WATCHING ROOKS 273 



in the trees remain there as silent as ever, nor is there 

 any special note uttered by any one bird of the flock, 

 nor anything else whatever to suggest that any par- 

 ticular bird or birds is acting the part of sentinel." 

 There is certainly no sentinel in this case, and in 

 matters directly affecting their safety one might 

 suppose that rooks, as well as other birds and beasts, 

 would act in a uniform manner. This, however, we 

 can clearly see, that when there happen to be trees, 

 near where they are feeding, some of them will usually, 

 and quite naturally, be perched in them, and average 

 human observation and inference may have done the 

 rest. 



Rooks, I am inclined to think, are not birds that 

 give their conscience into keeping. Each one of them 

 is his own sentinel. 



