THE STORY OF THE NOVEMBER METEORS. 445 



version. If this be attained, and applied vigilantly and continuously, 

 there is, I have no doubt, far more probability of recovery from an 

 unfortunate inheritance than from an attack of ordinary disease. The 

 chief peril in the latter condition lies in the severity of the struggle, 

 the ground of safety in the former in its mild prolongation, whereby 

 the law of reversion can have unimpeded opportunity through the 

 long and steadfast application of favoring conditions to restore the 

 body to its pristine vigor. The thought may occur that not many 

 have the requisites alleged to be needful for the restoration of defec- 

 tive blood. Yet even this has an outcome not to be deplored,. High 

 intelligence, and a will subordinate to it, will survive ; while feeble 

 minds and groveling instincts will carry the blood on to overt disease, 

 to untimely death, and to extinction. 



THE STOKY OF THE NOVEMBER METEORS.* 



By G. JOHNSTONE STONEY, F. K. S. 



WHEN observers band together to watch every quarter of the 

 sky, and to keep on the lookout through the whole night, the 

 number of meteors that present themselves is very great. In this way 

 it has been ascertained that upward of thirty on the average, which 

 are conspicuous enough to be seen without instruments, come within 

 the view of the observers stationed at one locality. And it is com- 

 puted that telescopic meteors must be about forty or fifty times as 

 numerous as those visible to the naked eye. 



These results may be obtained from observations made at one 

 station ; but when concerted observations are carried on at different 

 stations several other facts of interest come to light. By simultaneous 

 observations at distant stations, it has been discovered that the height 

 of meteors above the surface of the earth usually ranges from one 

 hundred and twenty down to twenty miles, the average height being 

 about sixty miles ; that the direction of their flight is toward the earth, 

 either in a vertical or in a sloping direction ; and that their speed in 

 most cases lies between thirty and fifty miles a second. 



We thus arrive at the conclusion that visible meteors are phenomena 

 of our own atmosphere ; and as the atmosphere reaches a height, at 

 most, of one hundred and fifty miles, and is, therefore, but a thin film 

 over so vast a globe as the earth, it is obvious that the spectators at 

 any one place can see only a very small portion of the meteors which 

 dart about through all parts of this envelope. After making allow- 

 ance for this, we are forced to conclude that no fewer than 300,000,000 



* Lecture before the Royal Institution, February 14, 18*79. 



