I IN STARRY REALMS. 



at a time now perhaps not far distant, to become of great 

 scientific interest. I propose to devote this and the few 

 following chapters to the more important relations of the 

 gun to the earth. I shall strive to illustrate the different 

 functions which the sun has to perform, and I shall point 

 out how it is that he is enabled to send down his benefits 

 upon the dwellers on this earth with a profuseness that 

 shows no signs of exhaustion. 



Let us begin by considering the extent to which we are 

 indebted to the sun for maintaining the earth in the same 

 orbit year after year. It would almost seem as if our 

 globe were always trying to escape from the thraldom of 

 the sun. If the sun were to withhold that attractive 

 power by which the earth is maintained in the course that 

 it at present follows, dire calamity must immediately result. 

 This globe of ours is hurrying along at a pace of eighteen 

 miles a second, and if the sun's attraction no longer re- 

 strained it the globe would not continue to revolve in a 

 circle, but would at once start off in a straight line on a 

 voyage through space. Every minute would take us more 

 than a thousand miles, and by the time a hundred days had 

 elapsed we should be twice as far from the sun as we are 

 at present. His light and his heat would be reduced to 

 one- fourth part of what we now enjoy. With every suc- 

 cessive minute the sun's influence would still further abate, 

 and it is almost needless to add that all known forms of 

 life would have to vanish from the globe. It is, therefore, 

 satisfactory to know that we possess sufficient grounds for 

 our belief that the sun's attraction will never decline from 

 what it is at this moment, and therefore that there is 

 no cause for apprehension that life may be chased from 



