302 WILD TRAITS IN TAME ANIMALS. 



nothino- would so startle the world as an an- 

 nouncement that in an absolutely sterilised and 

 hermetically closed tube some exceedingly low 

 living organism had appeared spontaneously. 

 But we find that two hundred years ago learned 

 men accepted almost as a matter of course the 

 doctrine that many highly organised worms and 

 insects were bred spontaneously out of dirt. As 

 soon as students be^an to give attention to the 

 everyday phenomena round about them, it was 

 found that the world, instead of containing seven 

 wonders, contained seventy times seven ; and as 

 knowledge has increased these have multiplied 

 into innumerable myriads. 



Although the comparison may appear rather a 

 fanciful one, it may be said that the same change 

 has corne over natural phenomena (regarded from 

 the philosophic standpoint) as has come over 

 civilised society. Science is a great leveller. It 

 has pulled down mighty wonders from their seats 

 and has exalted facts of low degree. The old 

 oligarchy of marvels which was once supreme in 

 the realm of natural history, and whose claim to 

 prominence rested upon self-assertion or unstable 

 tradition, and was not broadly based on law, has 

 gone the way of many aristocracies whose tenure 



