NATURAL HISTORY OF SELBORNE. 161 



border under a wall facing to the south, and is enveloped at 

 present in mud and mire ! 



Here is a large rookery round this house, the inhabitants 

 of which seem to get their livelihood very easily, for they 

 spend the greatest part of the day on their nest-trees when 

 the weather is mild. These rooks retire every evening all 

 the winter from this rookery, where they only call by the 

 way, as they are going to roost in deep woods : at the 

 dawn of day they always revisit their nest-trees, and are 

 preceded a few minutes by a flight of daws, that act, as 

 it were, as their harbingers. 



LETTER XVIII. 



SELBOBNE, Jan. 29th, 1774. 



THE house-swallow, or chimney-swallow, is undoubtedly the 

 first comer of all the British hirundines, and appears in 

 general on or about 13th April, as I have remarked from 

 many years' observation. Not but now and then a straggler 

 is seen much earlier ; and, in particular, when I was a boy 

 I observed a swallow for a whole day together on a sunny 

 warm Shrove Tuesday, which day could not fall out later 

 than the middle of March, and often happened early in 

 February. 



It is worth remarking that these birds are seen first 

 about lakes and mill-ponds ; and it is also very particular, 

 that if these early visitors happen to find frost and snow, as 

 was the case of the two dreadful springs of 1770 and 1771, 

 they immediately withdraw for a time a circumstance this 



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