152 LIGHT SCIENCE FOR LEISURE HOURS. 



opposite the crossing places through which the earth 

 herself passes on August 11 and on November 13. 

 But we know now the precise form of each system, 

 and we find that the other crossing place of the 

 November system lies some nineteen times farther 

 from the sun than the earth's orbit, while the August 

 system also crosses the plane of the earth's orbit, much 

 farther away than the earth travels from the sun. In 

 other words, although rays from the sun towards the 

 earth on or about February 7, and again on or about 

 May 12, do undoubtedly fall upon the August and 

 November meteor systems, they so fall not on their 

 way to the earth, as Erman supposed, but long after 

 they have passed the earth. As I wrote in Knowledge 

 for May 26, 1882: 'To charge, then, the August or 

 the November systems with robbing our earth of a 

 portion of its supplies of solar heat is to act like the 

 wolf in the fable, who accused the lamb of troubling 

 the stream, though the stream flowed from the wolf 

 towards the lamb.' Our earth may intercept some of 

 the supplies of solar light and heat passing out towards 

 the November and August meteor systems, but 

 assuredly neither of these systems can cut off any of 

 the supplies sent out to the earth. 



It is noteworthy, indeed, and I think surprising, 

 how little the topography, so to speak, of the August 

 and November meteor system seems to be understood 

 even by authors who, though writing popularly, are 

 supposed yet to understand what they are writing 

 about, and in fact to have no other object in writing 



