ON THE INSTINCTS OF BIRDS. 145 
autumnal migration, is alone sufficient to establish 
the instinctiveness of that inclination which can thus 
overcome their parental affection—a feeling so ener- 
getic as frequently to counteract one of the most 
powerful laws of nature, self-preservation. No theory, 
in short, which is not founded on the opinion that 
birds of passage, in undertaking their annual jour- 
neys, are influenced by an instinctive desire to mi- 
grate, lable to be called into action by various 
exciting causes, can satisfactorily account for the 
remarkable phenomena which result from this perio- 
dical disposition to wander. 
The certainty with which the Carrier Pigeon directs 
its course towards its accustomed home from distant 
places where tt has never been before, after every 
precaution has been taken in its conveyance to pre- 
vent it from obtaining any knowledge of the way by 
observation, must, as well as the act of migration, to 
which it bears a striking resemblance, be hkewise 
attributed to instinct*. 
* Some birds, though not migratory, occasionally undertake 
long journeys, in which they cross extensive tracts of water. 
On the 16th of March, 1823, at noonday, my father saw, from 
the deck of the ‘ Vixen,’ steam-packet, bound for Holyhead, being 
then near mid-channel, about thirty Rooks winging their course 
towards the Irish coast, and, almost an hour after, five others 
were observed following in the same direction. The flight of 
these birds was low, silent, and direct; a steady breeze from the 
east was blowing at the time, and they passed within a short 
distance of the vessel. 
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