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amples of elegant minuteness in the kingdom of nature ? Many of the latter entirely elude our organs of sight; yet these, when scrutinized by the help of a microscope, present the most perfect symmetry of parts, under almost every possible form. We behold with astonishment an adaptation of these parts, in common with those of the largest animals, to the purposes of life,—limbs or other means of locomotive power, eyes and other organs of sense suited to the element in which they reside, a heart, a stomach, an intestinal canal, an apparatus for securing the requisite supplies of food, an apparatus often singularly constructed, and not easily explained; in some, for example, a wheel, which by rapid gyrations produces a vortex sufficient to attract to the mouth the particles swimming about, yet by some wonderful contrivance prevents the waters of the eddy from descending into the gullet with the particles gorged. In some of the larger insects whose bodies are transparent, the wonders of interior organization are laid open to the inspection of every individual, and the naked eye may perceive the vital fluid projected through one channel from the tail to the thorax by the constant playing of the heart, and descending again in crystal globules through the trunk to the tail, where it seems the vital functions are performed. How beautiful and highly finished the exterior decorations of others,—the feathery down with which they are covered, or the glossy and radiant hues with which their bodies are gilded or japanned,—their net-work of eyes,—the fabric of their wings and antennæ ! Let the most delicate and powerful instruments be employed, no flaw can be detected in these or in any of the works of nature,—nothing rude or inelegant. The utmost efforts of human power have not been able to give such polish or perfection to the works of art.- Besides magnitude and minuteness, variety itself may be justly regarded as an indication of power. And to what an extent is this displayed in the system of nature ! To speak only of animated beings, what variety of form as well as of kind do we perceive among them ? and of form in the individuals of the same species, so similar, yet so truly discriminated by some peculiarity of size, of colour, of feature, of expression, or of temper. Withdraw the models of nature, and what sculptor or painter would be able to exhibit, in his works, such an endless diversity as appears in the countenance alone.*
“ Though every thing must be alike easy to an infinite and almighty Being, yet according to human apprehension, it appears extremely wonderful that we tind almost without exception in those specks of life, (insects and animals
The principal effects of W18Dom are, admirable arrangement, with all requisite provisions for ensuring the perpetuity of the work,-much accomplished at little expense,-and in the best form, showing that the proper means were selected and fitly applied. Facts in the system of Nature, corresponding to these, and all other results of wisdom, everywhere obtrude themselves on the most careless observer. We found it impossible to trace the bare proof of design and contrivance, without being struck with indications of admirable arrangement ; and the very detail of provisions against the perturbation or destruction of the order of nature, which belonged to that proof, and could not be given without evincing their propriety and sufficiency, has anticipated all that is requisite for the demonstration of wisdom in this department. To show that much is accomplished at the least expense, in the shortest way, and with the happiest effect, we shall not enter into a long induction of particulars. Let the appeal be to the few following facts. 1. The manifold use to which the single law of gravitation is applied. Suppose gravity essential to matter, though the existence and operation of the law could not in that case be avoided, how admirably has the planetary system been adjusted to both for preserving the respective distances of the globes, maintaining their annual revolutions, producing the vicissitude of seasons, attaching secondaries to their primaries, effecting the libration of the secondaries, correcting inequalities, and ever harmonizing the whole. 2dly, The atmosphere is at once by its composition the cherisher of life, by its elevation the medium of light, by its density the organ of solar heat, and both in these and other respects adapted to a great variety of other purposes in the economy of nature. This is an example of a different description from the former. Here we discern nothing like original necessity requiring correspondent adaptations. The composition, elevation, and density of the atmosphere were all contingent; but the mass as it is, exhibits the result to be expected from an all-comprehensive wisdom, which accomplishes much with the utmost ease, and in the best manner, by the simplestômeans. None of the gases of which atmospheric air culæ), whose minuteness renders them almost imperceptible to the eye of man, a greater number of members to be put in motion, an apparatus more complex and curious, a plan seemingly of deeper contrivance ; in short, more elegance and workmanship (if the term may be excused) in the composition, more beauty and ornament in the finisbing, than are seen in the enormous bulk of the elephant, the crocodile, and the whale." These last are indicative of power in another form.” BAKER's Employment for the Microscope, Part ii. Introduction.
is composed, is by itself fitted for the purposes of life; yet by their combination in certain proportions, the fluid is attempered to the vital constitution, not only of man, but of every animated being. It furnishes on each inspiration the proper quantity of oxygen, neither more nor less, which the volume drawn into the lungs of the land-animals, or passing the gills of fishes, or surrounding the spiracula of insects, ought to furnish according to the constitution of these several classes of beings, who are all equally dependent on its presence. Vegetables too, of every deseription, imbibe its cherishing influence. Their leaves are found to answer the purpose of lungs; while by some process not yet satisfactorily explained, they also give out the vital gas in vast abundance to repair the loss oecasioned by the respiration of animated beings, that thus in the very region (next the earth) where the atmosphere is most apt to be impoverished, it may be regenerated, and its salubrity maintained;—a provision resembling that of the saline quality of the ocean, so requisite to prevent the otherwise unavoidable putridity of the waters.
We formerly noticed the uniformity of the mode of generation ; and can we forbear to remark here the uniformity that appears in the manner of sustaining both animal life and the vegetative vis in all their respective subjects,-particularly the common necessity of air, and the manifest relation which all the different organs formerly mentioned, have to the extraction of its vital principle ? But the simplicity of the means by which many effects are produced, as an indication of wisdom, is our present theme. And not to dwell on the adaptation of air for the nourishment of fire, the occasional production of water, and various other purposes, let us remark how much its contexture and elevation contribute to the phenomena of light. Transparent and viewless, it readily transmits to us the rays of the sun, while it unites them at the same time so as to magnify the quantity of heat. But this is not all, “ it both causes and continues the day, which though it be a necessary consequence of the sun's irradiation upon the atmosphere, is rather the work of the latter, than the production of the sun himself.” Suppress the atmosphere, and then the refracting medium being lost, the rising of that luminary would not be preceded, nor his setting followed, by twilight. His effulgence would burst on the pained eyeball at once, and the moment he sank beneath the horizon it would be as suddenly extinguished. No aurora would announce his approach, no evening would prolong the advantages of day and gently usher in the night. The
very distinction indeed between day and night would scarcely exist; for even while traversing his path in the heavens, the source of day would be shorn of his diffusive splendour, and exhibit the appearance only of a flaming orb upon a mournful canopy,-a black abyss of darkness, undispelled, where the stars would be equally visible with himself. His rays would only shed a dismal glare on a few objects around the spectator, like a distant fire blazing on the darkness of the night. It is the atmosphere that lifts the azure arch over our head; and conjoins the many-coloured pencils of light into that uniform splendour, that white illumination, so grateful to the organs of vision, and so wonderfully adapted for displaying the beauties of colour in other objects, and indeed for unveiling expansively all the beauties of nature. This it is that gradually loses itself to the eye in the cerulean blue of the heavens.
Between our atmosphere and the atmospheres of other planets, a great difference has been discovered both in density and height; but we know from experience, that the ratio of both in our atmosphere is fitly accommodated to our distance from the sun. The variations in weight of which it is susceptible, and its great elasticity, not only render it capable of being applied to many useful purposes of art, but wondrously multiply its utilities in the general economy of nature. summary view, the air which promotes vegetation, which reinvigorates the vital fluid, which provides for us the incalculable benefits dependant on ignition, and to which we are indebted for the cheerful light of day, presents at the same time the fittest element for the motion of winged animals, is the proper region for the production and action of many useful meteors, and the best medium for the propagation of sound, the elevation and suspension of odours, the formation of vapours, of winds, of snow, of rain, and of dew. Without it, the peculiar structure of the feathered race, and of thousands of insects, the faculty of speech in man, the organs of voice and of song
in other animals, and the senses of hearing and smelling, had been all equally useless ; there had been “ no balancings of the clouds ;” no restoration of the arid or exhausted soil.
There is, further, a certain meliority in the whole constitution of things celestial and terrestrial, which no thinking being can fail to perceive. The general disposal of all is clearly the most advantageous for amalgamating properties, laws, and relations, otherwise discordant, into one
harmonious system, duly adjusted to ulterior objects. The harmony we have already considered ; and it is the last idea, the happy adaptation of the whole system to ulterior objects, we presently advert to. This evinces the meliority of much in the economy of nature, which may seem to be so necessarily the result of physical causes, that it could not be prevented, supposing them to exist. Cold, for example, must necessarily convert vapour into snow, and water into ice. But this is a happy effect in relation to man considered as an inhabitant of the temperate and especially of the polar regions, which are so long deprived of the genial influence and cheering rays of the sun. In warmer climates the brilliancy of snow and the bright reflections of icy plains and mountains, are not needed to compensate for deficiency of light; and the heat of the climate prevents the bad effects which heavy rains in winter would obviously have in colder regions. Snow rests on the cherished soil like a thick covering of the finest wool.* Say, on the other hand, that sea and land-breezes, monsoons, and tropical rains, must necessarily arise from the near presence of the sun, are they not at the same time happily fitted both for tempering the heat of his presence, and giving full play to its influence, and thus rendering that otherwise destructive power conducive to the purposes of life and of health, as the source of a most luxuriant vegetation ? The electric fluid when accumulated over the equator is combined with the atmosphere, which there rises to its greatest height, and thus serves by its the storms it produces, to purify the air. But if that fluid naturally tends to flow off at the poles, and to kindle into the aurora borealis and australis in the superior region, which it easily gains as the stratum of air is diminished by the rotation of the earth, this phenomenon is evidently preferable in climates long left to the darkness of winter. It is greatly useful as a source of light, often equal to that of the moon; and then, its expansive splendour, its singular yet pleasing motions, the magnificence of its forms, and the variety and brilliancy of its colours, compensate, in some measure, for the want of that
That snow, in such regions, is preferable to the tropical deluges of rain, Darwin remarks, Ist, Because as the winter is longer, snow dissolves gradually, and thus carries away less from the soil ; 2dly, Because it protects vegetables from the severity of the frost, since it is always in a state of thaw where it is in contact with the earth. The beat of the earth being about 48, and that of thawing snow 32, the vegetables are preserved in a temperature of about 40. Bot. Gar. vol. i. note xii. But for their covering of snow, the power of frost would rend the rocks and crumble down the mountains of the frigid zone.