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sophers have denied instinct to be that secret influence by which every species is impelled naturally to pursue, at all times, the same way or track, without any teaching or example; whereas reason, without instruction, would often vary and do that by many methods which instinct effects by one alone. Now this maxim must be taken in a qualified sense; for there are instances in which instinct does vary and conform to the circumstances of place and convenience.
It has been remarked that every species of bird has a mode of nidification peculiar to itself, so that a school-boy would at once pronounce on the sort of nest before him. This is the case among fields and woods and wilds; but, in the villages round London, where mosses and gossamer, and cotton from vegetables, are hardly to be found, the nest of the chaffinch has not that elegant finished appearance, nor is it so beautifully studded with lichens, as in a more rural district; and the wren is obliged to construct its house with straws and dry grasses, which do not give it that rotundity and compactness so remarkable in the edifices of that little architect. Again, the regular nest of the house-martin is hemispheric; but where a rafter, or a joist, or a cornice, may happen to stand in the way, the nest is so contrived as to conform to the obstruction, and becomes flat, or compressed.
In the following instances instinct is perfectly uniform and consistent. There are three creatures, the squirrel, the field-mouse, and the bird called the nut-hatch (sitta Europaea), which live much on hazel-nuts; and yet they open them each in a different way. The first, after rasping off the small end, splits the shell in two with his long fore-teeth, as a man does with his knife; the second nibbles a hole with his teeth, so regular as if drilled with a wimble, and yet so small that one would wonder how the kernel can
be extracted through it; while the last picks an irregular ragged hole with its bill: but as this artist has no paws to hold the nut firm while he pierces it, like an adroit workman, he fixes it, as it were, in a vice, in some cleft of a tree, or in some crevice; when, standing over it, he perforates the stubborn shell. We have often placed nuts in the chink of a gate-post where nut-hatches have been known to haunt, and have always found that those birds have readily penetrated them. While at work they make a rapping noise that may be heard at a considerable distance.-Natural History of Selborne.
6. The Motions of Birds.
A GOOD ornithologist should be able to distinguish birds by their air as well as by their colours and shape; on the ground as well as on the wing; and in the bush as well as in the hand. For, though it must not be said that every species of birds has a manner peculiar to itself, yet there is somewhat in most genera at least, that at first sight discriminates them, and enables a judicious observer to pronounce upon them with some certainty. Put a bird
Et verâ incessu patuit
Thus kites and buzzards sail round in circles with wings expanded and motionless; and it is from their gliding manner that the former are still called in the north of England gleads, from the Saxon verb glidan, to glide. The kestrel, or windhover, has a peculiar mode of hanging in the air in one place, his wings all the while being briskly agitated. Hen-harriers fly low over the heaths or fields of corn, and beat the ground regularly like a pointer or setting-dog. Owls move in a buoyant manner, as if lighter than the air;
they seem to want ballast. There is a peculiarity belonging to ravens that must draw the attention even of the most incurious-they spend all their leisure time in striking and cuffing each other on the wing in a kind of playful skirmish; and, when they move from one place to another, frequently turn on their backs with a loud croak, and seem to be falling to the ground. When this odd gesture betides them, they are scratching themselves with one foot, and thus lose the centre of gravity. Rooks sometimes dive and tumble in a frolicksome manner; crows and daws swagger in their walk; wood-peckers fly volatu undoso, opening and closing their wings at every stroke, and so are always rising or falling in curves. All of this genus use their tails, which incline downward, as a support while they run up trees. Parrots, like all other hooked-clawed birds, walk awkwardly, and make use of their bill as a third foot, climbing and descending with ridiculous caution. All the gallinae parade and walk gracefully, and run nimbly; but fly with difficulty, with an impetuous whirring, and in a straight line. Magpies and jays flutter with powerless wings, and make no dispatch; herons seem encumbered with too much sail for their light bodies, but these vast hollow wings are necessary, in carrying burdens, such as large fishes and the like; pigeons, and particularly the sort called smiters, have a way of clashing their wings the one against the other over their backs with a loud snap; another variety, called tumblers, turn themselves over in the air. Some birds have movements peculiar to the season of love: thus ringdoves, though strong and rapid at other times, yet in the spring hang about on the wing in a toying and playful manner; thus the cock-snipe, while breeding, forgetting his former flight, fans the air like the windhover; and the green-finch in particular, exhibits such languishing
and faultering gestures as to appear like a wounded and dying bird; the king-fisher darts along like an arrow; fern-owls, or goat-suckers, glance in the dusk over the tops of trees like a meteor; starlings, as it were, swim along, while missel-thrushes use a wild and desultory flight; swallows sweep over the surface of the ground and water, and distinguish themselves by rapid turns and quick evolutions; swifts dash round in circles; and the bank-martin moves with frequent vacillations like a butterfly. Most of the small birds fly by jerks, rising and falling as they advance. Most small birds hop; but wagtails and larks walk, moving their legs alternately. Skylarks rise and fall perpendicularly as they sing; woodlarks hang poised in the air; and titlarks rise and fall in large curves, singing in their descent. The white-throat uses odd jerks and gesticulations over the tops of hedges and bushes. All the duck kind waddle; divers and auks walk as if fettered, and stand erect on their tails: these are the compedes of Linnæus. Geese and cranes, and most wild fowls, move in figured flights, often changing their position. The secondary remiges of Tringe, wild-ducks, and some others, are very long, and give their wings, when in motion, an hooked appearance. Dabchicks, moor-hens, and coots, fly erect, with their legs hanging down, and hardly make any dispatch; the reason is plain, their wings are placed too forward out of the true centre of gravity; as the legs of auks and divers are situated too backward.-Natural History of Selborne.
ADAM SMITH was born at Kirkaldy in 1723, and received his early education in the grammar school of that place. In 1737 he was sent to the University of Glasgow, where he remained for three years, and then entered Balliol College, Oxford, as Exhibitioner on Snell's foundation. He appears to have resided at Oxford for about seven years, and is said to have there commenced the study of those moral and political sciences of which be became so great a master. He left Oxford in 1747, and resided at Kirkaldy and Edinburgh until, in 1751, he was elected Professor of Logic in the University of Glasgow. In 1752 he was further promoted to the chair of Moral Philosophy, which he filled for many years. It was during this time, in 1759, that he published his Theory of the Moral Sentiments.
In 1763 he resigned his professorship, and travelled for more than two years on the continent as tutor to the Duke of Buccleuch.
On his return in 1766, he again settled in Kirkaldy, and was for ten years occupied in the production of his great work, the Inquiry into the Nature and Causes of the Wealth of Nations, which appeared in 1776.
He survived its publication for fifteen years, and had the satisfaction of witnessing its effect in the commencement of that peaceful revolution of opinion, which, by reversing the policy of restriction and isolation, has been productive of such signal blessings to the nations of Europe. He died in Edinburgh in 1790.
Adam Smith is a great master of lucid and graceful exposition,