102 THE WONDERFUL CENTURY. 



greater number that must escape observation, it is sup- 

 posed that the actual number may be several hundred 

 millions. Of course it is only by a kind of accident 

 that the orbit of our earth crosses any of these meteoric 

 streams, so that there are certainly a vast number, per- 

 haps thousands or even millions, of such streams in the 

 solar system, since some hundreds are either known or 

 suspected to cross our path. Taking into consideration 

 these numerous meteor-streams moving in elliptic orbits 

 round the sun, together with the vast number of stray 

 meteors, as it were, indicated by those that are seen 

 every day in the year and by the exceptionally large and 

 rare fireballs, we are led to the conclusion that the space 

 occupied by the solar system, instead of being almost 

 empty, as formerly supposed, is really full of solid bodies 

 varying in size from that of dust or sand-grains up to 

 huge masses a thousand times that of our earth. 



The eight major planets are so remote from each other 

 that, if we represent the solar system as an open plain 

 two and a half miles in diameter, our earth will in due 

 proportion be shown by a pea, liars by a large pin's 

 head, Jupiter by an orange, and Neptune on the extreme 

 outer edge by a largish plum. From any one of them 

 the nearest would be invisible to us unless brilliantly 

 illuminated, and however smooth and open was the 

 plain, we might walk across it again and again in every 

 direction, and with the exception of the two-foot ball in 

 the centre representing the sun, we should probably de- 

 clare it to be absolutely empty. Looking thus at the 

 solar system, the vast emptiness, the absurd dispropor- 

 tion of the sizes of the planets to the immense spaces 

 around and between them, was almost oppressive; and 



