UNDER THE MAPLES 



ing about the sky, going through various intricate 

 movements, with the precision of dancers in a 

 ballroom quadrille. No sign, no signal, no guid- 

 ance whatever. Let a body of men try it under 

 the same conditions, and behold the confusion, and 

 the tumbling over one another! At one moment 

 the birds would wheel so as to bring their backs 

 in shadow, and then would flash out the white of 

 their breasts and under parts. It was like the open- 

 ing and shutting of a giant hand, or the alternate 

 rapid darkening and brightening of the sail of a 

 tacking ice-boat. This is the spirit of the flock. 

 When a hawk pursues a bird, the birds tack and 

 turn as if linked together. When one robin dashes 

 off in hot pursuit of another, behold how their 

 movements exactly coincide! The hawk-hunted 

 bird often escapes by reaching the cover of 

 a tree or a bush, but not by dodging its pur- 

 suer, as a rabbit or a squirrel will dodge a dog. 

 Schools of fish act with the same machine-like 

 unity. 



In the South, I have seen a large area of water, 

 acres in extent, uniformly agitated by a school of 

 mullets apparently feeding upon some infusoria on 

 the surface, and then instantly, as if upon a given 

 signal, the fish would dive and the rippling cease. 

 It showed a unity of action as of ten thousand 

 spindles controlled by electricity. 



How quickly the emotion of fear is communi- 



154 



