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and wheel, in their full felicity, for hours, floating without effort in that rare expanse which others of the feathered tribes use chiefly as a highway and not a home. No birds touch the earth so rarely as the swallows; and for this aërial life their structure is beautifully adapted. Look at one as it comes sweeping along the village road, within a few inches of the ground, which it touches not, and passes close by your person, as if conscious of your inability to harm or seize it during that arrowy flight. Watch the bird with a keen eye, for there is little time for observation with such a winged machine. Did you mark the shape of its body? What work of human science does it most resemble? See how full the fore part of the animal is ; mark how it tapers gradually towards the tail; and then remember that such is the principle upon which the fastest sailing ships are constructed. Thus the highest skill of the ship-builder only aims to develope the mechanical principle upon which every swallow is organised. The plumage is also peculiarly fitted to promote Alight, being firmly compacted, and so not liable to be ruffled by the breezes encountered in these rapid and long voyages, which excite our wonder and admiration. The wings resemble oars of great power, and are moved by muscles of singular force; whilst the long forked tail supplies a never-failing rudder to guide this bird through those numerous windings in which it delights. The food is seized during flying, and this requires a peculiar construction of the mouth, and also the keenest powers of sight. We accordingly find that the swallow's mandibles open as far back as the eyes, thus producing a large gape, in which insects are caught as by a net.

There are five or six varieties of the swallow family; the most known in England being the chimney-swallow, house-martin, sand-martin, and swift, all of which are familiar to us.

THE CHIMNEY-SWALLOW (Hirundo rustica, or

Hirundo domestica). This species arrives here in April, often during the early part of the month, and forms the van of the great swallow army, reaching England about twenty days before the martins. The English name arose from its selection of chimneys for resting localities. These places are generally chosen by the bird, though it sometimes builds in the shafts of old coal-mines, which the swallow may deem good substitutes for chimneys.

The Latin designation, Hirundo rustica (rural swallow), given by Linnæus, is not well applied, as it will suit the rest of the swallows quite as well. Hirundo domestica (house, or tame swallow), given by Ray, would be more appropriate ; but this would apply with a stricter truth to the martin. We must not, however, quarrel with these long-appropriated names, especially as no inconvenience can now attend their use. Whence come these swallows ? From the sunny land of Africa: thither they have been traced, and thence their track has been observed, when spring calls them to the bright lanes and meads of England.

« The swallow knows her time,
And on the vernal breezes wings her way
O'er mountain, plain, and far extending seas,

From Afric's torrid sands to Britain's shores." It is probable that chimney and other swallows do not travel direct from England to Africa, but proceed through Spain, Italy, and Greece to that continent. It is supposed that they penetrate far into Africa, as Bruce saw them in Abyssinia during winter. What a range for these beautiful birds! In winter sporting round the fountains of the Nile, sweeping over the pyramids, and uttering their happy twitter amid the ruins of Thebes ; in summer, skimming the waters of the Thames, and nestling in “ Windsor's proud keep;” whilst autumn brings them to the walls of the Alhambra and the arches of the Colosseum. The chimney-swallows do not arrive in a compact body; certain small bands precede, and scatter themselves thinly over the country, appearing during the short intervals of calm and sunshine. From these scanty arrivals arose the proverb, one swallow does not make summer ;” which is found in most of the European languages. As swallows moult in their torrid homes, before undertaking their great spring journey, they come to us clothed in the first brightness of their plumage, which is not tarnished by their rapid flight over sea and land. We can, therefore, easily distinguish the different varieties, by attending to certain diversities of colour before the brilliancy becomes dimmed by their nestling labours. The chimney-swallow may be distinguished by three particulars — by the reddish mark on the throat, whereas the martin is snow-white in that part; the tail is also more forked than the house swallon, which is caused by the great length of the outside tail-feathers; and by the colour of its belly, which is a reddish white. This last circumstance, with the throat-spot, will enable us to tell whether one of these birds on the wing is the chimney-swallow or martin, as such peculiarities are more easily noticed during the numerous windings of the bird, than the comparative length of the tail.

The plumage of this swallow is somewhat dimmed by descending into sooty chimneys, which, with its naturally dusky colours, renders the Hirundo domestica less beautiful than the martin. It exhibits, nevertheless, the most brilliant steel-blue tints on the back and wings, which are best observed when the bird is sweeping along the surface of a road or meadow, close to the ground; then we can easily discern the radiancy of each tint, as the little insect-hunter passes rapidly to and fro. The localities most prized by this swallow are buildings near water, over which they hunt for food,

“I delight to see
How suddenly he skims the glassy pool;
How quaintly dips; and with an arrow's speed

Whisks by.In such places every chimney has a fair chance of being occupied by these busy tenants, to the no small discomfort of thrifty housewives on the approach of winter, when the accumulated mass of nests either prevents the kindling of a fire, or causes the destruction of the chimney by its combustion. It might be imagined the unpleasant circumstances of soot and smoke would deter so elegant a bird from building in such places; but warmth and security repay the swallow for those nuisances. This propensity to build in chimneys cannot be gratified by the bird in those districts uninhabited by Europeans, or where chimneys are unknown. In such countries this swallow recurs to its natural nesting-places, the hollow trunks of old trees, in which thousands are often found roosting. This is the case in the unpeopled wastes of America, where certain time-worn trees have been for many generations named “swallow-trees,” being, in fact, the homes of countless hosts of these birds. In some parts this swallow is said to prefer barns and out-houses to chimneys, which is the case in Sweden and Scotland. Does this arise from the fuel used in such places producing a soot of an unpleasant and irritating nature? There is, doubtless, a law regulating the choice of the nest by a bird, which is not less founded on nature than the principles which originate the bird's existence. Hence the selection of chimneys and hollow trees in some countries, and the avoidance of them in others, is not a result independent of ornithological laws. The nests of the chimney-swallow differ from the martin's house in one particular; it is open at the top, whereas the martin has a roof to its abode, and the entrance is in the side-a diversity of architecture required by the distinct habits of the two birds.

The chimney-swallow, in leaving its nest, must dart upwards to reach the top of the shaft; in descending, the bird's object is to alight directly on the nest entrance. Both operations require the nest to be open at top. The martin launches horizontally from its nest, and, sweeping back to the entrance, finds its door exactly before it—a circumstance required by the frequent journeyings of the bird to and fro. The chimney-swallow does not often use again the nest of the previous year, preferring to construct a new residence, which it frequently raises on the old nest, thus piling tier upon tier, and, in some chimneys, forming a complete lining of its mud and straw work. The eggs are white, with brown or reddish spots, representing, by their diversified surfaces, the varied plumage of the blithe creature which in due time emerges from those little inclosures of bird-life.

The food of the swallows consists wholly of insects, which they catch whilst flying. The velocity of their movements prevents the observer from seeing the capture of the prey, but the event is notified by a peculiar sharp snap, which is easily heard, and arises from the rapid closing of the mandibles upon the insect.

Most persons accustomed to walk in the country have experienced the torment produced by insects flying into the eye, and the difficulty of extracting these little persecutors. Such insects are principally of one kind, and so small that we are unable to avoid their sudden darts, whilst their sharp spiky members lacerate the tender eyes. But these are just the insects most sought by the chimney-swallow, and by all this fainily of birds. Frequently this member of the Hirundinidæ may be seen high in the air pursuing a species of spider, which rises in fine weather to immense elevations.

When we look up into the clear blue sky, we may suppose that all is mere aërial space, that life moves not in these cloudless deeps. In this we are wrong, as great numbers of insects are as well fitted to live in these altitudes as fish to exist in the rivers beneath. In the pursuit of such high-soaring insects the swallow rises, until our eyes are unable to detect its form. But when the storm is gathering, and murky clouds conceal the sun's brightness, the insect swarms descend, and the swallow likewise follows their descent. Hence, the low flight of these birds is supposed to indicate the approach of wet weather or storms, and their higher ranges the continuance of fine weather. This opinion is often true;

but the swallow's low flight does not always precede lowering weather, being often caused by the little elevation at which some insects float. As the swallow is entirely insectivorous, it renders important services by destroying vast quantities of insects, which, if allowed to increase without check, would prove a source of most grievous annoyance to man. Thus, when swallows bave been destroyed in the neighbourhod of hop-grounds and orchards, great injury has resulted to the crops from insect blights. There are myriads of small and active insects, which few birds can destroy except the swallow; it alone is able to continue the pursuit, through the most rapid and serpentine windings. Some hundreds of insects are probably destroyed every day by a pair of these birds; the annual number consumed by all the swallows must therefore be incalculable. A year without swallows would bring upon our fields and gardens a plague like that of Egypt. Let us, therefore, rejoice in the appearance of these beautiful birds, the habits of which are so interesting and full of advantage to mankind.

The many hours which these birds continue on the wing, and the rapidity of their flight, cause them to pass over immense

spaces during their lives. Wilson makes a calculation, which gives eighty-nine times the circumference of the globe as the space passed over by a swallow in ten years, to which period most of the birds live. He supposes the Hight to equal one mile a minute, and that the swallow is on the wing for ten hours out of every twenty-four. This, in ten years, gives 2,190,000 miles, about eighty-nine times the circumference of the earth : a distance which, perhaps, no creature except a swallow ever passes over. Motion is a law of life in most of its forms, but such motion is peculiar to these bright and happy living things.

It is often remarked that nothing in the universe of life presents us with unalloyed ease; the swallow is no exception to this wide law. It might be imagined that those purplish-coloured, merry, and

twittering creatures must be without the least degree of pain. We naturally connect such elasticity with joyousness of life. That such is the main character of the swallow's existence, cannot be denied. Where, then, is the pain ? It is found in the multitude of insects which cling to the close plumage of the swallow, and which its rapid and almost incessant flying cannot shake off. Beneath those beautifully-tinted feathers, glowing like rainbow hues in the sunlight, lurk the plagues of the swallow's life. Such insects are not found in the bird when it first reaches our island; but the warmth of the nest, and the close places in which the swallow often builds, soon develope the annoyance; and the chimney-swallow appears to suffer most. So grievous is the infliction, that the bird is reduced to an almost helpless state, and has then been caught by persons who have found the feathers laden with a large insect, called by some Ceuterina hirundinis, or by others the Hippobosca hirundinis. The long period during which the young continue in the nest before flight may cause this evil, by rendering the nests foul, and so favouring the development of these troublesome insects.

After the nesting season is over, the birds live more in the coolness of the open air, when the pest diminishes ; and their long autumnal journey over the seas probably frees the poor birds from the annoyance altogether.

At the end of September the swallows prepare to seek more sunny homes than we can give them. They cling as long as possible to the loved localities where their young have been reared as if willing to stay; but the low sighing of the equinoctial gales, and the diminishing brightness of the days, force these birds of summer to seek their loved sunny rays in southern lands. Sometimes the rustic sees their assembled thousands congregating on the village roofs, like some colony of old preparing to leave its ungenial home in the northern forests, for the attractive plains of the south.

But as such human migrations were met by enemies, and for a time repelled, so the swallows are often driven back by the

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