130 
BARN SWALLOW. 
chilled by the cold mornings which we frequently experience 
at that season, and be found in this state in their holes, I would 
as little dispute ; but that either the one or the other has ever 
been found, in the midst of winter, in a state of torpidity , I do 
not — cannot believe. Millions of trees, of all dimensions, are 
cut down every fall and winter of this country, where, in their 
proper season, Swallows swarm around us. Is it, therefore, 
in the least probable that we should, only once or twice in an 
age, have no other evidence than one or two solitary and very 
suspicious reports of a Mr Somebody having made a discovery 
of this kind ? If caves were their places of winter retreat, 
perhaps no country on earth could supply them with a greater 
choice. I have myself explored many of these, in various 
parts of the United States, both in winter and in spring, 
particularly in that singular tract of country in Kentucky, 
called the Barrens, where some of these subterraneous caverns 
are several miles in length, lofty and capacious, and pass under 
a large and deep river — have conversed with the saltpetre 
workers by whom they are tenanted ; but never heard or met 
with one instance of a Swallow having been found there in 
winter. These people treated such reports with ridicule. 
It is to be regretted that a greater number of experiments 
have not been made, by keeping live Swallows through the 
winter, to convince these believers in the torpidity of birds of 
their mistake. That class of cold-blooded animals which are 
known to become torpid during winter, and of which hundreds 
and thousands are found every season, are subject to the same 
when kept in a suitable room for experiment. How is it with 
the Swallows in this respect? Much powerful testimony 
might be produced on this point : the following experiments, 
recently made by Mr James Pearson of London, and com- 
municated by Sir John Trevelyn, Bart, to Mr Bewick, the 
celebrated engraver in wood, will be sufficient for our present 
purpose, and throw great light on this part of the subject.* 
* See Bewick’s British Birds, vol i. p. 254. 
