190 
NATURAL HISTORY 
The old tortoise, that I have mentioned in a former 
letter, still continues in this garden ; and retired under 
ground about the 20th of November, and came out again 
for one day on the 30th : it lies now buried in a wet 
swampy 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 XYIII. 
TO THE HONOURABLE DAINES BARRINGTON. 
Selborne, Jan. 29, 1774. 
HE house swallow, or chimney swallow, is, un- 
undoubtedly, the first comer of all the British 
Hirundines; and appears in general on or 
about the 13th of 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 hap- 
pened 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. 
* It has been remarked by the Hon. and Rev. W. Herbert that it 
