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American rivers swarm with these birds, and the traveller is often startled by the clouds which suddenly dart across the stream from their sandy hiding-places.
By what means does the sand-martin pierce through the solid materials of a bank? The slender beak" is the sole instrument, joined to perseverance; and this delicate agency accomplishes in time the object of the little feathered miner. The labour required in driving such a tunnel is of course great, but the work is finished in a few days, the roof with its arch-form constructed, and the chamber at the extremity formed, with that instinct-skill which so often appears in the works of the feathered engineers.
THE SWIFT (Hirundo apus).
This species might be called a large swallow by the general observer, as its habits do not much differ from those of the other Hirundines. It is not classed by all naturalists amongst the Hirundinidæ, receiving a distinct appellation (Cypselus apus), which is supposed to characterise the habits and appearance of the bird. This name signifies the footless hive-builder ; cypselus expressing its habit of building in holes of walls, and apus referring to the shortness of the feet. The former name has been given to this swallow since the days of Aristotle, but the Linnæan apus, seems not very unsuitable, as there can be little doubt respecting the claim of the swift to rank with the swallows. Linnæus classed it amongst the Hirundines, but he applied the term apus, or footless, to the bird, which is, of course, inaccurate, and so far objectionable. Cypselus murarius has been thought a fitter designation by Temminck, as mu ius denotes the swift's habit of frequenting ancient walls, and the hollows of grey ruins. But surely Hirundo murarius is sufficiently exact, avoiding the error implied by the word apus, and the fault of needlessly increasing the number of genera, to which objection the use of cypselus does certainly seem liable. The feet of the swift are so short as to unfit it for motion on the ground, on which it rarely alights. The toes are all in front of the foot, and so much curved, as to resemble the claws of the falcon. This structure enables the swift to cling firmly to the sides of perpendicular walls and rocks, which are its principal resting-places : and the feet are not designed for locomotion, but for a grasping apparatus. The long and powerful wings enable this bird of the airy realms to keep on the wing for sixteen hours through the long days of summer, when it may be seen disporting at immense heights, as if delighted to live beyond the many-voiced din of earth. Not till the last crimson rays have faded from the western clouds do the swifts descend from their high paths to roost in some ivy-clad tower or ruined castle-wall. Should sultry thunder-clouds gather along the horizon, the swifts are seen to dart to and fro, with exulting glee, as if eager to mingle in the strife of the tempest. Probably such weather brings within its
easy reach myriads of insects, and hence the bird's delight at such times can be explained on the most approved principles of utilitarianism.
The swift does not remain in England longer than three months, arriving about the middle of May, and leaving in August; it therefore has but one brood in the season, which being reared, the warm regions of the south are again sought. But, though the stay is short, the bird retains its summer home in memory, returning year after year to the same places. Dr. Jenner tested this habit of the swift, by taking from each of twelve birds two of their claws, by which mark he was able to recognise at the end of seven years one of the maimed birds in its former haunt.
The colour of the swift is a bright black, except the chin, which is white. Their hues become much dimmed by the nesting labours, and they consequently leave us in worn and soiled apparel.
This bird is not much of an architect, satisfying itself by a rude nest of dry vegetable matter and feathers.
THE JAVA SWALLOW (Hirundo esculenta).
Our limited space prevents more than a brief notice of this bird, which indeed offers little to attract attention, if its nests are excepted. Some birds gain ornithological distinction by their modes of life; this derives its importance from its house. The term esculenta (eatable) applies of course to the nest, not to the bird, and is therefore a clumsy epithet when connected with the word Hirundo. Asiatic, Indian, or Java swallow would be a more correct designation. The nests of this bird are formed from certain portions of its food, and are collected with the utmost care by the natives of the Chinese seas, who risk their lives to procure from precipitous rocks these prized specimens of bird-manufacture. The matter of which these nests are composed is sold in the Chinese markets, at a cost equal to thirty shillings of our money for a pound's weight, and is used for soup. The nests are reduced to a substance resembling isinglass, after twenty-four hours' boiling. More than 2500 Ìbs. weight of these nests are collected yearly in Java, and, as each nest weighs about half an ounce, the number taken must be immense. Men have thus laid a swallow under contribution to increase their luxuries, and from the substance of a bird's nest extracted piquancy for their dishes. Some
have imagined these singular nests to be formed from the scum floating on the sea, or from sea plants, but this supposition appears unfounded.
Goldsmith is a little irritated when writing of this eastern food, exclaiming sarcastically, “What a pity this luxury hath not been introduced among us, and then our great feasters might be enabled to eat a little more
Here must terminate this account of the swallows, which are often in tens of thousands rejoicing amongst us, and enlivening by their beautiful forms the banks of our gentle streams and broad rivers, whilst over tangled copses, and across flowery meads, these birds of brightness wheel in their fulness of delight.
The Caprimulgidae, or Goatsuckers. “ THE goatsucker!" exclaims the reader ; " where do such birds live? and what kind of goats allow themselves to be robbed of their milk by birds ?" These are questions to the point; but thou must know, O reader, that as names do not always answer to the real nature of human things, so neither do they at all times suit the properties of animals. An epithet once attached, whether to a man or an empire, clings for ages, and is applied long after the discovery of its inappropriateness; so it is in Natural History, and thus the name goatsucker has prevailed from the days of Aristotle to the present age.
Men deem old names consecrated things, and are jealous of interference with the venerable word which they have read in “ the ancient books” and heard from the lips of fathers and grandfathers. This reverence for olden things is right, for it is a just respect for the thinkers by whose thoughts we nourish our intellectual life; let it not, however, lead us to consecrate error. Antiquity has a venerable form, but truth is more holy than age, and brighter than the brightest lights in the hands of erring sages. Therefore we must pronounce the name of goatsucker, and its Latin equivalent, caprimulgus, a gross blunder. There are no known birds which suck the teats of goats, nor is it likely that
such will ever be discovered. But, it may be said, the term goatsucker has long been applied to a certain bird; here is an effect, surely there must have been a cause. Most certainly there was a cause, but of what nature ?
It was formerly supposed that goats, when left on lonely heaths in summer, were sucked by a certain migratory bird; the supposition grew, and such suppositions have a wondrous power of growth, into a fixed belief, and from this arose the bird's peculiar
But whence this notion itself? During the dry months of summer, it often happened that the goats yielded little milk; this result was natural enough; but a bird was then frequently seen, in the faint twilight, flitting with a singular motion over the Jonely moors, and even amongst the browsing goats themselves. What could' that bird want, thought the suspicious goatherd, in such a place? Ignorance and suspicion, two potent marvelworkers, soon found reply, and “ goatsucker” became for ages the name of a most harmless bird. Learning sanctioned the delusion, and wrote caprimulgus in her records. This ancient judgment has been reversed; the bird is no longer accused of milk-stealing ; but the old term still stands, and we find caprimulgus yet used in our scientific works. And why have we employed the title at the head of this chapter? With the same object for which the pillory was used of old: to expose, not to exalt, wrong; and it was also necessary to retain this name in a book intended for general use, that none might be puzzled by a new or unknown name. The bird of which we speak has a variety of appellations ; some call it the night-hawk, but this is incorrect, for the bird'has no hawklike propensities, and has never been known to kill another bird for prey. Some eminent naturalists apply the name fern-owl, which is a decided misnomer, the bird having no relation to the owl family. It certainly makes its home amongst patches of fern, and might therefore be called the fern-bird ; but why add the epithet owl? Is this because the bird flies abroad in the grey twilight? then, for the same reason, the bat might be called an owl.
Jenyns and the enthusiastic Gould' think night-jar a more appropriate designation for so singular a bird ; and they are right, as this name does really express the peculiar habits of the bird. It comes abroad after sunset, and utters a singular jarriny or buzzing sound, which may be said to jar or grate upon the ear in the evening stillness. Thus the name of night-jar" is not altogether inappropriate, though “jar” is not the word most expressive of the musical hum uttered by this bird.
Whilst flying, a sound resembling the hum of a spinning-wheel is given out, from which circumstance come the names, " nightjar," night-churn,” “churn-owl,” and “wheel-bird;" alì of
Those who are acquainted with this persevering ornithologist will understand the application of the term “ enthusiastic.