HOUSE-MARTINS. 
229 
Besides, it retires to rest for every shower ; and does not move 
at all in wet days. 
When one reflects on the state of this strange being, it is a 
matter of wonder to find that Providence should bestow such a 
profusion of days, such a seeming waste of longevity, on a rep- 
tile that appears to relish it so little as to squander more than 
two thirds of its existence in a joyless stupor, and be lost to all 
sensation for months together in the profoundest of slumbers. 
While I was writing this letter, a moist and w,arm afternoon, 
with the thermometer at 50, brought forth troops of shell-snails ; 
and, at the same juncture, the tortoise heaved up the mould and 
put out its head ; and the next morning came forth, as it were 
raised from the dead ; and walked about till four in the after- 
noon. This was a curious coincidence ! a very amusing occur- 
rence ! to see such a similarity of feelings between the two 
<pef)€oiKoil for so the Greeks call both the shell-snail and the 
tortoise. 
Summer birds are, this cold and backward spring, unusually 
late : I have seen but one swallow yet. This conformity with 
the weather convinces me more and more that they sleep in the 
winter. 
LETTER LI. To the Hon. DAINES BARRINGTON. 
Selborne, Sept. 3, 1781. 
I HAVE now read your miscellanies through with much care and 
satisfaction; and am to return you my best thanks for the 
honourable mention made in them of me as a naturaUst, which 
I wish I may deserve. 
In some former letters I expressed my suspicions that many 
of the house-martins do not depart in the winter far from this 
village. I therefore determined to make some search about the 
south- east end of the hill, where I imagined they might slumber 
out the uncomfortable months of winter. But supposing that 
the examination would be made to the best advantage in the 
spring, and observing that no martins had appeared by the 11th 
of April last ; on that day I employed some men to explore the 
shrubs and cavities of the suspected spot. The persons took 
pains, but without any success ; however, a remarkable incident 
occurred in the midst of our pursuit — ^while the labourers were 
