OBSERVATIONS ON BIRDS. 



previous, they exercise their voices all together in a 

 very peculiar way, different from at other times, 

 producing a deep hollow sound that may be heard 

 to a considerable distance ; and it is a quarter of an 

 hour or twenty minutes before they are hushed for 

 the night. 



Late in the autumn, if the afternoons are cold and 

 frosty, and also often during winter, they may be 

 observed sitting in a sullen way, in immense clusters, 

 at the tops of the trees near adjoining the rookery, 

 which are blackened with their numbers, for an hour 

 or two before roosting : at such times they are quite 

 silent, and hardly noticed by persons passing, till 

 they all suddenly take wing, frightened at his 

 approach. But, if the weather be mild and open, 

 they keep flying about at the decline of day in 

 immense multitudes, high in the air, with an inces- 

 sant cawing, till the increasing darkness obliges them 

 to retire for the night. 



Rooks appear to be very restless at times in the 

 dead of the night, and to wake much ; for often at 

 10 and 11 p. m. (and this in winter as well as sum- 

 mer) I hear a squabbling and cawing on the nest- 

 trees near my room-window. They are early risers 

 too, and at all seasons leave their roosting-places 

 half an hour or more before sunrise. 



Jan. 16, 1830. Rooks up this morning at half 

 past seven exactly. N.B. Sky much overcast, with 



