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from intimate society with other fowls, not joining the Geese in their gregarious disposition to form one common flock, nor yet, like the Muscovy Duck, attaching itself to the Hens and Turkeys, but maintaining a very independent, fearless, and somewhat haughty exclusiveness.

THE MUSK (COMMONLY MUSCOVY) DUCK.

"At Makaaka, we saw some Muscovy ducks feeding in the garden, and offered to purchase one; but they said they were rearing them for their landlord, and could not part with any; they furnished us, however, with a fowl, with which, and some biscuit we had with us, we made a tolerable meal."-ELLIS's Missionary Tour through Hawaii, p. 187.

"CAN a Duck swim?" is a pert question sometimes asked with little expectation of an answer in the negative. Here, however, is a Duck, which if it can swim, performs that action in such a clumsy way as hardly to deserve the name of swimming. Those who expect that its singular appearance "would render it a curious, if not an elegant companion, among the more attractive Ducks of our aquatic preserves," will be disappointed; for it will never go near the water, if it can help it, but will prefer the farm-yard, the precincts of the kitchen, or even the piggery itself, to the clearest stream that ever flowed. In fact, it hates water, except some dirty puddle to drink and drabble in. When thrown into a pond, it gets out again as fast as it can. It does, indeed, sometimes seem to enjoy an occasional bath, but so does a sparrow or a canary bird. Its very short leg does not appear to be mechanically adapted for the purpose of swimming. It waddles on the surface of a pond as much as it does on dry land; it is evidently out of its place in either situation. Its proper mode of locomotion is through the air; its congenial haunts are among the branches of

trees.

The early Voyagers and the old Ornithologists are constantly referring to these habits. Observe, for instance, the description of "A wild Brazilian Duck of the bigness of a Goose.-Marggrave. It hath a black Bill, dusky Legs and Feet. It is all over black except the beginnings

(setting on) of the Wings, which are white; but that black hath a gloss of shining green. It hath a crest or tuft on its head consisting of black feathers, and a corrugated red mass or bunch of flesh above the rise of the upper Mandible of the Bill. It hath also a red skin about the Eyes. It is very fleshy, and good meat. They are commonly shot sitting on high trees: For after they have washt themselves in cold water, they fly up high trees, for the benefit of fresh air and Sun."- Willughby.

A pair that were given to me by a friend came home very dirty, and, as at the end of three or four days they still had not washed themselves from their coating of filth, they were driven towards the water to bathe and be clean. In vain-they flew back over our heads to the poultry-yard; and we were obliged to catch them, put them into the pond with our hands, and give them a ducking whether they would or not.

Another curious fact is, that great part of the feathers of the Musk Duck do not resist the wet so well as those of other water-birds; but the quill feathers particularly, and those of the tail, become soaked and matted in a very few minutes, like those of a Hen or Turkey; so that if compelled to make any long voyage, at a certain distance, they would sink and be suffocated. It would not be a humane experiment to try to make a Duck drown itself; but such would probably be the result. We have here, then, the strange anomaly of a web-footed bird, whose feathers do not repel water; which may be matched by another case, the Water-Hen, a bird whose feet have no web whatever, which yet swims safely though not quickly, and whose feathers are waterproof. Woodcocks, also,

have been said to rest on the surface of the sea during their migrations: the common Heron has been stated by Mr. Yarrell, on good authority, to swim occasionally; and Audubon positively affirms that he has known a flock of wild Turkeys cross an American river by swimming. The correctness, however, of this last account has been called in question, but, as it is impossible to prove a

negative, not disproved. Mr. Darwin also, whose name is a sufficient guarantee for the accuracy of the fact, states, I think, the same thing of the American Ostrich.

The cause of this difference in the wet-repelling power of the feathers of different birds remains yet to be discovered. The old idea of the function of the oil-gland on the rump needs no further refutation. The quantity of oil secreted is quite insufficient to smear the whole plumage of any bird. The actions of the creature, which are presumed to be the smearing itself with this unguent, are nothing more than the process of combing, and preening, and arranging its feathers. The rumpless Fowl has a coat just as glossy as any other variety. The necks of some birds, as Owls, are too short to reach the gland that is to supply the natural Macassar. In other birds, of most aquatic and even oceanic habits, the rump itself is but little developed. What function is performed by these glands, remains yet to be demonstrated: probably it will be found to be simply excretory. The question of lubrication might very soon be set at rest by amputating the rump of a common Duck or Goose (were such cruelty at all justifiable-which it is not), and if, at the end of a month, the mutilated creature swam as buoyantly as ever, it would certainly not be by the assistance of the oil-gland. I venture, therefore, to suggest and claim the credit of first suggesting-that this cause may probably be found in some minute structural peculiarity of the texture of the feather, which the microscope can alone reveal to us. In geology that instrument has afforded great and unexpected assistance. A thin slice of a fossil tree tells us whether it was a palm, or whether it grew like our oaks and beeches; a minute fragment of a tooth has indicated the nature of an extinct and gigantic reptile. Youatt, through its aid, discovered the mechanical cause of the felting property of wool; and it is not too much to hope that it may throw light on the reason why some feathers resist moisture, and others do not.

Now, two conditions necessary for the repulsion of water by small objects, are rigidity and smoothness. The fur of a Water-Rat, that would be proof against all damp while the creature was living, and the hairs remained rigid and elastic, would become sodden as soon as death ensued, and the coating became flaccid. "Insects which, like the Gnat, walk much upon the surface of water, have at the end of their feet a brush of fine hair, the dry points of which appear to repel the fluid, and prevent the leg from being wetted. If these brushes be moistened with spirit of wine, this apparent repulsion no longer takes place, and the insect immediately sinks, and is drowned."-Dr. Roget's Bridgewater Treatise, vol. i., p. 334. A hair that would sink if once wetted, will, if dropped gently on the surface, float by means of the air contained in the vacant space caused by its repulsion. The same will happen with a dry and polished needle of considerable size, although iron is so much heavier than water. If, then, it shall be found that the minute parts of waterproof feathers possess these qualities of smoothness and rigidity, in combination with others yet to be discovered, which qualities are not to be found in feathers that are easily wetted, a step will be gained which must lead to interesting results. We cannot hope to find out the ultimate cause of attraction and repulsion, any more than we can that of gravitation, but we may endeavour to learn the conditions of both.

Dr. Roget has discovered, by the microscope, a characteristic which distinguishes feathers intended for flight, from those whose use is for mere clothing or ornament. "The feathers of the Ostrich," he says,

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are unprovided with that elaborate apparatus of crotchets and fibres, which are universally met with in birds that fly." In those of the Peacock's tail this peculiar mechanism is deficient. We shall probably, at a future time, be equally able to point out the repulsive structure of feathers destined to be in constant contact with water, without being wetted by it.

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