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motion becomes more slow, the circulation of tle fluids is performed with less freedom; perspiration diminishes; the secretions alter, the digestion becomes laborious; and the juices no longer serve to convey their accustomed nourish-nent. Thus the body dies by little and little, and all its functions are diminished by degrees; life is driven from one part of the frame to another; universal rigidity prevails; and death, at last, seizes upon the remnant that is left.
As the bones. the cartilages, the muscles, and all other parts of the body, are softer in women than in men, these parts must, of consequence, require a longer time to arrive at that state of hardness which occasions death. Women, therefore, ought to be longer in growing old than men, and this is, generally speaking, the case. If we consult the tables which have been drawn up respecting human life, we shall find that, after a certain age, they are more long-lived than men, all other circumstances the same. Thus a woman of sixty has a greater probability, than a man of the same age, of living till eighty.
We shall close this chapter with an account of ANIMAL REPRODUCTIONS..
Here we discover a new field of wonders, that seems entirely to contradict the principles that we had adopted concerning the formation of organized bodies. It was long thought that animals could only be multiplied by eggs, or by young ones. But it is now found that there are some exceptions to this general rule, since certain animal bodies have been discovered, that may be divided into as many complete bodies as you please; for each part thus separated from the parent body, soon repairs what is deficient, and becomes a complete animal. It is now no longer doubtful that the polypus belongs to the class of animals, though it much resembles plants, both in form, and in its mode of propagating. The bodies of these creatures may be either cut across or longitudinally, and the pieces will become so many complete polypi. Even from the skin, or least part, cut off from the body, one or more polypi will be produced; and if several pieces cut off be joined together by the extremities, they will perfectly unite, nourish each other, and become one body. This discovery has given rise to other experiments, and it has been found that polypi are not the only animals which live and grow after being cut in pieces. The earth-worm will multiply after being cut in two; to the tail there grows a head, and the two pieces then become two worms. After having been divided, they cannot be joined together again; they remain for some time in the same state, or grow rather smaller; we then see at the extremity which was cut, a little white button begin to appear, which increases
and gradually lengthens. Soon after, we may observe rings at first very close together, but insensibly extending on all sides; a new stomach, and other organs, are then formed. We may at any time make the following experiment with. snails cut off their heads close by the horns, and in a certain space of time the head will be reproduced. A similar circumstance takes place in crabs; if one of their claws is torn off, it will again be entirely reproduced.
A very remarkable experiment was made by Duhamel, on the thigh of a chicken. After the thigh-bone which had been broken was perfectly restored, and a callus completely formed, he stripped off the flesh down to the bone; the parts were gradually reproduced, and the bone, and the circulation. of the blood, again renewed. We know then that some animals may be multiplied by dividing them into pieces; and we no longer doubt that the young of certain insects may be produced in the same manner as a branch is from a tree; that, being cut in pieces, they will live again in the smallest piece; that they may be turned inside out like a glove, divided into pieces, then turned again, and yet live, eat, grow, and multiply. Here a question offers itself, which perhaps no naturalist can resolve in a satisfactory manner: How does it happen that the parts thus cut off, can be again reproduced? We must suppose that germs are distributed to every part of the body; whilst in other animals they are only contained in certain parts. These germs unfold themselves when they receive profern ourishment. Thus, when an animal is cut in pieces, the germ is supplied with the necessary juices, which would have been conveyed to other parts, if they had not been diverted into a different channel. The superfluous juices develop those parts which without them would have continued attached to each other. Every part of the polypus and w contains in itself, as the bud does the rudiments of a tree, all the viscera necessary to the anima' The parts essential to life are distributed throughout the pouy, and the circulation is carried on even in the smallest particles. As we do not understand all the means that the Author of nature makes use of to distribute life and feeling to such a number of animals, we have no reason to maintain, that the creatures of which we have been speaking, are the only ones that are exceptions to the general rule in their mode of propagating. The fecundity of nature, and the infinite wisdom of the Creator, always surpass our feeble conceptions. The same hand that has formed the polypus and the worm, has shewn us that it is able to simplify the structure of animals
CURIOSITIES RESPECTING ANIMALS.-(Continued.)
The Beaver, and its Habitations-The Mole-The Frog-The Toad-The Rhinoceros-Crocodiles and Alligators-Fossil Crocodile-The Ornithorhynchus Paradoxus-The Marmot, or Mountain Rat, of Switzerland.
Nature's unnumber'd family combine
The lower world to watch with constant care;
IT would not be consistent with the plan of this work to embrace the whole natural history of the animal and vegetable kingdom. This is a Book of Curiosities; and it is our intention to present the reader with a sketch of the most remarkable things in the universe: our present subject, therefore, being curiosities respecting animals, we shall commence with
THE BEAVER.-This animal was known to the ancients fo its possession of that sebaceous matter called castor, secreted by two large glands near its genitals and anus, and of which each animal has about two ounces; but they appear to have been unacquainted with its habits and economy, with that mental contrivance and practical dexterity, which in its natural state so strikingly distinguish it. Beavers are found in the most northern latitudes of Europe and Asia, but are most abundant in North America.
In the months of June and July, they assemble in large companies to the number of two hundred, on the banks of sɔme water, and proceed to the formation of their establish ment. If the water be subject to risings and fallings, they erect a dam, to preserve it at a constant level; where this level is naturally preserved, this labour is superseded. The length of this dam is occasionally eight feet. In the preparation of it, they begin with felling some very high, but not extremely thick tree, on the border of a river, which can be made to fall into the water; and, in a short time, this is et fected by the united operation of many, with their fore-teeth, the branches being afterwards cleared by the same process A multitude of smaller trees are found necessary to complete
the fabric, and many of these are dragged from some distance by land, and formed into stakes; the fixing of which is a work of extreme difficulty and perseverance, some of the beavers with their teeth raising their large ends against the crossbeam, while others at the bottom dig with their fore-feet the holes in which the points are to be sunk. A series of these stakes, in several rows, is established from one bank of the river to the other, in connection with the cross-tree, and the intervals between them are filled up by vast quantities of earth, brought from a distance, and plashed with materials adapted to give it tenacity, and prevent its being carried off. The bark is formed at the bottom, of about the width of twelve feet, diminishing as it approaches the surface of the water, to two or three; being thus judiciously constructed to resist its weight and efforts by the inclined plane instead of perpendicular opposition.
These preparations, of such immense magnitude and toil, being completed, they proceed to the construction of their mansions, which are raised on piles near the margin of the stream or lake, and have one opening from the land, and another by which they have instant access to the water. These buildings are usually of an orbicular form, in general about the diameter of ten feet, and comprehending frequently several stories. The foundation walls are nearly two feet in thickness, resting upon planks or stakes, which constitute also their floors. In the houses of one story only, the walls, which in all cases are plastered with extreme neatness both externally and within, after rising about two feet perpendicularly, approach each other, so as at length to constitute, in closing, a species of dome. In the application of the mortar to their habitations, the tails as well as feet of the beavers are of essential service. Stone, wood, and a sandy kind of earth, are employed in their structures, which, by their compactness and strength, completely preclude injury from winds and rain. The alder, poplar, and willow, are the principal trees which they employ; and they always begin their operations on the trunk, at nearly two feet above the ground; nor do they ever desist from the process till its fall is completed. They sit instead of stand, at this labour, and while reducing the tree to the ground, derive a pleasure at once from the success of their toils, and from the gratification of their palate and appetite by the bark, which is a favourite species of food to them, as well as the young and tender parts of the wood tself.
For their support in winter, ample stores are laid up near each separate cabin; and occasionally, to give variety and luxury to their repasts during a long season, in which their stores must have become dry and nearly tasteless, they will
make excursions into the neighbouring woods for fresh sup plies. Depredations by the tenants of one cabin on the magazines of another are unknown, and the strictest notions of property and honesty are universal. Some of their habitations will contain six only, others twelve, and some even twenty or thirty inhabitants; and the whole village or township contains in general about twelve or fourteen habitations. Strangers are not permitted to intrude on the vicinity; but, amidst the different members of the society itself, there appears to prevail that attachment and that friendship which are the natural result of mutual co-operation, and of active and successful struggles against difficulty. The approach of danger is announced by the violent striking of their tails against the surface of the water, which extends the alarm to a great distance; and, while some throw themselves for security into the water, others re tire within the precincts of their cabins, where they are safe from every enemy but man.
The neatness as well as the security of their dwellings is remarkable, the floors being strewed over with box and fir, and displaying the most admirable cleanness and order. Their general position is that of sitting, the upper part of the body, with the head, being considerably raised, while the lower touches, and is somewhat indeed immersed in, the water. This element is not only indispensable to them in the same way as to other quadrupeds, but they carefully preserve access to it even when the ice is of very considerable depth, for the purpose of regaling themselves by excursions to a great extent under the frozen surface. The most general method of taking them is by attacking their cabins during these rambles, and watching their approach to a hole dug in the ice at a small distance, to which they are obliged, after a certain time, to resort for respiration.
If a man, who had never been informed of the industry of beavers and their manner of building, were shewn the edifices that they construct, he would suppose them to be the work of most eminent architects. Every thing is wonderful in the labours of these amphibious animals; the regular plan, the size, the solidity, and the admirable art of these buildings, must fill every attentive observer with astonishment.
The works of beavers have a great resemblance to those of men; and upon their first appearance we may imagine them to be produced by rational and thinking beings; but when we examine them nearer, we shall find that in all their proceedings, these animals do not act upon the principles of reason, but by an instinct which is implanted in them by nature. If reason guided their labours, we should naturally conclude that the buildings which they now construct would be very different from those they formerly made, and that they would gra