A HISTORY OF SCIENCE 



Dr. Mayer himself hit upon what seemed a tenable 

 solution at the very outset. Starting from the ob- 

 served fact that myriads of tiny meteorites are hurled 

 into the earth's atmosphere daily, he argued that the 

 sun must receive these visitants in really enormous 

 quantities sufficient, probably, to maintain his tem- 

 perature at the observed limits. There was nothing 

 at all unreasonable about this assumption, for the 

 amount of energy in a swiftly moving body capable 

 of being transformed into heat if the body be arrested 

 is relatively enormous. Thus it is calculated that a 

 pound of coal dropped into the sun from the mathe- 

 matician's favorite starting-point, infinity, would pro- 

 duce some six thousand times the heat it could en- 

 gender if merely burned at the sun's surface. In other 

 words, if a little over two pounds of material from in- 

 finity were to fall into each square yard of the sun's 

 surface each hour, his observed heat would be account- 

 ed for; whereas almost seven tons per square yard of 

 stationary fuel would be required each hour to produce 

 the same effect. 



In view of the pelting which our little earth receives, 

 it seemed not an excessive requisition upon the meteoric 

 supply to suppose that the requisite amount of matter 

 may fall into the sun, and for a time this explanation of 

 his incandescence was pretty generally accepted. But 

 soon astronomers began to make calculations as to the 

 amount of matter which this assumption added to our 

 solar system, particularly as it aggregated near the sun 

 in the converging radii, and then it was clear that no 

 such mass of matter could be there without interfering 

 demonstrably with the observed course of the interior 



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