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of oil, which it presses out with its beak, and occasionally anoints its feathers. In water fowl, this oil is so plentiful that it even imparts a degree of rancidity to the flesh, and we see that their coat of feathers is rendered by it completely water proof. The wings of birds are remarkably strong. The flap of a swan's wing would break a man's leg; and a similar blow from an eagle has been known to lay a man dead in an instant. The sense of seeing in birds is remarkably acute, and though they have no external ear, but only two small orifices or ear-holes, yet they do not seem to be deficient in hearing. The scent of some species is exquisitely delicate. In decoys, where ducks are caught, the men who attend them generally keep a piece of turf lighted, on which they breathe, lest the fowl should smell them and fly away. The voice of birds is much louder in proportion to their size, than that of other animals. The legs, the wings, the bones, and every part of the body are much lighter, firmer, and more compact in birds, than in other creatures. Their lungs are extended all over the cavity of their bodies. Carnivorous birds, like carnivorous quadrupeds, have but one stomach, and that well calculated for digestion. Those that feed on grain have, in addition to the crop or stomach where their food is moistened or swelled, a gizzard, which is a very hard muscle, almost cartilaginous or gristly, and which they commonly fill with small stones, where the food is afterwards ground in order to complete its digestion. Birds are subject to few diseases. Birds of the same species do not always make their nests of the same materials, though in general, there is a uniformity; the redbreast, in some parts of England, makes his nest of oak leaves, where those leaves are plentiful; in other parts, it makes it with moss and hair. Where the eggs are numerous, it is necessary to make the nest warm ; thus the wren, which is a small animal, and able to cover but a small compass, and yet lays many eggs, makes her nest remarkably warm; on the contrary, the plover, the eagle, the crow, &c. which lay but two or three, are not equally solicitous in this respect. There are some birds which are called birds of passage, and which by migrating, make a habitation in all parts of the earth; but in general, every climate has birds peculiar to itself. In all countries, birds are much longer lived than quadrupeds. They are, however, greatly inferior to quadrupeds in sense and docility. The rapidity with which birds move from place to place is one remarkable circumstance attending them. The hawk and many other birds, occasionally fly at the rate of not less than a hundred and fifty miles in an hour. Even the common crow moves twentyfive miles within that space of time; the swallow ninety two miles, and the eider duck ninety miles. This being the case, and it being known also that many birds can subsist for a considerable time without food, there can be no reason to wonder at birds being able to accomplish their periodical migrations to and from distant climes. The number of species in this class of animals is very numerous, amounting to above eight hundred.
FIS H E S . The number of fish to which a name is given, is, according to Linnaeus, above four hundred. The majority of these are confined to the sea, and would expire in the fresh water, though there are a few which annually swim up the rivers to deposit their spawn.
Wonderful as it may seem, to see creatures existing in a medium so dense, that men, beasts and birds must inevitably perish in it, yet experience proves that beside those species which we are in the daily habit of seeing, the very depths of the immense ocean contain myriads of animated beings, to whose very form we are almost strangers, and of whose dispositions and manners, we are still more ignorant.
The structure of fish, and their adaptation to the element in which they live, are eminent proofs of divine wisdom. Most of them have the same external form, sharp at each end and swelling in the middle, by which configuration they are enabled to traverse their native element, with greater ease and swiftness. From their shape, men originally took the idea of those vessels, which are intended to sail with the greatest speed.
But the progress of the swiftest sailing ship, with the advantage of a favorable wind, is far inferior to that of a fish. Ten or twelve miles an hour, is no small degree of rapidity in the sailing of a ship; yet any of the larger species of fish would play round her, as if she did not move, and even advance considerably before her.
The fins of fishes are denominated from their situations. The pectoral fins are placed at a little distance behind the opening of the gills, and are large and strong; they serve as well to balance the body, as to assist the motion of the fish. The ventral fins are placed towards the lower parts of the body under the belly, and serve chiefly to raise or lower the fish in the water. The dorsal fins are situated on the ridge of the back, and are very large in flat fish : their use, like the pectoral fins, is to keep the body well balanced, as well as to contribute to its forward motion. The anal fins are placed under the tail, enabling the fish to keep an upright position.
The chief instruments of a fish's motion are the fins, which in some fish are more numerous than in others. The fish in a state of repose, spreads all his fins, and seems to rest upon its pectoral and ventral fins near the bottom. If the fish folds up either of its pectoral fins, it inclines to the same side. When it desires to have a backward motion, striking with the pectoral fins in a contrary direction effectually produces it. If the fish desires to turn, a blow from the tail sends it about, but if the tail strikes both ways the motion is forward. In pursuance of these observations, if the dorsal and ventral fins be cut off, the fish reels to the right and left, and endeavors to supply its loss by keeping the rest of its fins in constant employment. If the right pectoral fin be cut off, the fish leans to that side ; if the ventral fin, on the same side, be cut away, then it loses its equilibrium entirely. When the tail is cut off, the fish loses all motion, and gives itself up to where the water impels it. The senses of fishes are remarkably imperfect, and indeed, that of sight is the only one which, in general, they may be truly said to possess. But this is, in some degree, compensated by their extraordinary longevity, several species being known to live more than a hundred years. Such is the general picture of these heedless and hungry creatures; but there are some of this class living in the waters, that are possessed of finer organs and higher sensations; that have all the tenderness of birds or quadrupeds for their young; that nurse them with constant care, and protect them from every injury. Of this class are the cetaceous order, or fishes of the whale kind. But the fierce unmindful tribe, who leave their spawn without any protection, are called the spinous, or bony kinds, from their bones resembling the sharpness of thorns.
If we emerge from the deep, the first, and most obvious class of amphibious animals that occur upon land, are frogs and toads. Then we find lizards of different kinds, as the crocodile, salamander, &c.
Frogs and toads, wherever they reside, seem equally adapted for living upon land, and in the water. The frog moves by leaping; the toad almost crawls upon the ground. The frog is light and active; the toad, slow and swollen, and incapable of much exertion. The frog is the best swimmer of all four-footed animals; the toad only creeps about in the mud.