306 THE STRUCTURE AND LIFE OF BIRDS CHAP. 
another man with whom we are familiar is a difficult 
problem ; we are each of us so isolated from every one 
else. When it comes to reading the thoughts of a 
bird, we must expect sometimes to arrive at very 
wrong results. Poets in ancient times invariably 
represented the Nightingale as a melancholy bird who 
poured forth a dirge. They read their own thoughts 
into the bird’s song, like a German commentator 
who reads profundities into the simplest line of. 
Shakespeare. And then the legend of Philomela 
made permanent a notion which otherwise might 
have given place to a more natural one. In this case 
the modern view can hardly be wrong, that, though no 
doubt there is a strong admixture of other motives, the 
Nightingale sings to give vent to his exuberant spirits. 
There are some birds whose song, if it expresses any- 
thing at all, expresses the wildest jubilation. Such is 
the song of the Lark. The Robin, it is true, seems 
even in spring time to put into his note something 
of the melancholy of autumn. But what seems 
melancholy to us need not be so to him. The 
hideous cry of the Peacock is, no doubt, charming to 
himself and, very possibly, to the Pea-hen. 
Society has on many birds an exhilarating influence: 
Rooks when they come home for the night fly round 
and round, making a babel of cawing, before they 
settle down to rest. Mr. Hudson? describes several 
great flocks of Crested Screamers singing alternately 
—a splendid and orderly concert. Wild birds have 
superabundant health and spirits from the simple fact 
that illness nearly always means for them speedy 
1 Naturalist in La Plata, p. 227. 
