44 
THE NATURAL HISTORY 
[LETT. 
respect to birds that settled on their rigging during their voyage 
up or down the Channel. What Hasselquist says on that subject 
is remarkable : there were little short-winged birds frequently 
coming on board his ship all the way from our Channel quite 
up to the Levant, especially before squally weather. 
What you suggest with regard to Spain is highly probable. 
The winters of Andalusia are so mild, that, in all likelihood, the 
soft-billed birds that leave us at that season, may find insects 
sufficient to support them there. 
Some young men, possessed of fortune, health, and leisure, 
should make an autumnal voyage into that kingdom ; and should 
spend a year there, investigating the natural history of that vast 
country. Mr. Willughby passed through that kingdom on such 
an errand ; but he seems to have skirted along in a superficial 
manner and an ill-humour, being much disgusted at the rude 
dissolute manners of the people. 
I have no friend left now at Sunbury to apply to about the 
swallows roosting on the aits of the Thames : nor can I hear 
any more about those birds which I suspected were Meruhe 
torqiiatm. 
As to the small mice, I have further to remark, that though 
they hang their nests for breeding up amidst the straws of the 
standing corn, above the ground ; yet I find that, in the winter, 
they burrow deep in the earth, and make warm beds of grass : 
but their grand rendezvous seems to be in corn -ricks, into which 
they are carried at harvest. A neighbour housed an oat-rick 
lately, under the thatch of which were assembled near an hundred, 
most of which were taken ; and some I saw. 1 measured them, 
and found that from nose to tail, they were just two inches and 
a quarter, and their tails just two inches long. Two of them, in 
a scale, weighed down just one copper halfpenny, which is about 
the third of an ounce avoirdupois : so that I suppose they are 
the smallest quadrupeds in this island. A full grown Mus me- 
dius domesticiis weighs, T find, one ounce lumping weight, which 
is more than six times as much as the mouse above ; and mea- 
sures from nose to rump four inches and a quarter, and the same 
in its tail. We have had a very severe frost and deep snow this 
month. My thermometer was one day fourteen degrees and a 
