290 BIRD WATCHING 



motion does not, any more than the lesser ones, 

 spread itself through the packed community, but is 

 strictly isolated. How strange this seems ! A 

 parliament (though I heard no nonsense talked) of 

 lively, eminently gregarious birds, all of which are 

 noisy at one time or another, and from the thick of 

 them a storm of clamour bursts : would not one 

 think that the birds sitting cheek by jowl with the 

 stormers would storm too, and so ' pass it on ' ? 

 Why should there be a periphery, and what should 

 limit the chorus except the bound of the plantation 

 itself? Do crowds shout in patches? That the 

 clamour should cease, after a time, is, of course, natural, 

 but why, though it died along the road by which it 

 travelled, should it not keep travelling on, through 

 all the black, serried ranks? If rooks were influenced 

 only by the outward manifestations of each other's 

 emotions, one might, surely, expect this. But now, 

 if they were influenced more by the thought itself, 

 rapidly transmitted from one to another of them, then, 

 whenever this factor ceased, for whatever reason, to 

 act, the birds beyond the limits of its action might be 

 unaffected by the cries of those who had felt its in- 

 fluence, for they would have been accustomed to look 

 for a sign from within, and not from without. They 

 might then hear, on some occasions, without being 

 impelled, though on other occasions they might choose^ 

 to join. It may be difficult to realise such a psychical 

 state, but that does not, of itself, make the state im- 

 possible. Its possibility would depend upon the 

 reality or not of collective thinking, or thought-trans- 

 ference, and observation is (or should be) our only 

 means of deciding as to this. 



