See — Temperature of the Sun and Ages of Stars and Nebulae. 45 



varies according to the taste of the investigator, but we 

 believe it is generally allowed that speculative inquiries 

 founded on mechanical laws are essential to the development 

 of Physical Science, and hence have not hesitated to apply 

 the mechanical theory of heat to some of the most interesting 

 phenomena of the heavens. 



Issued February 5, 1900. 



