[28] These three points are common to most insects, and ought therefore not to be made characteristics of any particular species. They are called Stemmata, and are a kind of eyes which serve the insects for looking at distant objects, as the compound eyes do for objects near at hand. F. [↑]
[29] It has been a subject of contest among naturalists, to determine the winter-retreat of Swallows. Some think, [[141]]they go to warmer climates when they disappear in the Northern countries: others say, they creep into hollow trees, and holes in clefts of rocks, and ly there all the winter in a torpid state: and others affirm, that they take their retreat into water, and revive again in spring. The two first opinions have been proved, and it seems have found credit; the last has been treated as ridiculous, and almost as an old woman’s tale. Natural history, as all the other histories, depends not always upon the intrinsic degree of probability, but upon facts founded on the testimony of people of noted veracity.—Swallows are seldom seen sinking down into the water, Swallows have not such organs as frogs or lizards, which are torpid during winter, ergo, Swallows live not, and cannot live, under water.—This way of arguing, I believe, would carry us, in a great many cases, too far; for tho’ it is not clear to every one, it may however be true: and lizards and frogs are animals of a class widely different from that of birds, and must therefore of course have a different structure; hence it is they are classed separately. The bear and the marmot are in winter in a torpid state, and have however not such organs as lizards and frogs; and no body doubts of their being, during some time, in the most rigid climates in a torpid state: for the Alpine Nations hunt the marmots frequently, by digging their holes up, and find them so torpid, that they cut their throats, without their reviving or giving the least sign of life during the operation; but when the torpid marmot is brought into a warm room and placed before the fire, it revives from its lethargy. The question must therefore be decided by fact; nor are they wanting here: Dr. Wallerius, the celebrated Swedish Chemist, wrote in 1748, September the 6th O. S. to the late Mr. Klein, Secretary of the City of Dantzick: “That he has seen more than once Swallows assembling on a reed, till they were all immersed and went to the bottom; this being preceded by a dirge of a quarter of an hour’s length. He attests likewise, that he had seen a Swallow caught during winter out of a lake with a net, [[142]]drawn, as is common in Northern countries, under the ice: this bird was brought into a warm room, revived, fluttered about, and soon after died.”
Mr. Klein applied to many Fermiers generaux of the King of Prussia’s domains, who had great lakes in their districts, the fishery in them being a part of the revenue; in winter the fishery thereon is the most considerable under the ice, with nets spreading more than 200 or 300 fathoms, and they are often wound by screws and engines, on account of their weight. All the people questioned made affidavits upon oath before the magistrates. First, The mother of the Countess Lehndorf said, that she had seen a bundle of Swallows brought from the Frish Haff (a lake communicating with the Baltic at Pillau) which when brought into a moderately warm room, revived and fluttered about. Secondly, Count Schlieben gave an instrument on stamped paper, importing, that by fishing on the lake belonging to his estate of Gerdauen in winter, he saw several Swallows caught in the net, one of which he took up with his hand, brought it into a warm room, where it lay about an hour, when it began to stir, and half an hour after it flew about in the room. Thirdly, Fermier general (Amtman) Witkowski made affidavit, that in the year 1740, three Swallows were brought up with the net in the great pond at Didlacken; in the year 1741, he got two Swallows from another part of the pond, and took them home, (they all being caught in his presence); after an hour’s space they revived all in a warm room, fluttered about, and died three hours after. 4thly, Amtman Bönke says, that having had the estate Kleskow in farm, he had seen nine Swallows brought up in the net from under the ice, all which he took into a warm room, where he distinctly observed how they gradually revived; but a few hours after they all died. Another time his people got likewise some Swallows in a net, but he ordered them again to be thrown into the water, 5thly, Andrew Rutta, a master fisherman, at Oletsko, made affidavit, 1747, that 22 years ago, two Swallows [[143]]were taken up, by him, in a net, under the ice, and being brought into a warm room, they flew about. 6thly, Jacob Kosiulo, a master fisherman, at Stradauen, made affidavit, that in 1736, he brought up in winter, in a net, from under the ice of the lake at Raski, a seemingly dead Swallow, which revived in half an hour’s time, in a warm room, and he saw, a quarter of an hour after, the bird grow weaker, and soon after dying. 7thly, I can reckon myself among the eye-witnesses of this paradoxon of natural history. In the year 1735, being a little boy, I saw several Swallows brought in winter by fishermen, from the river Vistula, to my father’s house, where two of them were brought into a warm room, revived, and flew about. I saw them several times settling on the warm stove, (which the Northern nations have in their rooms) and I recollect well that the same forenoon they died, and I had them, when dead, in my hand.
In the year 1754, after the death of my uncle Godefroy Wolf, captain in the Polish regiment of foot guards; being myself one of his heirs, I administered for my co-heirs, several estates called the Starosty, of Dirschau, in Polish Prussia, which my late uncle farmed under the king. In January the lake of Lybshau, belonging to these estates, being covered with ice, I ordered the fishermen to fish therein, and in my presence several Swallows were taken; which the fishermen threw in again; but one I took up myself, brought it home, which was five miles from thence, and it revived, but died about an hour after its reviving. These are facts, attested by people of the highest quality, by some in public offices, and by others, who, tho’ of a low rank, however made these affidavits upon oath. It is impossible to suppose indiscriminately that they were prompted by views of interest, to assert as a fact, a thing which had no truth in it. It is therefore highly probable, or rather incontestably true, that Swallows retire in the Northern countries during winter, into the water, and stay there in a torpid state, till the return of warmth revives [[144]]them again in spring. The question therefore I believe ought for the future to be thus stated: The swallows in Spain, Italy, France, and perhaps some from England, remove to warmer climates; some English ones, and some in Germany and other mild countries, retire into clefts and holes in rocks, and remain there in a torpid state. In the colder northern countries the Swallows immerse in the sea, in lakes, and rivers, and remain in a torpid state, under ice, during winter. There are still some objections to this latter assertion, which we must remove. It is said, Why do not rapacious fish, and aquatic quadrupeds and birds, devour these Swallows? The answer is obvious. Swallows chuse only such places in the water for their winter retreat, as are near reeds and rushes; so that sinking down there between them and their roots, they are by them secured against the rapaciousness of their enemies. But others object, Why are not these birds caught in such waters as are continually harrassed by nets? I believe the same answer which has been made to the first objection, will serve for this likewise. Fishermen take care to keep off with their nets from places filled with reeds and rushes, for fear of entangling and tearing their nets; and thus the situation of Swallows under water, is the reason that they are seldom disturbed in their silent winter-retreats. What confirms this opinion still more is, that Swallows were never caught in Prussia, according to the above-mentioned affidavits, [[145]]but with those parts of the net which passed near to the reeds and rushes; and sometimes the Swallows were yet fastened with their feet to a reed, when they were drawn up by the net. As to the argument taken from their being so long under water without corruption, I believe, there is a real difference between animals suffocated in water, and animals being torpid therein. We have examples of things being a long time under water; to which we may add the intense cold of these northern regions, which preserves them. Who would have thought it, that snails and polypes may be dissected, and could reproduce the parts severed from their body; if it was not a fact? Natural history ought to be studied as a collection of facts; not as the history of our guesses or opinions. Nature varies in an infinite manner; and Providence has diversified the instinct of animals, and their œconomy, and adapted it to the various seasons and climates. This long digression I thought necessary and excusable; and the more so, as the ingenious great friends to the cause of Natural History, the late Mr. Collinson, and Mr. Pennant, have both asserted the impossibility and improbability of this immersion. I revere the memory and the ashes of the one, and think the friendship of the other an honour to me: but am assured, that both prefer truth to their private opinion; and can bear a modest opposition, when it is proposed with candour, with a view to promote truth, and with sentiments of respect and gratitude, as it is done by me, in the present case. F. [↑]
[30] Hirundo, caudâ aculeatâ, Americana. Catesb. Carol. vol. iii. t. 8. [↑]
[31] Hirundo purpurea. Nat. Hist. of Carol. vol. i. t. 51. [↑]
[32] It must be carefully distinguished from what is called Currants, in England, which is the Ribes rubrum. F. [↑]
[33] Cratægus tomentosa, Linn. Spec. Pl. p. 682. [↑]
[34] Mespilus inermis, foliis ovato-oblongis, serratis, subtus tomentosis. Gronov. Fl. Virgin. 55. [↑]
[35] Caprimulgus minor Americanus. Catesb. Nat. Hist. of Carolina, Vol. iii. t. 16. Edwards’s Nat. Hist. of Birds, t. 63. [↑]