Part 18
Among other instances of the preservation of animals, we ought to mention that of the pole-cat of America, commonly called the squash or skink. This is a small animal of the weasel kind, which some of the planters of that country keep about their premises to perform the office of a cat. This creature has always a very strong and disagreeable smell, but when affrighted or enraged, it emits so horrible a stench, as to prevent any other creature from approaching it: even dogs in pursuit of it, when they find this extraordinary mode of defence made use of, will instantly turn, and leave him undisputed master of the field; nor can any attempts ever bring them to rally again. Kalm, as quoted by Buffon, says, "One of these animals came near the farm where I lived in the year 1749. It was in the winter season, during the night; and the dogs that were upon the watch, pursued it for some time, until it discharged against them. Although I was in bed a good way off, I thought I should have been suffocated; and the cows and oxen themselves, by their lowings, shewed how much they were affected by the stench."
Nor is even the serpent, in its various kinds, destitute of the care of the common Father of nature. This reptile, which has neither wings to fly, nor the power to run with much speed, would not have the means to take its prey, were it not endowed with superior cunning to most other creatures. In favour of the serpent, also, there is a terror attending its appearance, which operates with such power upon birds and other small animals, as often to cause them to fall an easy prey to it. Hence, probably, has arisen the fiction of the power of fascination, which has been confidently ascribed to the rattlesnake and some other serpents.
On the DESTRUCTION OF ANIMALS.
In considering the destruction of animals, we may observe that Nature is continually operating: she produces, preserves for a time, and then destroys all her productions. Man himself is subject to this general order; for he also, like other creatures, returns to the dust from whence he was taken.
This process of nature is marked even in the vicissitudes of the seasons. Spring, like the jovial, playful infancy of all living creatures, represents childhood and youth; for then plants spread forth their flowers, fishes play in the waters, birds sing, and universal nature rejoices. Summer, like middle age, exhibits plants and trees full clothed in green; fruits ripen; and every thing is full of life. But autumn is comparatively gloomy; for then the leaves fall from the trees, and plants begin to wither, insects grow torpid, and many animals retire to their winter quarters.
The day proceeds with steps similar to the year. In the morning every thing is fresh and playful; at noon all is energy and action; evening follows, and every thing is inert and sluggish.
Thus the age of man begins from the cradle; pleasing childhood succeeds; then sprightly youth; afterwards manhood, firm, severe, and intent on self-preservation; lastly, old age creeps on, debilitates, and, at length, totally destroys our tottering bodies.
But we must consider the destruction of animals more at large. We have before observed, that all animals do not live on vegetables, but there are some which feed on animalcula; others on insects. Nay, some there are which subsist only by rapine, and daily destroy some or other of the peaceable kind.
The destruction of animals by each other, is generally in progression,--the strong prevailing against the weak. Thus, the tree-louse lives on plants; the fly called musca amphidivora, lives on the tree-louse; the hornet and wasp-fly, on the musca amphidivora; the dragon-fly, on the hornet and wasp-fly; the larger spider, on the dragon-fly; small birds feed on the spider; and lastly, the hawk kind on the small birds.
In like manner, the monoculus delights in putrid waters; the gnat eats the monoculus; the frog eats the gnat; the pike eats the frog; and the sea-calf eats the pike.
The bat and the goat-sucker make their excursions only at night, that they may catch the moths, which at that time fly about in great quantities.
The woodpecker pulls out the insects which lie hid in the trunks of trees. The swallow pursues those which fly about in the open air. The mole feeds on worms and grubs in the earth. The large fishes devour the small ones. And perhaps there is not an animal in existence, which has not an enemy to contend with.
Among quadrupeds, wild beasts are most remarkably pernicious and dangerous to others. But that they may not, by their cruelty, destroy a whole species, these are circumscribed within certain bounds: as to the fiercest of them, they are few in number, when compared with other animals; sometimes they fall upon and destroy each other; and it is remarked also, that they seldom live to a great age, for they are subject, from the nature of their diet, to various diseases, which bring them sooner to an end than those animals which live on vegetables. It has been asked, why has the Supreme Being constituted such an order in nature, that, it should seem, some animals are created only to be destroyed by others? To this it has been answered, that Providence not only aimed at sustaining, but also keeping a just proportion amongst all the species, and so preventing any one of them from increasing too much, to the detriment of men and other animals. For if it be true, as it assuredly is, that the surface of the earth can support only a certain number of creatures, they must all perish, if the same number were doubled or trebled.
There are many kinds of flies, which bring forth so abundantly, that they would soon fill the air, and, like clouds, intercept the light of the sun, unless they were devoured by birds, spiders, and other animals.
Storks and cranes free Egypt from frogs, which, after the inundation of the Nile, cover the whole country. Falcons clear Palestine from mice. Bellonius, on this subject, says, "The storks come to Egypt in such abundance, that the fields and meadows are quite white with them. Yet the Egyptians are not displeased with them, as frogs are generated in such numbers, that, did not the storks devour them, they would over-run every thing. Besides, they also catch and eat serpents. Between Belba and Gaza, the fields of Palestine are often injured by mice and rats; and were these vermin not destroyed by the falcons, that come here by instinct, the inhabitants could have no harvest."
The white fox is of equal advantage in the Lapland Alps; as he destroys the Norway rat, which, by its prodigious increase, would otherwise entirely destroy vegetation in that country.
It is sufficient for us to believe that Providence is wise in all its works, and that nothing is made in vain. When rapacious animals do us mischief, let us not think that the Creator planned the order of nature according to our private principles of economy; for the Laplander has one way of living, the European husbandman another, and the Hottentot differs from them both; whereas the stupendous Deity is one throughout the globe; and if Providence do not always calculate according to our method of reckoning, we ought to consider this affair in the same light as when different seamen wait for a fair wind, every one with respect to the port to which he is bound: these we plainly see cannot all be satisfied.
We shall conclude this branch, by turning once more to Man, and tracing him through his progressive stages of decay, until death puts a final period to his earthly existence.
The human form has no sooner arrived at its state of perfection, than it begins to decline. The alteration is at first insensible, and often several years are elapsed before we find ourselves grown old. The news of this unwelcome change too generally comes from without; and we learn from others that we grow old, before we are willing to believe the report.
When the body is come to its full height, and is extended into its just dimensions, it then also begins to receive an additional bulk, which rather loads than assists it. This is formed of fat, which, generally, at about the age of forty, covers all the muscles, and interrupts their activity. Every exertion is then performed with greater labour, and the increase of size only serves as the forerunner of decay.
The bones also become every day more solid. In the embryo they are almost as soft as the muscles and the flesh, but by degrees they harden, and acquire their proper vigour; but still, for the purpose of circulation, they are furnished through all their substance with their proper canals. Nevertheless, these canals are of very different capacities during the different stages of life. In infancy they are capacious, and the blood flows almost as freely through the bones as through any other part of the body; in manhood their size is greatly diminished, the vessels are almost imperceptible, and the circulation is proportionably slow. But in the decline of life, the blood which flows through the bones, no longer contributing to their growth, must necessarily serve to increase their hardness. The channels which run through the human frame may be compared to those pipes that we see crusted on the inside, by the water, for a long continuance, running through them. Both every day grow less and less, by the small rigid particles which are deposited within them. Thus, as the vessels are by degrees diminished, the juices also, which circulate through them, are diminished in proportion; till at length, in old age, these props of the human frame are not only more solid, but more brittle.
The cartilages, likewise, grow more rigid; the juices circulating through them, every day contribute to make them harder, so that those parts which in youth are elastic and pliant, in age become hard and bony, consequently the motion of the joints must become more difficult. Thus, in old age, every action of the body is performed with labour, and the cartilages, formerly so supple, will now sooner break than bend.
As the cartilages acquire hardness, and unfit the joints for motion, so also that mucous liquor, which is always secreted between the joints, and which serves, like oil to a hinge, to give them an easy and ready play, is now grown more scanty. It becomes thicker and more clammy, more unfit for answering the purposes of motion, and from thence, in old age every joint is stiff and awkward. At every motion this clammy liquor is heard to crack; and it is not without a great effort of the muscles, that its resistance is overcome. Old persons have been known, that seldom moved a single joint without thus giving notice of the violence that was done to it.
The membranes that cover the bones, joints, and the rest of the body, become, as we grow old, more dense and more dry. Those which surround the bones soon cease to be ductile. The fibres, of which the muscles or flesh is composed, become every day more rigid; and while, to the touch, the body seems, as we advance in years, to grow softer, it is in reality increasing in hardness. It is the skin, and not the flesh, that we feel on such occasions. The fat, and the flabbiness of it, seem to give an appearance of softness, which the flesh itself is very far from having. None can doubt this after trying the difference between the flesh of young and old animals. The first is soft and tender, the last is hard and dry.
The skin is the only part of the body that age does not harden; that stretches to every degree of tension; and we have often frightful instances of its pliancy, in many disorders which are incident to humanity. In youth, while the body is vigorous and increasing, it continues to give way to its growth. But although it thus adapts itself to our increase, its does not in the same manner conform to our decay. The skin, in youth and health, is plump, glossy, veined, and clear; but when the body begins to decline, it has not elasticity enough to shrink entirely with its diminution; it becomes dark or yellow, and hangs in wrinkles, which no cosmetic can remove. The wrinkles of the body in general proceed from this cause; but those of the face seem to proceed from another, namely, from that variety of positions into which it is put by the speech, the food, or the passions. Every grimace, every passion, and every gratification of appetite, puts the visage into different forms. These are visible enough in young persons; but what at first was accidental or transitory, becomes, by habit, unalterably fixed in the visage as it grows older.
Hence, as we advance in age, the bones, the cartilages, the membranes, the flesh, and every fibre of the body, becomes more solid, more dry, and more brittle. Every part shrinks, motion becomes more slow, the circulation of the 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 nourishment. 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 proper nourishment. 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 worm, contains in itself, as the bud does the rudiments of a tree, all the viscera necessary to the animal. The parts essential to life are distributed throughout the body, 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.
CHAP. XIII.
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 In one beneficent, one vast design; E'en from inanimates to breathing man,-- A heaven-conceiv'd, heaven-executed plan; Onward, from those who soar or lowly creep, The wholesome equipoise through all to keep, As faithful agents in earth, sea, and air, The lower world to watch with constant care; Her due proportion wisely to conserve:-- A wondrous trust, from which they never swerve. _Pratt._
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 for 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 some water, and proceed to the formation of their establishment. 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 effected 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 itself.