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proper ones; where their young may lie safe and warin, and have their growth promoted. But then, with what an artificial elegance are some of their nests prepared? Human skill could hardly imitate it. Among other curiosities of nidification, I will mention one that is observed by pigeons of my own country. They build their nests with little sticks laid athwart one another, at such dis tances, that while they are so near together as to prevent the falling through of their eggs, they are yet so far asunder, that the cool air can come at their eggs. And the reason for this architecture of their nests is this; their bodies are much hotter than those of other birds; and their eggs would be perfectly addled by the heat of their bodies in the incubation, if the nests were not so built, that the cool air might come at them to temper it.

We have seen the nest of an Indian bird composed of the fibres of certain roots, which were so curiously interwoven, that it could not be seen without astonishment. These nests they hang on the ends of the twigs of the trees, over the water, to secure their eggs and young from the ravages of apes, and other beasts, that else would prey upon them. They are justly enough called subtle jacks.

What shall we say of the flamingos? They build their nests in shallow ponds, where there is much mud; which they scrape together into little hillocs, like islands, appearing out of the water about a foot and a half high from the bottom. They make the foundation of these hillocs broad, bringing them up tapering to the top, where they leave a small hollow pit, in which they lay their eggs; and when they either lay or hatch their

eggs, they stand all the while, not on the hilloc, but close by it, with their legs on the ground, and in the water, resting themselves on the hilloc, and covering the hollow nest upon it with their bodies. Their legs are very long, and building as they do upon the ground, they could neither draw their legs conveniently into their nests, nor sit down upon them otherwise than by resting their whole bodies to the prejudice of their eggs or young, were it not for this rare

contrivance.

The incubation, for which this tribe of animals is remarkable, opens a new scene of wonders. The egg with its crusty coat is admirably fitted for it. Here we find one part provided for the formation of the body before it is grown to any considerable dimensions, another for its nourishment afterwards till the bird be able to shift for itself. But then the accurate bracing of these parts, by which they are kept in their due place, must be a designed, as well as a curious piece of workmanship. They are separated by membranes.

The chalaza, (which because formerly thought the sperm of the cock was called the treddles,): are, as Harvey says, as it were the poles of this microcosm, and the connexions of the membranes. But as Mr. Derham observes, they serve only to keep one and the same part of the yolk always uppermost, let the egg be turned which way it will. The chalazæ, it seems, are specifically lighter than the whites in which they swim; and being braced to the membrane of the yolk, not exactly in the axis of the yolk, but somewhat out of it, it causes one side of the yolk to be heavier than the other: so that the yolk being by the chalazæ made buoyant, and kept swimming in

the midst of the two whites, is by its own heavy side kept with the same side always uppermost, and probably this uppermost side is that on which lies the cicatricula. It is affirmed, that our hens once in every day of their incubation turn their eggs, without ever turning of one more than once, or leaving any one unturned. This is for a service which they understand not themselves. The conveyance of what colours we please to the fowl that is hatching, by painting the eggs is a curiosity.

That birds must lay eggs, is a sensible argument of a divine Providence, designing to preserve them, and secure them, that there might be a greater plenty of them, and that the destroyers might not straiten their generations. Had they been viviparous, if they had brought forth a great number at a time, the burden of their womb would have rendered them so heavy, their wings could not well have served them: or if they had brought forth but one or two at a time, they would have been troubled all the year long with bearing or feeding their young. The conveniency consulted in oviparous animals, is one of Dr. More's triumphs over atheism. Of these eggs he makes an antidote against that hellish poison.

Dr. Cheyne will more particularly assure us, we know that the eggs of animals are only an uterus for a little animal, furnished with proper food, and fenced from external injuries: and we know likewise that all the effects of incubation are only to supply a proper degree of heat, which may make the congealed fluids to flow, and more easi ly pass into the nourishing channels of the included animalcule. On this occasion he goes on, we

are sure that all the transformations of insects and other animals, are nothing but the expansion of their parts, and the breaking of the membranes that folded them up, by the augmentation of those parts; and all the several figures they put on, are owing to the several membranes in which they are involved. His conclusion is what I was wishing for It is impossible duly to consider these things, without being wrapt into admiration of the infinite wisdom of the divine Architect, and contemning the arrogant production of chance and jostling atoms.

As Mr. Derham observes, what a prodigious instinct is it, that birds, and only they, should betake themselves to this way of generation! How should they be aware that their eggs contain their young, and that they have in their power the production of them? What should move them to betake themselves to the nests, and there with delight and patience abide the due number of days? And when their chickens are hatched, how surprising is their art, and care, and passion, in providing for them, until they are able to shirk for themselves.

A remark of Mr. Ray is worthy to be intro duced here. It would be on many accounts inconvenient for birds to give suck; and yet no less inconvenient, if not altogether destructive to the chicken, upon exclusion. all of a sudden, to make so great a change in its diet, as to pass from a liquid to a harder food, before the stomach be consolidated, and by use habituated to concocting it, and its tender and pappy flesh fitted to be nourished by what shall be strong and solid; and before the bird be by little and little accustomed

to using his bill in the gathering of it up, to which it comes not very readily therefore there is a large yolk provided in every egg, a great part of which remains after the chicken is hatched, and is inclosed in its belly, and by a channel made on purpose, received by degrees into the intestines, and serves instead of milk, to nourish the chicken for a considerable time; which nevertheless in the mean time feeds itself by the mouth, a little at a time, and gradually more and more, as it gets a more perfect ability.

I will add a curiosity relating to the pigeons, which annually visit my own country in their seasons, in such incredible numbers, that they have commonly been sold for two-pence a dozen; yea, one man has at one time surprised no less than two hundred dozen in his barn, into which they have come for food, and by shutting the door, he has caught them all. Among these pigeons the cocks take care of the young ones for one part of the day, and the hens for the other. When they are taken, we generally take but one sex at a time. In the crops of the cocks, we find about the quantity of half a gili of a substance like a tender cheese-curd the hens have it not. This curd flows naturally into their crops, as milk does into the dugs of others creatures. The hens

could not keep their young ones alive when first hatched; but the cocks fetch up this thickened milk, and throw it into the bills of their young ones, which are so nourished with it, that they grow faster, and fly sooner than any other bird among us. None but the cocks which have young ones to care for, have this curd found in their crops. Kill one of those cocks, and all the

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