170 THE BIRDS OF SHERWOOD FOREST. 
our own district it is abundant ; but nowhere, I believe, 
does it equal in numbers either of the other hirundines. 
They are of social habit, delighting to hunt in company, 
generally in parties of from two to eight or ten pairs ; 
and few sights are more beautiful than to watch a flock 
as they dart past like an arrow, or wheel with impetuous 
flight round the church tower, squealing all the time as 
if in the very exuberance of unfettered liberty and joy ; 
and unfettered it truly is, for in the power, rapidity, and 
elegance of its ordinary flight, and its untiring activity, 
it has few rivals and still fewer equals. 
The swift’s period of residence with us is a very brief 
one, rarely exceeding two months and a half. No 
avant-courier precedes their arrivai, which is sudden 
and simultaneous; one day none are to be seen, and the 
next they are in full force, making the air ring with 
their shrill cry. Their departure is also equally sudden, 
though not always so simultaneous, as now and then you 
may meet with a pair detained, perhaps for a week or 
two after their friends have departed, by domestic cares. 
The first week in May is the usual time of their appear- 
ance; but in 1854 I remarked an exception to the 
general rule, a single bird making its appearance on the 
4th of April. This is the earliest date, and the 15th of 
May the latest, on which I have noted their arrival. 
Some writers say the swift sometimes lays three or 
four eggs, but I never met with more than two. The 
old ducal mansions in our neighbourhood are always 
tenanted by several pairs, and the roofs of old houses are 
also frequented, the birds gaining entrance under the 
pantiles. These last are the most favourite resorts of 
the house sparrow, whose nest, I believe, is very fre- 
quently made use of by the swift without the owner's 
