BAEN SWALLOW. 223 



may have been found in a hollow tree, and in great numbers too, is not 

 denied ; such being in some places of the country (as will be shown in 

 the history of that species), their actual places of rendezvous, on their 

 first arrival, and their common roosting place long after ; or that the 

 Bank Swallows, also, soon after their arrival, in the early part of spring, 

 may be 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 arbund 

 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 my- 

 self 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 communicated by Sir John 

 Trevelyn, Bart., to Mr. Bewick, the celebrated engraver in wood, will 

 be suflScient for our present purpose, and throw great light on this part 

 of the subject.* 



" Five or six of these birds were taken about the latter end of August, 

 1784, in a bat fowling net at night ; they were put separately into small 

 cages, and fed with Nightingale's food : in about a week or ten days 

 they took food of themselves ; they were then put all together into a 

 deep cage, four feet long, with gravel at the bottom ; a broad shallow 

 pan with water was placed in it, in which they sometimes washed them- 



* See Bewick's British Birds, vol. i., p. 254. 



