attempt to shake the firmly settled fancy. The
eminent professor has it all his own way, and
his pupils earnestly desire that his extravagance,
thus triumphantly vindicated, may be
immortalised.
A theory, which is little less physically
impossible than that of Dr. Morton, has long
found acceptance with dispassionate and scientific
observers, and even now is not so thoroughly
exploded but that it exercises influence over
the minds of some. The fancy is, that in winter,
some birds, at all events the swallow tribe,
retire to the bottoms of lakes and rivers, and
pass the dead months in a torpid condition
under water. Olaus Magnus was one of the
earliest, if not the first to adopt this strange
notion. He was followed by Etmüller, and
afterwards by Derham, who quotes in confirmation
of the theory a communication made to the
Royal Society in 1712, "from Dr. Colas, a person
very curious in these matters. He, speaking
of their way of fishing in the northern parts,
by breaking holes, and drawing their nets under
the ice, saith, that he saw sixteen swallows so
drawn out of the lake of Samrodt, and about
thirty out of the king's great pond in Roseneilen;
and that at Schlebittin, near an house of
the Earl of Dohna, he saw two swallows, just
come out of the waters, that could scarce stand,
being very wet and weak, with their wings
hanging on the ground; and that he hath
observed the swallows to be often weak for
some days after their appearance." The Swedish
naturalist, Alexander Berger, in the Calendar of
Flora, kept at Upsal, speaks of the swallow
retiring under water as a matter of course, and to
be expected at the proper season like any other
every-day event. September 17th, he enters,
"Hirundo submergitur." The swallow goes
under water. It has been suggested, indeed,
that the Upsal naturalist meant to write the
leech (Hirudo) and not the swallow (Hirundo),
in the entry in question, but we fear that
this is the suggestion of some wag, for the
evidence is too strong to be got over by
a mere printer's error. That wise and good
old naturalist, Gilbert White, half inclined to
the same opinion, and when he was residing at
Sunbury, on the banks of the Thames, he tells
us that in autumn he could not help being much
amused with the myriads of the swallow tribe
which assemble in those parts. "But what
struck me most," he adds, "was the fact that
from the time they began to congregate,
forsaking the chimneys and houses, they roosted
every night in the osier-beds of the aits of the
river. Now this resorting towards that element,
at that season of the year, seems to give
some countenance to the northern opinion
(strange as it is) of their retiring under water."
Even the illustrious Cuvier appears to have
added the weight of his authority to the notion
of submergence, for, speaking of the martin, he
says: "That it becomes torpid during the winter,
and even passes that season under water at the
bottom of marshes, appears to be certain."
It is scarcely necessary to use many
arguments to convince unbiased persons of the
untenability of this fancy. It is true that certain
animals hibernate that is, remain in a state of
torpidity during the cold weather. But they do
so under peculiar circumstances, having first
secured a warm and sheltered retreat in which
their animal heat is economised, and which is
within full reach of the effects of the returning
sun of spring. If such an animal be disturbed
during the cold weather, it may be prematurely
revived by the approach of warmth, or if left
exposed to the cold, it would infallibly die,
without recovering from its torpid condition.
The torpidity of hibernation, therefore, is a
natural physiological condition dependent upon
the diminution of temperature up to a certain
point, beyond which it is fatal. Nor could such
an animal revive in spring if its retreat were in
such a situation that the gradually increasing
heat of the sun in spring could not be felt.
Now, it is an established fact, that all places
situated at eighty feet below the surface of the
earth are constantly of the same temperature.
In these situations, therefore, the sun can have
no influence, and nothing else could call forth
dormant organs into action. The same cold
which benumbed them would evidently
perpetuate their slumbers.
But perhaps the best way to show the
fallacy of such a fancy is to examine the
statements of those who honestly believe that
they have been eye-witnesses of the supposed
fact; and such there are even now. It was
only five or six years ago that a lady of respectable
social position, living at Stockton-on-Tees,
wrote to the Darlington and Stockton Times,
asserting, that without any preconceived
opinions concerning the submergence theory,
she was herself a witness of the fact, and goes
on to relate that she, and a person with her,
saw a number of swallows dip under the water
at Middleton, a village on the banks of the
Tees, never rising from under it again. She
watched them most closely for a great length of
time, and was certain, of the fact. Now, here
we have a positive observation, made by an
educated lady, who, however, confesses that
"she is no adept in natural history," and
nothing can convince her that she was in any way
deceived, inasmuch as she not unnaturally
prefers the testimony of her own senses to the
dictum of closet naturalists.
Now, in examining into this statement, the
first thing which strikes us is the positiveness
of the observation. It is not easy to prove a
negative. We may say that the thing is
impossible. We may declare that no air-breathing
animal could exist beneath an element so
unfitted for its respiration as water. We may
strengthen our argument by calling to mind the
very active respiration of the class of birds, and
their very exalted animal heat. We may dwell
upon the necessary suddenness of the change
from air to water. We may argue that no
animals known to hibernate are believed to
submerge themselves; and we may clench the
matter by appealing to John Hunter's assertion,
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