THIEVES OF THE NIGHT 



its eyes too are very big, looking, when it is 

 nervous, as if they would jump out of its head ; 

 besides which it is a slimmer, more mouse-like 

 creature than the common brown rat, and as 

 a rule is much smaller. Some people think that 

 the tame black-and-white rats that are kept 

 in cages belong to this kind, but I believe it is 

 never so, and that pet rats are always of the 

 common species at any rate all the piebald 

 rats I have seen have been of the latter kind. 

 The tame black rats that I had were very 

 pretty, interesting creatures, the little ones 

 being especially dainty ; but I never looked at 

 them without thinking what a strange history 

 lay behind those elegant, mouse-like rats. 

 How once upon a time their ancestors had 

 lived out in the wild desert, far from men, 

 until some rat more go-ahead than its fellows 

 had found out what good things were to be 

 had by following the camps and hunting round 

 the dwelling-places of mankind, so that they 

 became pests that live only where there are 

 people, and have passed with human beings 

 froTi their home in Central Asia to the farther- 

 most corners of the world ; and how another 

 rat of the Eastern deserts, our present common 

 rat, found out the same thing, and not only 



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