Professor Huxley, who shows us how the sea 

 carves and sculptures its margins, and scatters 

 on its floors the strata which shall duly emerge 

 to air and sunshine. The same great teacher 

 closes the volume with a chapter on earthquakes 

 and volcanoes, those mighty agents for the arrest 



* Should the reader be happily incited by these chapters 

 to some personal acquaintance with the heavens, he need 

 not await the possession of a telescope. Mr. Garrett P. Ser- 

 viss in his " Astronomy with an Opera Glass " shows how an 

 observer may not only begin but proceed far with that sim- 

 ple and inexpensive instrument. 

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