SHOWERS OF SHOOTING STARS. 239 



doubt they vary in size, but they are probably not larger 

 than the pebbles on an ordinary gravel walk, and possibly 

 much less. The shape in which this host is marshalled is 

 remarkable. It is a long column, of which the width is 

 small in comparison with the length. The dimension of 

 this celestial host is indeed portentous. We sometimes 

 judge of the length of a procession of carriages by stating 

 how long they take to pass a certain point. We can 

 express the length of this great procession of meteors by 

 saying that, if we were to stand still and watch them file 

 past, not less than a year must elapse before the mighty 

 host would have passed by. This is, of course, an imper- 

 fect conception until we realise the velocity with which 

 the meteoric procession is moving. Their speed is cer- 

 tainly short of that which flashes through the electric 

 wire, but none the less does it utterly transcend any speed 

 which we can produce mechanically. The velocity of the 

 Leonids sometimes exceeds twenty-six miles a second, a 

 pace which is more than fifteen hundred times swifter 

 than the swiftest express train. 



The width of this column as it passes along is prodi- 

 gious when measured by ordinary standards. A cord 

 that would go four times round our earth would barely 

 suffice to stretch across the meteoric current, which is 

 100,000 miles from side to side. But this dimension 

 shrinks into insignificance when compared with the length. 

 To realise the true shape of the mighty host, we may use 

 Mr. Stoney's admirable illustration. He says, take a 

 piece of the finest sewing silk, about a foot and a half 

 long. Then imagine the silk to be magnified, while still 

 preserving its proportions, until its width is about one 



