cases in which the philosopher has more to admire than the common observer. Every feather is a mechanical wonder. If we look at the quill, we find properties not easily brought together-strength and lightness. I know few things more remarkable than the strength and lightness of the very pen with which I am writing. If we cast our eye to the upper part of the stem, we see a material, made for the purpose, used in no other class of animals, and in no other part of birds; tough, light, pliant, and elastic. The pith, also, which feeds the feathers is, amongst animal substances, sui generis; neither bone, flesh, membrane, nor tendon. But the artificial part of a feather is the beard, or, as it is sometimes, I believe, called, the vane. By the beards are meant what are fastened on each side of the stem, and what constitute the breadth of the feather; what we usually strip off from one side or both when we make a pen. The separate pieces, or lamine, of which the beard is composed are called threads, sometimes filaments or rays. Now the first thing which an attentive observer will remark is, how much stronger the beard of the feather shows itself to be, when pressed in a direction perpendicular to its plane, than when rubbed, either up or down, in the line of the stem; and he will soon discover the structure which occasions this difference-namely, that the lamina whereof these beards are composed are flat, and placed with their flat sides towards each other; by which means, whilst they easily bend for the approaching of each other, as any one may they are harder to bend out of their plane, which is the direction in which they have to encounter the impulse and pressure of the air, and in which their strength is wanted, and put to the trial. all the entrails, so as to keep them constantly surrounded with air, and similar prolongations extending also into the cavity of their bones, serving to inflate these in the same manner-are not these peculiarities for the obvious purpose of giving lightness to the animal, and thus enabling it to support itself in the air?and does not this palpable subserviency of one part of the structure of birds to the rest, irresistibly inculcate the truth that one master-hand has regulated the whole? In the beaks or bills of birds, various as are their forms, we can trace an exact adaptation to the food of the species. In those that tear their prey, as the eagle and hawk-or bruise hard fruits, as the parrot-or penetrate the bark of trees, as the woodpecker-the bills are of extraordinary hardness, and, in form, intimately connected with the habits of the animal. In those to whom a sense of feeling in this part is necessary to enable them to find their food in mud or water, as the duck, it is very soft, generally flattened, and so constructed that fluids may filter through it, while the solid food is retained. A bill hooked at the end, with sharp edges, characterises birds of prey. Another species of strong sharp-edged bill, of an elongated shape, but without a hook, serves to cut and break, but not to tear; and this is the form of the bill in birds which live upon animals which make resistance in the water; some of these are straight, as in the heron-others curved, some downwards, some upwards. Some sharp-edged bills have their sides approximating, like the blade of a knife to its handle, and thus adapted to seize small sub-perceive by drawing his finger ever so lightly upwards, stances; as the penguin. The small, conical, arched bill of poultry serves only to take up grain. The bills of the smaller birds present all the varieties of the conical form, from the broad-based cone of the hawfinch to the thread-like cone of the humming-bird. Such of them as have strong short bills live on grain; those with long thin ones, on insects. Where the bill is short, flat, opening very anteriorly, as in martens and swallows, the bird seizes flies and butterflies in the air; and if it be long and curved, possessing some strength, we find it grubs up worms for its food. The same evidence of design which we discover in the bills of birds adapt-force; that nevertheless there is no glutinous cohesion ing them to procure the kind of food on which the individual is to subsist, is apparent also in the conformation of their digestive organs. As the food of birds varies from the softest animal matter to the hardest grain, so we observe every gradation in the structure of their stomachs, from the membranous sac of the carnivorous tribes to the true muscular gizzard of granivorous birds -varying according as the food consists of animal or vegetable materials, or presents more or less resistance from the cohesion of its texture. a This is one particularity in the structure of a feather: second is still more extraordinary. Whoever examines a feather, cannot help taking notice that the threads, or lamina, of which we have been speaking, in their natural state unite; that their union is something more than the mere apposition of loose surfaces; that they are not parted asunder without some degree of between them; that therefore, by some mechanical means or other, they catch or clasp among themselves, thereby giving to the beard, or vane, its closeness and compactness of texture. Nor is this all when two lamine which have been separated by accident or force are brought together again, they immediately reclasp: the connection, whatever it was, is perfectly recovered, and the beard of the feather becomes as smooth and firm as if nothing had happened to it. Draw your finger down the feather, which is against the grain, and you In no branch of natural history do we find more re-break, probably, the junction of some of the contiguous markable evidences of design than in the varieties of threads; draw your finger up the feather, and you kinds of covering of animals adapted to their wants and restore all things to their former state. This is no situations on the globe. The covering of birds, in par- common contrivance: and now for the mechanism by ticular, cannot,' says Paley, escape the most vulgar which it is effected. The threads or lamine aboveobservation. Its lightness, its smoothness, its warmth mentioned are interlaced with one another, and the --the disposition of the feathers all inclined backward, interlacing is performed by means of a vast number of the down about their stem, the overlapping of their tips, fibres, or teeth, which the lamina shoot forth on each their different configuration in different parts, not to side, and which hook and grapple together. A friend mention the variety of their colours, constitute a vest- of mine counted fifty of these fibres in one-twentieth ment for the body so beautiful, and so appropriate to of an inch. These fibres are crooked, but curved after the life which the animal is to lead, as that, I think, we a different manner; for those which proceed from the should have had no conception of anything equally thread on the side towards the extremity of the feather perfect if we had never seen it, or can now imagine are longer, more flexible, and bent downwards; whereas anything more so. Let us suppose (what is possible those which proceed from the side towards the beginonly in supposition) a person who had never seen a bird ning or quill end of the feather, are shorter, firmer, and to be presented with a plucked pheasant, and bid to set turn upwards. The process, then, which takes place is his wits to work how to contrive for it a covering which as follows:-When two lamina are pressed together, shall unite the qualities of warmth, levity, and least so that these long fibres are forced far enough over the resistance to the air, and the highest degree of each: short ones, their crooked parts fall into the cavity made giving it also as much of beauty and ornament as he by the crooked parts of the others, just as the latch that could afford. He is the person to behold the work of is fastened to a door enters into the cavity of the catch the Deity, in this part of His creation, with the senti- fixed to the door-post, and there hooking itself, fastens ments which are due to it. the door; for it is properly in this manner that one thread of a feather is fastened to the other. The commendation which the general aspect of the feathered world seldom fails of exciting, will be increased by further examination. It is one of those This admirable structure of the feather, which, it is easy to see with the microscope, succeeds perfectly for the use to which nature has designed it; which use was, | nent. We have already seen that as the materials on not only that the lamina might be united, but that, when one thread or lamina has been separated from another by some external violence, it might be reclasped with sufficient facility and expedition. In the ostrich, this apparatus of crotchets and fibres, of hooks and teeth, is wanting; and we see the consequence of the want. The filaments hang loose and separate from one another, forming only a kind of down; which constitution of the feathers, however it may fit them for the flowing honours of a lady's head-dress, may be reckoned an imperfection in the bird, inasmuch as wings composed of these feathers, although they may greatly assist it in running, do not serve for flight. which the function of digestion is to be performed are numerous and diversified, so a difference exists in the parts which are subservient to it. Without altering the general plan of the function, or the essential parts of the organs concerned in it, nature makes such additional provisions, in the instincts by which the reception of food is guided, and in the organs by which it is assimilated, as are suited to the circumstances in which the animal is placed, to the food on which it is to subsist, and to the ulterior purposes which it is to serve in the world. Such evidences of design are very remarkable in the mammalia; and in few organs are they more powerfully instanced than in the teeth, between which But under the present division of our subject, our in form, structure, and position, and the kind of food business with feathers is, as they are the covering of on which each animal of this class is intended to subthe bird. And herein a singular circumstance occurs. sist, the most intimate connections present themselves. In the small order of birds which winter with us, from These relations-which, indeed, may be also traced in a snipe downwards, let the external colour of the fea- the shape of the jaw, in the mode of its articulation with thers be what it will, their Creator has universally the head, in the proportional size and distribution of given them a bed of black down next their bodies. the muscles which move the jaw, in the form of the Black, we know, is the warmest colour: and the pur-head itself, in the length of the neck and its position on pose here is, to keep in the heat arising from the heart and circulation of the blood. It is further likewise remarkable, that this is not found in larger birds; for which there is also a reason:-Small birds are much more exposed to the cold than large ones; forasmuch as they present, in proportion to their bulk, a much larger surface to the air. If a turkey were divided into a number of wrens (supposing the shape of the turkey and the wren to be similar), the surface of all the wrens would exceed the surface of the turkey, in the proportion of the length and breadth (or of any homologous line) of a turkey to that of a wren; which would be perhaps a proportion of ten to one. It was necessary, therefore, that small birds should be more warmly clad than large ones; and this seems to be the expedient by which that exigency is provided for. The oil with which birds prune their feathers, and the organ which supplies it, is a specific provision for the winged creation. On each side of the rump of birds is observed a small nipple, yielding upon pressure a butter-like substance, which the bird extracts by pinching the pap with its bill. With this oil or ointment thus procured, the bird dresses its coat, and repeats the action as often as its own sensations teach it that it is in any part wanted, or as the excretion may be sufficient for the expense. The gland, the pap, the nature and quality of the excreted substance, the manner of obtaining it from its lodgment in the body, the application of it when obtained, form, collectively, an evidence of intention which it is not easy to withstand. Nothing similar to it is found in unfeathered animals. What blind conatus of nature should produce it in birds? should not produce it in beasts?' As we have entered so fully into this subject when treating of other classes of beings, we shall not here revert to it, or bring forward illustrations of the truth of our proposition; the facts already detailed seem sufficient to display the wisdom which the great Creator has evinced in this department of the animal world. Nothing can be more worthy of remark than the exhaustless contrivances by which every difficulty is obviated, and nature moulded to the will of its Almighty Author. How many obstacles were to be overcome before a heavy body like that of an eagle or the mighty condor could be rendered buoyant in the air, and made to track its adventurous course so high above the earth as to be almost lost to human gaze! How many conditions were necessary to give safety and enjoyment to the smallest of the winged tribes, even after the first obstacles were overcome! And yet how wonderfully simple and efficacious the mechanism by which the whole has been accomplished! Structure of the Mammalia. We now arrive at the consideration of the mammalia, or those animals which suckle their young; and at the head of this great class we find man proudly pre-emi the trunk, and, in fact, in the whole conformation of the skeleton-have been noticed from very early ages, and frequently described. The purposes answered by the teeth are principally those of seizing and detaining whatever is introduced into the mouth, of cutting it asunder, and dividing it into smaller pieces, of loosening its fibrous structure, and of breaking down and grinding its harder portions. Four principal forms have been given to teeth, which accordingly may be distinguished into the conical, the sharp-edged, the flat, and the tuberculated teeth; though we occasionally find a few intermediate modifications of these forms. It is easy to infer the particular functions of each class of teeth, from the obvious mechanical actions to which, by their form, they are especially adapted. The conical teeth, which are generally also sharp-pointed, are principally employed in seizing, piercing, and holding objects; such are the offices they perform in the crocodile and similar reptiles, where all the teeth are of this structure; and such also are their uses in most of the cetacea or whale tribe, where similar forms and arrangements of teeth are found to prevail. The animals subsist on fish, and their teeth are therefore constructed very much on the model of those of fish; while those cetacea, on the other hand, which are herbivorous, as the manatus and dugong, have teeth very differently formed. The sharp-edged teeth perform the office of cutting and dividing the yielding textures presented to them: they act individually as wedges or chisels; but when co-operating with similar teeth on the opposite jaw, they have the power of cutting like shears or scissors. The flat teeth, of which the surfaces are generally rough, are used, in conjunction with those meeting them in the opposite jaw, for grinding down the food by a lateral motion, in a manner analogous to the operation of millstones in a mill. The tuberculated teeth, of which the surfaces present a number of rounded eminences, corresponding to depressions in the teeth opposed to them in the other jaw, act more by their direct pressure in breaking down hard substances, and pounding them as they would be in a mortar. The apparatus for giving motion to the jaws is likewise varied according to the particular movements required to act upon the food in the different tribes. The articulation of the lower jaw to the skull is somewhat similar to a hinge; but considerable latitude is given to its motions by the interposition of a movable cartilage between the two surfaces of articulation, a contrivance admirably answering the intended purpose. Hence, in addition to the principal movements of opening and shutting, which are made in a vertical direction, the lower jaw has also some degree of mobility in a horizontal or lateral direction, and is likewise capable of being moved backwards or forwards to a certain extent. In the conformation of the teeth and jaws, a remarkable contrast is presented between carnivorous and herbi vorous animals. In the former, of which the tiger may | ing, and to take in at once a prodigious quantity of be taken as an example, the whole apparatus for mastication is calculated for the destruction of life, and for tearing and dividing the fleshy fibres. The teeth are armed with pointed eminences, which correspond in the opposite jaws, so as exactly to lock into one another, like wheelwork, when the mouth is closed, and the muscles which close it are of enormous size and strength. In the herbivorous animals, on the contrary, as in the antelope, the greatest force is bestowed, not so much on the motions of opening and shutting, as on those which are necessary for grinding, and which act in a lateral direction. The surfaces of the teeth are flattened, and of great extent; and they are at the same time kept rough, like those of millstones, their office being in fact very similar to that performed by these implements of grinding. The Rodentia, or gnawing quadrupeds, are formed for subsisting on dry and tough materials, such as the bark and roots, and even the woody fibres of trees, and the harder animal textures; and their teeth are expressly adapted for gnawing, nibbling, and wearing away, by continued attrition, the harder texture of organised bodies. They are all furnished with two front teeth, generally very long, and having the exact shape of a chisel; while the molar or back teeth have surfaces irregularly marked with raised zig-zag lines, rendering them very perfect instruments of trituration. The beaver and common rat are examples among omnivorous rodentia, and the hare and rabbit among those that are principally herbivorous. The Quadrumana, or monkey tribes, approach nearer to the human structure in the conformation of their teeth, which are adapted to a mixed kind of food; while the other orders of mammalia exhibit gradations in the structure of their teeth corresponding to the varieties in the nature of their food. On comparing the structure of the digestive organs of man,' continues Dr Roget, with those of other animals belonging to the class mammalia, we find them holding a place in the series intermediate between those of the purely carnivorous and exclusively herbivorous tribes, and in some measure uniting the characters of both. The powers of the human stomach do not indeed extend to the digestion of either the tough woody fibres of vegetables on the one hand, or the compact texture of bones on the other; but still they are competent to extract nourishment from a wider range of alimentary substances than the digestive organs of almost any other animal. This adaptation to a greater variety of food may also be inferred from the form and disposition of the teeth, which combine those of different kinds more completely than in most mammalia. In addition to these peculiarities, we may also here observe, that the sense of taste in the human species appears to be affected by a greater variety of objects than in the other races of animals. All these are concurring indications that nature, in thus rendering man omnivorous, intended to qualify him for maintaining life wherever he could procure the materials of subsistence, whatever might be their nature, whether animal or vegetable, or a mixture of both, and in whatever soil or climate they may be produced; and for endowing him with the power of spreading his race, and extending his dominion over every accessible region of the globe. Thus, then, from the consideration of the peculiar structure of the organs of his frame, may be derived proofs of their being constructed with reference to faculties of a higher and more extensive range than those of any, even the most favoured, species of the brute creation.' There is one circumstance connected with the function of digestion, as displayed in certain of the mammalia, to which, as evidencing great and wonderful design and accommodation in structure to circumstance, we would particularly allude: it is the facility and power of the camel of abstaining long from drinking-a power which he is often necessitated to bring into effect during the long period of nine, ten, or even twelve days. It is by the singular structure of the camel's stomach that it is enabled to pass such a time without drink water, which remains in reservoirs pure and limpid, because these wells are so contrived that neither the fluids of the body nor of digestion can mix with it. What design is here!--and how redolent of wisdom, and how full of mercy! But let us endeavour to explain the nature of this structure which so evidently adapts the camel to be the inhabitant of the sterile and arid regions of the East:-Ruminating quadrupeds, or those which chew the cud, have two, three, or four stomachs, distinguished, when there are four, by the names of paunch, bonnet, many-plies, and caille. When the food is swallowed for the first time, it passes directly from the gullet into the paunch, where it undergoes some necessary changes, and it is then transmitted to the bonnet, to be mixed with the fluids of the cavity. This process is going on during the time the animal is grazing, when, from the incessant occupation of nipping off the grass, for which its teeth are so admirably suited, it has not leisure to chew it sufficiently. When afterwards reposing itself, however, the half-chewed aliment is brought again in successive little balls, from the bonnet into the mouth, where it is subjected to a perfect mastication; and when again swallowed, it passes directly to the many-plies, thence, after some time, to the caille, and ultimately to the intestines. In the camel, however, the paunch has two deep cellular appendages; and the bonnet, or second stomach, has its internal membrane hollowed into numerous deep cells, serving as reservoirs of water, to be used only as occasion requires; while the third stomach is alone appropriated to the immediate necessities of the body. Between the end of the gullet, then, and the orifice of this third stomach, extends, through the two first, a long muscle capable of drawing up the third stomach, so as to receive alimentary matters directly from the gullet, when the immediate wants of the animal are to be supplied; but when the fluid taken is meant to be used only in its long journeys through the deserts, this muscle is relaxed, and it is thus received into the two first stomachs, and transmitted onwards by these only at the necessary intervals. The Arabs who traverse these extensive plains, accompanied by these useful animals, are, it is said, sometimes obliged, when faint, and in danger of perishing from thirst, to kill one of their camels, for the sake of the water contained in these reservoirs, which is always found pure and wholesome. Compensation of Parts in Animated Nature. The evidences of design in creation are beautifully developed in what is called the compensatory structure of animals. By this is signified the supplying the defects of one organ by the structure of another part or organ. Paley has summed up a few striking instances of this nature. The short unbending neck of the elephant,' says he, is compensated by the length and flexibility of his proboscis. He could not have reached the ground without it; or, if it be supposed that he might have fed upon the fruit, leaves, or branches of trees, how was he to drink? Should it be asked, Why is the elephant's neck so short? it may be answered, that the weight of a head so heavy could not have been supported at the end of a longer lever. To a form, therefore, in some respects necessary, but in some respects also inadequate to the occasions of the animal, a supplement is added, which exactly makes up the deficiency under which he laboured. If it be suggested that this proboscis may have been produced, in a long course of generations, by the constant endeavour of the elephant to thrust out his nose (which is the general hypothesis by which it has lately been attempted to account for the forms of animated nature), I would ask, How was the animal to subsist in the meantime, during the process, until this prolongation of snout were completed? What was to become of the individual whilst the species was perfecting? Our business at present is simply to point out the relation which this organ bears to the peculiar figure of the animal to which it belongs. And herein all things correspond. The necessity of the elephant's proboscis | arises from the shortness of his neck; the shortness of the neck is rendered necessary by the weight of the head. Were we to enter into an examination of the structure and anatomy of the proboscis itself, we should see in it one of the most curious of all examples of animal mechanism. The disposition of the ringlets and fibres, for the purpose, first, of forming a long cartila-covery. Adams tells us that 1400 of these reticulations ginous pipe; secondly, of contracting and lengthening that pipe; thirdly, of turning it in every direction at the will of the animal; with the superaddition, at the end, of a fleshy production of about the length and thickness of a finger, and performing the office of a finger, so as to pick up a straw from the ground-these properties of the same organ taken together, exhibit a specimen not only of design (which is attested by the advantage), but of consummate art, and, as I may say, of elaborate preparation, in accomplishing that design. The hook in the wing of a bat is strictly a mechanical, and also a compensating, contrivance. At the angle of its wing there is a bent claw, exactly in the form of a hook, by which the bat attaches itself to the sides of rocks, caves, and buildings, laying hold of crevices, join-larities in the shape of the animal. The neck of the ings, chinks, and roughnesses. It hooks itself by this claw; remains suspended by this hold; takes its flight from this position: which operations compensate for the decrepitude of its legs and feet. Without her hook, the bat would be the most helpless of all animals. She can neither run upon her feet, nor raise herself from the ground. These inabilities are made up to her by the contrivance in her wing; and in placing a claw on that part, the Creator has deviated from the analogy usually observed in winged animals. A singular defect required a singular substitute. The crane kind are to live and seek their food amongst the waters, yet, having no web feet, are incapable of swimming. To make up for this deficiency, they are furnished with long legs for wading, or long bills for groping; or usually with both. This is compensation. But I think the true reflection upon the present instance is, how every part of nature is tenanted by appropriate inhabitants. Not only is the surface of deep waters peopled by numerous tribes of birds that swim, but marshes and shallow pools are furnished with hardly less numerous tribes of birds that wade. suspect. The eye is a multiplying glass, with a lens If, But the works of the Deity are known by expedients. Where we should look for absolute destitution, where we can reckon up nothing but wants, some contrivance The common parrot has, in the structure of its beak, always comes in to supply the privation. A snail, withboth an inconveniency and a compensation for it. out wings, feet, or thread, climbs up the stalks of plants When I speak of an inconveniency, I have a view to by the sole aid of a viscid humour discharged from her a dilemma which frequently occurs in the works of skin. She adheres to the stems, leaves, and fruits of nature-namely, that the peculiarity of structure by plants by means of a sticking plaster. A mussel, which which an organ is made to answer one purpose, neces- might seem by its helplessness to lie at the mercy of sarily unfits it for some other purpose. This is the case every wave that went over it, has the singular power before us. The upper bill of the parrot is so much of spinning strong tendinous threads, by which she hooked, and so much overlaps the lower, that if, as in moors her shell to rocks and timbers. A cockle, on the other birds, the lower chap alone had motion, the bird contrary, by means of its stiff tongue, works for itself could scarcely gape wide enough to receive its food; a shelter in the sand. The provisions of nature extend yet this hook and overlapping of the bill could not be to cases the most desperate. A lobster has in its conspared, for it forms the very instrument by which the stitution a difficulty so great, that one could hardly conbird climbs, to say nothing of the use which it makes jecture beforehand how nature could dispose of it. In of it in breaking nuts and the hard substances upon most animals, the skin grows with their growth. which it feeds. How, therefore, has nature provided instead of a soft skin, there be a shell, still it admits of for the opening of this occluded mouth? By making a gradual enlargement. If the shell, as in the tortoise, the upper chap movable, as well as the lower. In consists of several pieces, the accession of substance is most birds the upper chap is connected, and makes made at the sutures. Bivalve shells grow bigger by but one piece, with the skull; but in the parrot, the receiving an accretion at their edge; it is the same with upper chap is joined to the bone of the head by a strong spiral shells at their mouth. The simplicity of their ligament or membrane placed on each side of it, which form admits of this. But the lobster's shell being aplifts and depresses it at pleasure. plied to the limbs of the body, as well as to the body itself, allows not of either of the modes of growth which are observed to take place in other shells. Its hardness resists expansion, and its complexity renders it incapable of increasing its size by addition of substance to its edge. How, then, was the growth of the lobster to be provided for? Was room to be made for it in the old shell, or was it to be successively fitted with new ones ? If a change of shell became necessary, how was the lobster to extricate himself from his present confinement ?-how was he to uncase his buckler, or draw his legs out of his boots? The process which fishermen The spider's web is a compensating contrivance. The spider lives upon flies, without wings to pursue them; a case, one would have thought, of great difficulty, yet provided for, and provided for by a resource which no stratagem, no effort of the animal, could have produced, had not both its external and internal structure been specifically adapted to the operation. In many species of insects the eye is fixed, and consequently without the power of turning the pupil to the object. This great defect is, however, perfectly compensated, and by a mechanism which we should not case? Because it yields a pleasure to the sight, both of men and other living creatures; for the Creator has not denied the feeling of delight to the meanest reptile which crawls. All is beautiful, it would appear, in the estimation of one or other of living creatures. The most insignificant little flower, now blooming far from the haunts of men, in some remote wilderness, does not, as has been said, waste its sweetness on the desert air. It furnishes an object of pleasing gratification to some description of sentient creatures, perhaps so small as to be imperceptible to our naked eye. have observed to take place is as follows:-At certain | comparable for their beauty. And why is all this the seasons the shell of the lobster grows soft; the animal swells its body; the seams open, and the claws burst at the joints. When the shell has thus become loose upon the body, the animal makes a second effort, and by a tremulous spasmodic motion, casts it off. In this state the liberated but defenceless fish retires into holes in the rock. The released body now suddenly pushes its growth. In about eight-and-forty hours, a fresh concretion of humour upon the surface-that is, a new shell-is formed, adapted in every part to the increased dimensions of the animal. This wonderful mutation is repeated every year.' In the changing of the colour of the chameleon, we see one of the beautiful compensatory provisions of nature. This little animal, which is common in the East Indies and some other Asiatic countries, lives upon flies, beetles, or other insects, which it catches by climbing up shrubs or trees, and darting out its tongue; but its pace is slow, and as insects have good eyes to perceive the approach of an enemy, they would be sure to make their escape in the present case, unless the chameleon approached them in disguise. This, therefore, it invariably does. As it passes among green leaves, it is of a green colour; and when it glides by any of a red or yellow tinge, so does it change its hue to red or yellow. So closely does it assume not only the shades and colours, but even the shapes of the leaves around, that a spectator might look among the foliage for some minutes before discovering it. By carrying our observation upward from the mere physical organisation of man, to the mind which he possesses, and is able to exert in reference to both sensible objects and abstract subjects, we have still greater reason to admire the proofs of design and goodness in an overruling Creator; for we all feel that this principle of mind-how constituted we do not here stop to inquire-is in harmony with the other works of creation around us. For example, how much are our minds suited to the recognition of what is beautiful and harmonious in nature and art. This, however, admits of a few separate observations: Beauty. The wisdom of the great original Contriver is eminently manifested in that property of inanimate and animate objects which we call beauty. Here there is an evident fitness between the taste and habits of animals, human beings included, and what can be seen by the eye. We feel pleasure in contemplating the works of nature most obvious to our senses; and we cannot but remark, that that which is loathsome is not ordinarily presented to the eye. The splendid colouring of the vegetable kingdom, the smooth or spotted skins of the brute creation, and the lovely plumage of the feathered tribe, all give us delight in the contemplation. Consider, also, how beautiful is the outward appearance of the human form. Reflect on what the parts and materials are of which the fairest body is composed, and no further observation will be necessary to show how well these things are wrapped up, so as to form a mass which will be capable of symmetry in its proportion, and of beauty in its aspect; how the bones are covered the bowels concealed-the roughness of the muscle smoothed and softened; how over the whole is drawn an integument, the skin, which converts the disgusting materials of a dissecting-room into an object of attraction to the sight, or one upon which it rests at least with ease and satisfaction. The more minutely that we inspect the works of nature, the greater cause have we to wonder at the extraordinary perfection and beauty everywhere prevalent. The microscope develops splendours in the creation of insects which we can hardly comprehend. The back of a diamond-beetle exhibits an assemblage of brilliant colours and glittering gems more splendid than any artificial arrangement of the most precious stones. The colours of the feathers of birds in tropical climates, and the skins of the fishes of Ceylon, are in Placing agreeableness of aspect entirely out of the question, there is another purpose answered by the skin-and that is concealment. Were it possible to view through this integument the mechanism of our bodies, the sight would frighten as much as it would disgust us. Ďurst we make a single movement, or stir a step from the place we were in, if we saw our blood circulating, the tendons pulling, the lungs blowing, the humours filtrating, and all the incomprehensible assemblage of fibres, tubes, pumps, valves, currents, pivots, which sustain an existence at once so frail and so presumptuous ? In clothing the human frame with a covering of skin, the Creator has not omitted to vary its character according to local necessities. The skin is most beautiful on the face, because the face is most exposed to observation; it is softest where least liable to injury, and hardest or firmest in texture where it is most subject to be pressed upon. There is not less sign of contrivance in the manner in which it ceases at the extremities of the toes and fingers. A man has only to look at his hand, to observe with what nicety and precision that covering, which extends over every other part, is here superseded by a different substance and a different texture. Why do we find the skin cease at our fingers' ends, or on the back part of the fingers, and not the fore part? Because something hard or horny was required on these parts, by which we could hold fast or lift nimbly objects which we wished to grasp or seize upon. Nails, therefore, supersede the skin on such places. The same forethought is visible in the covering of our heads. What could have been a more beautiful or appropriate substance wherewith to cover the head and preserve the hard bony skull from injury, than the hair, a substance at once light, warm, and graceful? DESIGN IN VEGETABLE PHYSIOLOGY. In accordance with our intentions in glancing through most of the natural sciences, and bringing home to the main object of our labours treasures illustrative of design from them all, let us now turn our attention to those afforded by the vegetable kingdom of nature. And first, of the mutual relations that exist between animals and vegetables; in considering which, we shall find that these two great organised kingdoms of the creation are made to co-operate in the execution of the same design; each ministering to the other, and preserving that due balance in the constitution of the atmosphere which adapts it to the welfare and activity of every order of beings, and which would soon be destroyed were the operations of any one of them to be suspended. It is impossible to contemplate so special an adjustment of opposite effects without admiring this beautiful dispensation of Providence, extending over so vast a scale of being, and demonstrating the unity of plan on which the whole system of organised creation has been devised.' We said in a former part of this essay that two principles of atmospheric air were oxygen and carbon; that the former was as essential to animal life as the latter was obnoxious to it; but that, on the other hand, carbon was indispensable to the continuance of vegetable organisations. We will now endeavour to explain this by a short account of the phenomena of respiration, as displayed in the two kingdoms. Among animals, the function of respiration is that by which the blood, received into its vessels from the alimentary canal, is, during its subsequent circulation, |