NATURAL HISTORY. The objects of nature may be considered under two points of view; first, with respect to their form, structure, habits, and individual properties, when viewed in a state of inactivity; and secondly, with respect to the mutual changes which they produce when made to act upon each other. Hence the study of nature may be divided into two parts, namely, Natural History and Natural Science; the former considering bodies in comparatively an inactive state, and the latter in a state of mutual action.

Natural History, then, is that part of natural knowledge which teaches us to distinguish and describe the objects of nature; to examine their appearance, structure, properties, and uses; and to collect, preserve, and arrange them.^[1. Some writers divide natural history into general and particular, which have been accurately defined by Cuvier. General natural history considers, under a single point of view, all natural bodies, and the common result of all their actions in the great whole of nature. It determines the laws of the co-existence of their properties; it establishes the degrees of resemblance which exist between different bodies; and it classes them according to these degrees. The Particular natural history of any body, to be perfect, should comprehend, first, the description of all the sensible properties of that body, and of all its parts; secondly, the mutual relations of these parts, the motions which they produce, and the changes which they undergo whilst they remain united; thirdly, the active and passive relations of this body with every other body in the universe; and, fourthly, the explanation of all these phenomena. (See Tableau Elémentaire d’Histoire Naturelle.} ]

I. When we take a general survey of the objects with which we are surrounded, we are bewildered amidst the number and the variety which are everywhere presented to our view. The air, the woods, the fields, and the waters, teem with myriads of animals; a large proportion of the earth’s surface is covered with a green mantle of luxuriant herbage, interspersed with plants and flowers of a thousand varied tints; and when we search below this, or when we explore the cloud-capt mountain, the gloomy mine, the sequestered cavern, or the rocky cliff, we discover a great variety of mineral substances, either piled into irregular masses, or lying in uniform beds or layers, disposed in veins or seams, or scattered at random through the other stony matters.

To the casual observer, the number and variety of these objects would appear almost infinite, and he would consider it as impossible to enumerate them as to number the stars or count the sands on the sea-shore. This idea, however, arises from his seeing them lying in confusion and disorder. The naturalist, by separating them into those groups or classes in which they often naturally present themselves, has succeeded not only in distinguishing the several kinds from each other, but even in guessing pretty accurately at the number of species which have hitherto been discovered. In fact, there are two objects which should principally occupy the attention of the naturalist; first, to classify natural substances; secondly, to examine their structure.

The number of natural productions being confessedly very great, it is necessary to find out some means of distinguishing them from each other, and of recognising them on seeing them anew. These means are the peculiarities, or the assemblages of peculiarities, which belong exclusively to each body. Now there is scarcely any substance which has a simple character, that is, which can be distinguished from every other substance by any one of its properties singly. It is only by the combination of several of these properties that we can distinguish an object from others which resemble it in possessing some one or more of those very properties; and the more numerous the species we compare, the more necessary it becomes to bring their properties together, in order to assign to each a character that may distinguish it from the rest. Hence, to distinguish a species, considered independently of all others that exist in nature, it is necessary to express in its character almost the whole of its properties; and the greater the number of these we take into the character, the more complete will be our description of the object. But no man can acquire a sufficiently accurate knowledge of all natural objects to enable him to give a complete description of them. Human life is too short to admit of the completion of such a task. All that can be expected from our limited faculties, is to acquire a general knowledge of natural objects, confining our principal attention to such as possess some striking qualities, or appear convertible to the useful purposes of life.

To attain this end, two modes of procedure have been adopted by naturalists. According to the first mode, characters are employed which rise by degrees from particulars to generals. They begin by comparing together a certain number of species which bear the nearest relation to each other. In drawing the characters of these species, it is requisite to express only those differences which, on a supposition that they are the most nearly related, form but a small part of their properties; and a number of species thus brought together constitutes what is denominated a genus or tribe.

The remainder of those properties which are common to all the species of the genus combine to form the character, or rather the description, of the genus, distinguishing it from all those which might be formed by bringing together other species; but the number of such common properties being still very considerable, the same means [7:15:739]are repeated, in order to reduce the characters of the genera to smaller terms. We compare together only those genera which most nearly resemble each other; and the generic characters now employed must only express those differences which form but a small part of their common properties. The properties which are common to all the genera compose a character which distinguishes this assemblage or group from all other groups of genera. Such an assemblage of genera is called an order.

Repeating the same operation, and bringing together such orders as are most nearly allied, we form a more general assemblage, called a class ; and again uniting a certain number of classes, we form a higher division, to which naturalists have given the name of Kingdom. This chain of divisions, in which the higher links comprehend the lower, forms what is called a method.

The other mode of procedure is to proceed gradually from generals to particulars, beginning with the slightest and most obvious differences, thus forming the first division or kingdom; dividing each kingdom into classes, each class into orders, each order into genera, each genus into species, and each species into varieties. This descending series constitutes what is called a system, and is that which has been generally adopted by naturalists.

In order to illustrate this systematical classification of natural objects, let us select a familiar example. Amongst the various creatures which pass under our observation, a great number are possessed of life, of sensation, and voluntary motion. These we call animals, and of them we form the animal kingdom. On examining various groups of animals, we find that many have four extremities, and suckle their young by means of teats, and these we call quadrupeds or mammalia, thus forming a class of animals. Again we find, that of the mammalia some have hoofed feet and blunt fore-teeth, and feed almost entirely on vegetables. These constitute an order of the class of mammalia, to which Linnaeus has given the name of belluae. Of this order a certain number of animals agree in having six fore-teeth in both jaws, and form a genus or tribe distinguished by this particular from the other animals of the same order, and commonly called the horse tribe. Lastly, in this tribe we find one species which has solid hoofs, a tail bristly at the end, an upright mane, and a black cross on the shoulder of the male. This species is the common ass.

In framing an artificial system of natural history, most writers have agreed on the division of natural bodies into kingdoms, proceeding on the supposition that those marks which are to distinguish the objects of one kingdom from those of another are sufficiently fixed and certain. Let us examine for a little how far this supposition agrees with nature’s works as we find them.

The division of natural objects commonly adopted is into three kingdoms; the animal, vegetable, and mineral. This division has been almost universally received as perfectly consistent with nature, and is by most persons conceived to be so clear and distinct, that they suppose it impossible to mistake in referring any particular object to its proper kingdom. This arises from their having noticed only such objects as bear evident marks of the division to which they belong; but if we draw their attention to a variety of other individuals, they will acknowledge themselves to be incompetent to the decision, or will erroneously refer to one division, what has, after accurate examination, been determined to belong to another.

There is one whole class of productions, called zoophytes by naturalists, which appear to form the connecting links between the different kingdoms. They are animals of the polypus kind, mostly covered with a calcareous crust, differing little in composition from the shells of lobsters, shrimps, and other shell-fish, and formed, like them, from an exudation or secretion on the surface of their bodies.

These polypi are connected together by thousands, or even millions, and assume a great variety of appearances, according to their arrangement; the same species, however, always assuming the same, or very nearly the same, appearance. Some are connected together in the form of stem and branches, as the fiustrae, sertulariae, corallines, and others, many of which have their offspring in the egg state attached to them, and so situated as to bear exact resemblance to the seed-vessels of plants. These are altogether so like to many of the sea-plants, as to be generally confounded with them under the title of sea-weeds; but the attentive observer may, by examining them in their natural state, perceive the tentacula or feelers of each polypus extended in its search for food, and hastily retracting within its shell upon the least alarm. Many of this description are found attached to oysters or other shell-fish, and often to stones and pebbles which are covered or occasionally wetted by the sea.

Other zoophytes assume less regular figures, and are much more firm and solid, resembling the productions of the mineral kingdom. Madrepores and millepores, called often brainstones, are of this kind. At first sight they look very like stones and pebbles, or like pieces of chalk or marble; but on an accurate inspection, any one may perceive marks of an organic structure, and, when they are in a recent state, may detect the inhabitants of their numerous cells.

The above examples will perhaps suffice to prove how insufficient is either a'hasty examination, or the judging by similarity of appearance, for determining to what kingdom of nature any particular object belongs. But there are many other productions to which few persons could, without hesitation, assign their places. For instance, where would we arrange the green powdery substance so common on paling; the spotted and streaked appearance on stones; the mould on cheese, or the green jelly-like matter which floats on the surface of the stagnant waters? Naturalists in general have assigned these productions to the vegetable kingdom; but Sennebier and a few others have maintained that some of them are animals.

According to some writers, the most philosophical notion which we can form on this subject is, that the division of natural objects into kingdoms is artificial, and that nature, acknowledging no such bonds, passes imperceptibly from the animal to the vegetable, and from the vegetable to the mineral world, without defining where the one ceases or where the next begins.

As the appearances of natural productions are insufficient, so are their properties and powers, for determining which are animals or which vegetables, according to the received acceptation of the terms. If locomotion is allowed to be the characteristic of an animal, where shall we place the oyster, or the zoophytes of which we have just been speaking, or where some species of ulva and conferva, plants that swim about detached in water? If feeling or sensation be the test, who shall decide that the sensitive plant (mimosa pudica) possesses it not? and who determine that the leaves of the fly-trap (dionaea muscipula), when they contract, and catch the fly as soon as it alights, do not feel the despoiler that comes to rob it of its honey? Though these and similar objections may certainly be made to the artificial division of nature’s works into kingdoms, yet it is convenient to have such a division; and even the very difficulty of establishing to which kingdom any object belongs is an additional spur to the genius and industry of the naturalist.

The most natural division of the works of nature is that which distinguishes them into organized and inorganic bodies; and, on the whole, we have seen no attempt to establish the differences between these so successful as that adopted by Μ. Dumeril in his Traité Elémentaire [7:15:740](THistoire Naturelle. “Some objects,” says he, “as animals and plants, have formerly constituted a part of other individuals, similar to themselves, from which they have been separated at a certain period, under the form of eggs, of germs, or of little living creatures; and their existence is evidently owing to this generation; they are born. Others, on the contrary, as stones, salts, water, may be formed by certain circumstances, and even by ourselves at pleasure. They have not necessarily made a part of other similar bodies; their existence seems to depend on certain fortuitous circumstances, that have produced the approximation of their constituent principles, and their origin might be referred to attraction. These bodies are formed. Vegetables and animals, in increasing their size, only develope themselves. Whatever may be their minuteness, we shall, on a careful examination, find them already formed, with their parts requiring only to be evolved. Their increase proceeds from within outwards, by intussusception. Stones, and a great many other bodies, are augmented only by the same matter from which they are produced; their growth takes place always from without, by a sort of aggregation.

“As the increase of the bodies which compose these two great subdivisions is not alike in both, a duration very different ought to be the result of these dissimilarities. In fact, minerals are susceptible of indefinite increase, and their end is always indeterminate; it is vague, and depends on the circumstances under which they are placed. Plants and animals ought, from the same circumstances which favoured their development, to stop when their extension has been carried to the highest degree, so that the end or death of these bodies is fixed and necessary.

“The masses in which stones and other similar bodies generally present themselves are angular, insulated, and very variable in their size. The individuals which we call plants and animals have always, and necessarily, a form that is constant, for the most part rounded and symmetrical, and their extension is limited within certain bounds.

“There is this great difference between these bodies, that those which increase by aggregation may be divided into molecules, or parts infinitely small, bearing a very near resemblance to the mass from which they were taken; while in those which develope themselves, no portion can be taken away and exist by itself, at least unless it develope new parts, which replace those that are wanting.

“The bodies which do not develope themselves are in general formed of fluids or solids which remain constantly in the same points; they are composed of very few elements, which may be separated and again reunited. The bodies which develope themselves, on the contrary, are essentially composed of solids and fluids, which are always changing, and in a state of renovation; they have always, and from necessity, more or less consistence; they are penetrated and augmented by fluids; and after being decomposed, they can never be formed again such as they were before.”

For the more convenient study of natural history, the whole subject may be divided into five great branches, namely, meteorology, hydrography, mineralogy,botany, and zoology. Meteorology includes the description of all those phenomena which take place in the atmosphere that surrounds the terrestrial globe. See the article Meteorology. Hydrography comprehends the natural history of the sea, of rivers, lakes, and other collections of water that make up so large a part of the earth. See the article Physical Geography. Mineralogy is that part of the subject which treats of the solid inorganic bodies that are found on the surface or in the bowels of the earth. See the article Mineralogy. Botany comprehends the natural history of vegetables. See the article Botany. And zoology includes the natural history of all animated beings, and is subdivided into many subordinate classes. The classification followed in this work is fully explained in the article Animal, where also the reader will find a view of all the other systems.

It is not surprising that naturalists of taste and genius, observing the gradation which seems to take place amongst the works of nature, should have been led to form the notion that there exists a regular series or chain of beings, the links of which, if we could discover them all, would be found to resemble each other so nearly, as only to exhibit to the superficial observer a few shades of difference. Natura non per saltum movet, has become a sort of axiom in natural history.

The notion of a chain of being is alluring, and does not want arguments in its favour. The Esquimaux Indian, or the inhabitant of Terra del Fuego, seems scarcely superior in form, and very little in intellect, to the oran-utang; the platypus, the flying lemur, flying squirrels, and, still more, the bats, appear to form the connecting links between quadrupeds and birds; while the seals, the walrusses, and the whole order of cete, connect the former with the fishes. In this latter class, the flying fish, in its capability of supporting itself in the air, seems to approach the feathered tribes; while some of these, as the penguins, in their habits and manner of life bear some distant resemblance to fishes. Again, the siren and the eels so nearly resemble each other, that it has been disputed whether the former should be reckoned among the amphibia or the fishes ; whilst one species of lizard (lacerta lumbricodes) is so like an earthworm, as apparently to connect the amphibia and the vermes. Farther, the diminutive humming-bird (trochilus exilis) and the humble-bee (apis terrestris) are so nearly alike, both in size and manner of life, as to form no very exceptionable links of union between the birds and the insects.

If, again, we compare the vegetable tribes with some of the inferior classes of animals, we shall perceive many points of resemblance, which may seem to indicate a continuance of the same chain. Besides the mimosa pudica and dionaea muscipula, already mentioned, the hedysarum gyrans or moving plant is a remarkable instance of the mobility of vegetables; the carrion flower (stapelia hirsuta), and some species of morel, bear the odour of putrid animal substances; while, on the other hand, the mantis siccifolia might be mistaken for a dried leaf; several species of pennatula (sea pens) and sertularia, for ferns; the madrepora fun-gites (mushroom madrepore), for a petrified mushroom; and the tubularia magnifica and actiniae, when expanded, for the most beautiful full-blown flowers.

Lastly, on comparing the mineral kingdom with the classes of organized beings, we find several so nearly resembling stones, as scarcely to be distinguished from them.

But although the view which we have given above, of the circumstances that have led naturalists to form the idea of a regular chain of beings, is specious, it will not bear the scrutiny of a strict examination. The resemblances which we have pointed out are more apparent than real; and anatomy and chemistry, added to a more accurate acquaintance with the works of nature, have proved that those links which, to superficial observers, appear most allied, arc yet separated by considerable chasms. In fact, if we were to admit these resemblances as ever so accurate, they would lead us to form, not one chain, but many.