THE PASSING OF THE BIRDS. 193 
discovered all at once that there were none to 
be found. After the first of July I neither 
saw nor heard a cuckoo of either species! 
Had they moved away? I do not know; 
but the case may be taken as an extreme 
illustration of the uncertainty attaching to 
the late-summer doings of birds in general. 
Every student must have had experiences 
of a sort to make him slow to dogmatize 
when such points are in question. Through- 
out May and June, for example, he has 
heard and seen wood thrushes in a certain 
grove. After that, for a whole month, he 
hears and sees nothing, though he is fre- 
quently there. The thrushes have gone? 
So it would seem. But then, suddenly, 
they are singing again in the very same 
trees, and he is forced to conclude that they 
have not been away, but during their period 
of midsummer silence have eluded his no- 
tice. On the whole, therefore, after mak- 
ing allowance for particular cases in which 
we may have more precise information, it 
would be hard, I think, to say just when 
our nocturnal travelers set out on their 
long journey. As the poet prayed Life to 
do, — 
