410 SKETCHES OF CREATION. 



solar energy. It is not an exhaustless resource, but it pro 

 longs materially the period of the sun s activity. Though 

 no pomet has been known to fall into the sun, it is now gen 

 erally admitted that cosmical matter is raining down upon 

 the sun from every direction. 



Besides the planetary and cometary bodies which re 

 volve about the sun, it is now demonstrated that the inter 

 planetary spaces are occupied by smaller masses of matter, 

 from the size of a meteorite to particles of cosmical dust. 

 These all are flowing about the sun in a circling stream, 

 but forever approaching nearer and nearer, until they are 

 gradually drawn into the solar fires. The showers of me 

 teoric hail which pelt our earth at certain periods of the 

 year are merely cosmical bodies that have been diverted 

 from their path by the proximity of the earth in certain 

 parts of her orbit. That faint cone of light which streams 

 upward from the setting or the rising sun, near the time 

 of the equinoxes, is but a zone of planetary dust illumina 

 ted by the sun s rays a shower of matter descending upon 

 the solar orb, and rendered visible to us, like the rain sent 

 down from a summer cloud and projected upon the clear 

 heavens beyond. 



Arrested motion becomes heat. The blacksmith s ham 

 mer warms the cold iron. A meteorite falling through the 

 earth s atmosphere develops so much friction as to gener 

 ate heat sufficient to dissipate the body into vapor. One 

 of these cosmical bodies falling upon the sun must, by 

 the concussion, produce about 7000 times as much heat is 

 would be generated by an equal mass of coal. It is thus 

 that the enormously high temperature of our sun is main 

 tained. 



But the very mention of this source of recuperation of 

 exhausted solar energy suggests a limit to the process. 

 For how many ages can the cosmical matter within the 



