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sort to our shores, there are but few that breed here: the tame swan and goose, the sheldrake, the eider duck, the wild duck, the teal, and the shoveller duck, are all the species that usually breed with us. The rest contribute in forming that amazing multitude of water-fowl, which annually migrate from the southern parts of Europe to the woods and lakes of the dreary regions of Lapland. There they 'perform the duties of incubation and nutrition in perfect security; and from these vast and solitary retreats they issue in September, and disperse over the whole of Europe. There are few of this numerous genus, which, in obedience to the first great dictate of nature, may not be traced flying to the arctic regions, a country of lakes, rivers, swamps and mountains: there' the thick and gloomy forests not only afford them shelter and security, but also, by keeping the ground moist and penetrable, afford the snipe, woodcock, and other slender-billed birds, the means of collecting their food; while the web-footed birds find abundance in the larvæ of insects, which are there deposited in vast quantities on the waters
In these places the days are long; and the beautiful meteoric nights afford them every opportunity of collecting so minute a food, which is probably more grateful than any other, and which the all-bountiful CREATOR has spread for them so redundantly in the wilderness. It is therefore no longer a matter of astonishment, that such vast numbers of fowl should descend from these regions on the approach of winter, numbers which far exceed the army of Xerxes, and which Linnæus observed for eight whole days and nights to cover the surface of the river Calix, as he proceeded along its banks.
These migrations generally commence in the middle of September, when they quit their retreats to disperse over Europe. The order of their flight is pretty remarkable; they either follow each other in a long line, or march in an angular form, the two lines meeting each other at a sharp point. The bird which leads the van cleaves the air, and facilitates the passage of those that follow: when fatigued in this laborious station, he falls back into one of the side files, and is replaced by another, who leads on the whole body in his place. With us they make their appearance about the beginning of October; circulate first round our shores; and, when the frost compels them, betake themselves to our lakes and rivers. There are some of the web-footed fowl of hardier constitutions than others; these endure the ordinary winters of the northernmost climates, but, when the cold reigns over them with more than common rigour, they repair for shelter to these kingdoms. Hence the divers, the wild swan, the swallow-tailed sheldrake, are not constant visitors; their appearance is regulated by the severity of the winters in their native abodes.
That animals so dull and irrational should be able to accomplish such long journies, should know where to direct their course, or when to undertake it, has been a matter of just surprise. It is probable they are guided in this, as in every thing else, by the strong impulses of an instinct under which they seem wholly passive. Their accustomed food no sooner begins to fail, or the climate to be disagreeable, than they meditate a retreat to better accommodations. In migrating birds, the change of residence is a kind of natural waạt, which manifests itself strongly, even when in a state of captivity. At the two seasons of migration, the quail, although confined, discovers the utmost inquietude; leaves nothing unattempted to procure liberty; and the violence of its efforts to escape often occasions its death. Impelled, then, by so powerful an instinct, it is probable that birds obey its call without foreseeing the advantages to be gained by a removal, or anticipating the dangers of encountering the winter in the same country. They seem not to have any recollection of those places where they spent former seasons. They cannot possibly survey the countries where they are to take up their abode, from their immense distance, and the rotundity of the globe. They appear to be guided by the climate, rather than the country; and as soon as they find the former suited to their wants, they are determined in their choice of the latter.
The variety of opinions which naturalists have adopted concerning the departure and winter residence of our summer birds, fully evinces the obscurity of this portion of their history. It is universally agreed, that the swallows in every part of Europe regularly disappear before the commencement of winter; and the most general and probable opinion is, that they remove beyond the Mediterranean to the warmer climates of Africa, to spend the winter in a country where they find a continuance of their natural food, and a temperature of air suited to their. constitutions. In confirmation of this opinion, Mr. Adanson asserts, that, during his long residence at Senegal, he constantly observed swallows arriving there about the same time that they leave Europe. They have been frequently seen by sailors alighting on the rigging of ships, to rest themselves during their long passage from the one continent to the other. They are perceived too, like the quails and storks, to collect together in large flocks for some days before their departure; after which, they regulariy disappear.
While the annual migration of the house-swallow seems thus ascertained by facts, observations, and analogy, another opinion has been formed, and with some appearance of evidence, that they pass the winter in a dormant state, in rocks, banks, and even in lakes, at the bottom of the water. This notion has been supported by authors of credit and respectability. Some northern naturalists positively assert, from their own knowledge, that they have been dragged in nets, from the bottom of lakes, in a torpid state. Mr. Collinson has given the evidence of three gentlemen, eye-witnesses to numbers of sand-martins being drawn out of a cliff on the
Rhine; and the Hon. Daines Barrington, in his Trea- · tise on the Migration of Birds, asserts, that they do not fly over any large surface of water, but reside under it all the winter in a state of hybernation, or winter-sleep.
Where do the cranes, or winding swallows, go?
PRIOR. Several of our countrymen have given credit to the submersion of swallows. M. Klein patronises the doctrine strongly, and gives the following account of their retreat, which he received from his countrymen. They assert, that the swallows assemble in numbers, on a reed, till, broken by their weight, it sinks with them to the bottom; and as a prelude to their immersion, they sing a dirge of a quarter of an hour's length: that many unite in laying hold of a straw with their bills, and thus plunge down in social compact into their subaqueous retreat; that others again form a large mass by clinging together with their feet, and thus commit themselves to the deep. It is related by Olaus Magnus, archbishop of Upsal, that when the fishermen discover such masses, they bring them to life by thawing the birds at a fire; but owing to a premature and forced revival, they continue but a short time to enjoy it: and Mr. Heerkens, a celebrated Dutch naturalist, in a Latin poem on the birds of Friesland, speaks in positive terms of the torpid state, and submersion, of the swallows:
Ere winter his somnif'rous power exerts
In opposition to this view of the subject, it has been observed by M. Buffon, that the house swallow, at least, is incapable of subsisting in a be numbed or torpid state. Those which he placed in an ice-house uniformly perished, and gave no symph toms of revival on the application of heat. He supposes, however, that there may be other species of swallows capable of such a state of hýbernation. Mr. John Hunter asserts, that, in swallows, the organs of respiration are very differently formed from those of the animals that sleep during winter; and he justly condemns the opinion of any terrestrial animal being able to support life for any length of time under water.
Although there are abundance of lakes in Britain, yet there is no well attested instance of swallows having been found in a state of torpor and immersion: till such is found, we are surely excusable in suspending our belief. What may have given rise to the above opinions is, that there remain annually some birds of later flights, who, unable to bear the fatigues of so long a voyage, have not attempted it, and are found destroyed by the rigours of winter. If their nests have, by any accident, been demolished, they are known to lay a second and sometimes a third time: not being able to carry off, at the usual term, their tender offspring, rather than abandon them, they prefer suffering with them the inclemency of the season and certain death.
Besides those birds that remain stationary in the country during the whole year, and those that regularly migrate at particular seasons, there are some that may properly be styled passengers; by which title is understood, such as are found in a particular country only for a short time, as they pass from their summer to their winter residence. In North Britain the king-fisher and Bohemian chatterer come under this description; while a fourth class of birds have been denominated wanderers, from their pass