PART VI. 

 INORGANIC EVOLUTION. 



CHAPTER I. 



CELESTIAL DISSOCIATION. 



The products of the dissociation of the heavy atoms such 

 as radium and uranium render the air a conductor of elec- 

 tricity and this conductivity, and hence the dissociation 

 which causes the conductivity, is measurable by the elec- 

 troscope. The electroscope is hundreds of thousands of 

 times more sensitive than the most refined type of spec- 

 troscope in existence. This, however, should not detract 

 from the admiration which is due to the spectroscope. In 

 the same measure that the electroscope exceeds in sensi- 

 tiveness the spectroscope so does the spectroscope exceed 

 any other known instrument for the detection and mensu- 

 ration of minute quantities of matter. Besides, the elec- 

 troscope is exceedingly limited in its application while the 

 range of the spectroscope is as wide as the universe. That 

 the spectroscope will detect the millionth of a milligram of 

 matter, and on that account has discovered new elements, 

 commands our admiration; but when we find, in addition, 

 that it will detect the nature of forms of matter billions of 

 miles away and, moreover, that it will measure the velocities 

 with which these forms of matter are moving, with an ab- 

 surdly small per cent, of possible error, we can easily ac- 

 quiesce in the statement that it is the greatest instrument 

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