IKTRODOCTION. 
Ixvii 
Little anatomical knowledge is required to convince iis of the truth of this 
remark ; and no great power of argumentation is necessary to demonstrate 
the absurdity of the belief, that a bird so lender, which cannot bear the 
inclemency of a cold vernal season, should become, at the approach of 
winter, so hardy an animal as to be capable of sustaining life in a dense, 
frigid element, where every other land bird, formed internally like itself, 
would meet immediate death; and should undergo a metamorphosis more 
strange and unnatural than any of the poetic fictions of Ovid, or the 
fabulous tales of the Proteus-like divinities of Homer. ” If all the Swal- 
lows and Martins plunged into a watery abode, to remain torpid throughout 
the winter, they would necessarily be often discovered m multitudes by 
some of those, who, from pleasure, or in their avocations, are frequently 
engaged on the streams. Though the bottoms of our rivers are continually 
disturbed by various instruments, what man, in Britain, ever saw the 
fisherman bring up Swallows in his dredge, or in his net, or on his spear ? 
The currents of many of our rivulets and streams are often turned ; and 
yet, in our history, there is not one well-substantiated fact of the discovery 
of Swallows at their bottoms ; wdiich must have been the case, had they 
constantly immersed themselves at the approach of winter. But their 
manners and their actions prove the reverse. If they reposed in neigh- 
bouring ponds and rivers, we may fairly demand of the advocates for sub- 
mersion, why do they, at the time of their departure, aseend to such 
towering heights in the air, that the eye can no longer trace their flight 
” It would be presumptuous to assert, that no Swallows have been found in a state of sub- 
mersion. Many names, venerable as naturalists, record it as a fact ; such facts, we believe to be 
very rare, and they merely prove a discovery in a few solitary instances, without accounting for 
the manner of their immersion^ or the time of their continuance in the stream. In our country such 
assertions carry doubt on the face of them, as the seasons in which they are supposed to have 
been discovered immerging into, or arising from, the stream, corresponds with the periods at 
which the Swallow retires to low, warm vallies, or marshy places, abounding with insects ; and 
there it might be chilled by the coldness of the atmosphere, sink entangled among the rushes, and, 
when discovered, give birth to intentional submersion. 
K 2 
