Abbildungen der Seite
PDF
EPUB

of these globes—how many eyes of sentient beings might be affected by the diversities of colour, shape, and motion, which would thus be produced—and what a variety of shades of light and colour, and what a diversity of scenery, would be produced, according to the distances of the respective globes from the central luminary. After what we have just now stated, however, we may rest satisfied with joining in the pious exclamation of one who had just finished a devout survey of the structure of the human frame: "Marvellous are thy works, and that my soul knoweth right well. How precious are thy thoughts unto me, O God!" (or, as the words might be rendered,) *' How precious are thy wonderful contrivances concerning me, O God! how great is the sum of them! If I should count them, they are more in number than the sand." In what direction soever I turn mine eyes, whatever portion of thy works I investigate, "Jam still with tAee."* Thine infinity and unsearchable wisdom are impressed on every object, so that I feel myself every moment encompassed by thine immensity, and am irresistibly led to wonder and adore.

I shall now conclude these reflections on vision, with two or three additional remarks. It is worthy of notice, in the first place, that the eye has the power of adapting itself to objects placed at different distances. By means of some delicate pieces of mechanism, not hitherto satisfactorily explained, it can perceive, with distinctness, a large object, at the distance of six miles, and the next moment it can adjust itself to the distinct perception of an object at the distance of six inches; so that it acts the part both of a telescope and a microscope, and can be instantaneously adjusted to perform either as the one instrument or as the other. This necessarily supposes a corresponding alteration in the state of the organ, every time we lid our eye from a near, to look at a distant object. Either the cornea is somewhat flattened, or the crystalline humour is pushed backwards, or both these changes, in combination with others, may concur in causing the rays from distant objects to unite exactly on the retina, without which distinct vision cannot be produced. This contrivance, in whatever kind of mechanism it may consist, is one which art would vainly attempt to imitate. We can see objects that are near us, with a microscope, and those that aredistont, with a telescope ; but we would in vain attempt to see distant objects with the former, or those that are only a few inches from us with the latter, without a variety of changes being made in the apertures and positions of the glasses belonging to the respective instruments. In this respect, therefore, as well as in every other, the eye is an optical instrument, incomparably superior to any

• Psalm exxxlx. if, 17,18.

instrument or imitation that art tan produce. and, were it not for the peculiar property now described, it would be almost unfit for the purpose of vision, notwithstanding alt the other delicate contrivances which enter into its construction. If it were adjusted only for the distinct perception of distant objects, every object within the limits of an ur4sViar.y apartment would appear a mass of confusion; and were it adjusted solely for viewing objects within the limits of a few feet or inches, the glories of the heavens, and the beautiful landscape of the earth, would be veiled from our sight as ifthey were enveloped in a mist.

Another circumstance worthy of attention, is, the power which the pupil of the eye possesses of contracting or enlarging the aperture or hole through which the light is admitted. When the light is too weak, the pupil is enlarged; when it is too strong, it is again contracted. Accordingly, we find, that when we enter a darksome apartment, though, at first, nothing can be accurately distinguished, yet, in the course of a minute or two, when the pupil has had time to dilate, we can perceive most objects with considerable distinctness. And, on the other hand, when wo pass from a dark room to an apartment lighted up with a number of lustres, we feel uneasy at the sudden glare, till the pupil has contracted itself, and excluded a portion of the superfluous rays. Were it not for this property, we should for the most part either be surrounded with a disagreeable gloom or oppressed with an excessive splendour. It is for this reason, that we are unable to look upon the sun without being dazzled, and are under the necessity of closing the eyelids, or of turning away the head, when a strong light suddenly succeeds to darkness.

Again, it may not bo improper to observe, how wisely the Author of nature has fixed the distance at which we ordinarily see near objects most distinctly. This distance is generally from five to eight inches from the eye. But had the eye been formed for distinct vision at the distance of only one inch, the object would have obstructed the light, and room would have been wanting for the performance of many necessary operations, which require the hand to intervene between the eye and the object. And had the limits of distinct vision for near objects been beyond two or three feet, sufficient light would not have been afforded for the inspeciion of minute objects, and we could neither have written a letter, nor have read a book, with the same convenience and ease we are now enabled to do.

From the preceding descriptions and remarks, it will evidently appear, with what admirable skill the different parts of the organs of vision are constructed, and how nicely they are adapted to the several ends they were intended to subserve. Were any one of these parts wanting, or obstructed in its functions, vision would either be impeded, or rendered painful and distressing, or completely destroyed. If any of the humours of the eye were wanting—ifihey were less transparent—ifihey were of a different refractive power —or if they were of a greater or less convexity than they now are, however minute the alteration might be, vision would inevitably be obstiicted, and every object would appear confused and indistinct. If the retina, on whicfthc images of objects are painted, were fiat, instead of being concave, while objects in the middle of the view appeared distinct, every object towards the sides would appear dim and confused. Ifthe cornea were as opaque as the sclerotica, to which it is joined, or if the retina were not connected with the optic nerve, no visible object could possibly be perceived. If one of the six muscles of the eye were wanting, or impeded in its functions, we could not turn it to the right; if a second were deficient, we could not turn it to the left; if a third, we could not lift it upwards; if a fourth, we could not move it downwards; and if it were deprived of the other two muscles, it would be apt to roll about in frightful contortions. If the eyes were placed in any other part of the body than the head—if they were much more prominent than they now are—if they were not surrounded by the bony socket in which they are lodged—and if they were not frequently covered by the eyelid—they would be exposed to a thousand accidents from which they are now protected. If they wanted moisture, and if they were not frequently wiped by the eyelids, they would become less transparent, and more liable to be inflamed; and if they were not sheltered by the eyebrows, the sweat and moisture of the forehead would frequently annoy them. Were the tight which acts upon them devoid of colour—were it not reflected from objects in every direction— were its motion less swift, or its particles much larger than they now are—in short, were any one circumstance connected with the structure of this organ, and with the modification of the rays of light, materially different from its present arrangement, we should either be subjected to the hourly recurrence of a thousand painful sensations, or be altogether deprived of the entertainments of vision.

How admirable an organ, then, is the eye, and how nicely adapted to unveil to our view the glories of the universe! Without the application of any skill or laborious eflorts, on our part, it turns in every direction, transports us to every surrounding object, depicts the nicest shades and colours on its delicate membranes, and

■ Taxes In. at once, the landscape of the world, At a *mnU inlet, which a grain might clow. And half creates the wond'rous world we see."

Foimr.

—How strikingly does it display, in every part of its structure and adaptations, the marks of benevolent design, and of Infinite Intelligence! However common it is to open our eyes, and to

behold, in an instant, the beauties of an extensive landscape, and however little we may be accustomed to admire this wonderful eflect.—there is not a doctrine in Religion, nor a fact recorded in Revelation, more mysterious and incomprehensible. An excellent French writer has wet observed—" The sight of a tree and of the sun, which God shows me, is as real and as immediate a revelation as that which led Moses towards the burning bush. The only difference between both these actions of God on Moses and me, is, that the first is out of the common order and economy; whereas the other is occasioned by the sequel and connexion of those laws which God has established for the regulation both at man and nature."

If, then, the eye of man (who is a depraved inhabitant of a world lying partly in ruins) is an organ so admirably fitted for extending our prospects of the visible creation—we may reasonably conclude, that organized beings, of superior intelligence and moral purity, possess the sense of vision in a much greater degree of perfection than roan, in his present state of degradation— and that they may he enabled, by their natural organs, to penetrate into regions of the universe far beyond what man, by the aid of artificial helps, will ever be able to descry. It may not be altogether extravagant, nor even beyond the reality of existing facts, to suppose, that there are intelligences in the regions of Jupiter or Saturn, whose visual organs are in so perfect a state, that they can descry the mountains of our moon, and the continents, islands, and oceans which diversify our globe, and are able to delineate a map of its surface, to mark the period of its diurnal rotation, and even to distinguish its cities, rivers, and volcanoes. It is quite evident, that it must be equally easy to Divine 'Wisdom and Omnipotence, to form organs with powers of vision far surpassing what I have now supposed, as to form an organ in which the magnificent scene of heaven and earth is depicted, in a moment,within the compass of half an inch. There are animals whose range of vision is circumscribed within the limits of a few feet or inches ; and, had we never perceived objects through an organ in the same state of perfection as that with which we are furnished, we could have formed as little conception of the sublimity and extent of our present range of sight, as we can now do of those powers of vision, which would enable us to descry the inhabitants of distant worlds. The invention of the telescope shows, that the penetrating power of the eye may be indefinitely increased ; and since the art of man can extend the limits of natural vision, it is easy to conceive, that, in the hand of Omnipotence, a slight modification of the human eye might enable it, with the utmost dis. tinctness, to penetrate into regions to which the imagination can set no bounds. And, therefore,

It is not unreasonable to believe, that, in the uture world, this will be one property, among others, of the resurrection-body, that it will be furnished with organs of vision far superior to the present, in order to qualify its intelligent inhahitant for taking an ample surrey of the "riches and glory"' of Lhe empire of God.

I hare dwelt somewhat particularly on the functions of the eye, in order to show, that it is only when we take a minute inspection of the operations of the Creator, that his Infinite Wisdom and Intelligence are most distinctly perceived. The greater part of Christians will readily admit that the Wisdom of God is manifested in every object, but few of them take the trouble to inquire in what particular contrivances and adaptations this wisdom is displayed; and, therefore, rest satisfied with vague and general views, which seldom produce any deep impression on the mind. '' The works of theLord," which are "great" and admirable," must be sought out by all those who have pleasure thereinand the more minutely they are inspected, the more exquisite and admirable do all his arrangements appear.

Were we to enter into an investigation of the visual organs of the lower animals, and to consider the numerous varieties which occur in their structure, position, and movements, and how nicely the peculiar organization of the eye is adapted to the general structure of the animal, and to its various necessities and modes of existence—the operation of the same inscrutable Wisdom and Intelligence would meet our eye at every step. Birds, for example, which procure their food by their beak, have the power of seeing distinctly at a very small distance ;and, as their rapid motion through the air renders it necessary that they should descry objects at a considerable distance, they have two peculiar mechanical contrivances,connected with their organs of vision, for producing both these effects. One of these contrivances consists in a flexible rim formed of bone, which surrounds the broadest part of the eye, and by occasionally pressing upon its orb, shortens its focal distance, and thus enables it to inspect very near objects. The other consists of a peculiar muscle, which draws back, as occasion requires, the crystalline humour, by which means it can take a distinct view of a distant landscape; and can pass from the sight of a very near, to the sight of a distant object, with rapidity and ease. In fishes, which live in a medium of a different refractive power from that of air, the crystalline humour has a greater degree of convexity, and more nearly approaches to a globular form than that of land animals—which conformation is essentially requisite to distinctness of vision in the watery element. A fish of course cannot see distinctly in air, nor a quadruped under water ; and every person who has dived" Into the water with his eyes open, knows, that

though he may perceive the general forms and colours of objects, his vision is obscure and indistinct. In hares and rabhits the eyes are very convex and prominent, so that they can see nearly quite round them ; whereas,in dogs, which pursuo these animals, the visual organs are placed moto in the front of the head, to look rather before than behind them. Some animals, as cuts and owlswhich pursue their prey in the dark, have th<" pupil of their eye so formed as lo be capable of great expansion, so that a few rays of light may make a lively impression on their retina; while the eagle, which is able to look directly at the sun, has its pupil capable of being contracted almost to a point. Insects, such as the beetle, the fly, and the butterjly, whose eyes are incapable of motion, have several thousands of small transparent globes set in aconvex hemisphere, everyone of which is capable of forming an image of an object; so that they are enabled to view the objects around them without moving their heads, fiut, it would be beyond the limits of my plan to prosecute this subject any farther; enough has already been stated, to show, that the eyes of men and other animals are master-pieces of art, which far transcend the human understanding; and that they demonstrate the consummate wisdom of Him who planned and constructed the organical functions of the various tribes of animated existence.

I shall now conclude this branch of my subject, by presenting an instance or two of the mechan,sm of the bones, and the movements it is fitted to produce.

The bones of the human frame are articulated, or connected together, in different ways, but most frequently in the following manner. Either, 1. a bone with a round head is articulated with a cavity, and plays in it as a ball in a socket; or, 2. they are connected together by a hingelike articulation, which enables a bone to move up or down, backwards or forwards, like a door upon its hinges. An idea of these two motions, -and the purposes they serve, may be obtained, by considering the construction of the pedestal of a telescope, and the joints on which it moves. One of the joints is of ihe nature of a hinge, by which a vertical motion, or a motion upward* and downwards is produced. A horizontal motion, or a motion towards the right hand or the led, is produced by a pivot moving iu a socket; so that, by these two motions, the telescope can be mode to point in any direction. Such is the nature of the articulations of the bones, and the movements they produce ; and wherever one or other of these motions, or both of them combined, are requisite for the comfort and convenience of the individual, such a power of motion is uniformly found to exist. If the movement of a joint in every direction would, in any particular case, be found inconvenient, the hinge-like articulation is fixed upon ; but if a motion in ever- direction \e required for the convenient use of particular members, and for the variety of evolutions which a sentient being may have occasion to make, the ball and socket articulation is comhined with the former.

For example, let any person, for a moment, consider the joints of his fingers, and compare them with the joint at his wrist, where the hand is connected with the fore arm. If he hold the back of his hand upwards, he will find that he can move his fingers upwards, or downwards; out he cannot turn them to the right hand, or to the left, so as to make them describe a circular motion. He will also find that his wrist is capable of a similar movement, so that the hand may be bent in a vertical direction. But, in addition to this motion, it is also capable of being turned in a horizontal direction, or from one side to another. In the former case, we have an example of the hinge articulation; in the latter, it is comhined with an articulation which produces nearly the same effect as a pivot moving in a socket. Now, had the joints of the 6ngers been capable of the same motions as the wrist, the hand would have lost its firmness, and been incapable of performing a variety of mechanical operations which require objects to be held with a steady grasp. On the other hand, if the joint of the wrist had been formed in the same manner as the joints of the fingers, and confined to a vertical motion, the hand would have been incapable of one out of a hundred varied movements, which it can now perform with the greatest ease. In this case, we could not have bored a hole with a gimblet, cut down corn with a sickle, digged the earth with a spade, sewed clothes with a needle, tossed up a ball, or turned up the palm of the hand, for any of the useful purposes for which that motion was ordained. In short, without the rotatory motion of tho wrist, the greater part of the operations connected with gardening, agriculture, cookery, washing, spinning, weaving, painting, carving, engraving, building, and other mechanical arts, could not be performed; and such of them as could be effected t would be accomplished only with the greatest inconvenience and labour. Any person may convince himself of this, by holding his hand in a horizontal position, and preventing his wrist joint from turning round, and then by trying what operations he can easily perform without the rotatory motion; and he will soon perceive with what exquisite skill the numerous movements of our animal frames have been contrived by the great Author of our existence. In each hand there are 27 bones, all of which are essential to the different motions we wish to perform. Every Soger is composed of three bones, connected together by articulations, muscles, and ligaments. If, instead of three, each finger were composed ofonly one bone, it would be quite impossible for us to grasp a single object.

The same admirable contrivance may K, per ceived in the movements of which the head is susceptible. It was requisite, in order to out convenience and comfort, that we should be ensbled tu move our head backwards or forwards— to look up towards the heavens, or downwards to the ground. It was also expedient, that it should have a power of turning to the right, or to the left, so as to take in a considerable portion of a circle, without being under the necessity of turning round the w"holc body. Accordingly we find, that both these motions are provided for, in the manner in which the head is connected with the vertebra. The head rests upon the uppermost of these bones, to which it is connected by a hinge joint, similar to those in the fingers, which allows it to move backwards and forwards; and, by means of a round, longish process, or projection, which moves in a socket, it is enabled to move horizontally, as upon an axis. Had the first motion • been wanting, we could not have looked up to the zenith, without laying flat on our back ; nor could we have looked to the ground, without placing our bodies in a prone position, and, in such a case, we could never have seen our own feet, unless when they were bent considerably forward. Had the second motion been wanting, we could have looked to nothing except the objects directly before us, without the trouble of turning round the whole body, either to the right, or to the left. But in the construction of our corporeal system, every thing is so arranged and adapted to another, as at once to contribute to ease, and facility of motion, in all the varied operations and movements we have occasion to perform; which circumstance forcibly demonstrates both the benevolent intentions, and the admirable wisdom of Him " whose hands have made and fashioned us," and who " breathed into our nostrils the breath of life."

The above are only two or three out of a hundred of similar instances, which might be produced to show the benevolent care which has been exercised in arranging and articulating the system of bones, of which the prop-work of the human frame is composed. Were we to enter into an investigation of the actions and uses of the various muscles, the wonderful system of veins and arteries, the action of the heart, stomach, and bowels; the process of respiration, and insensible perspiration, and the system of nerves, glands, lymphaties, and lacteals—a thousand instances of Divine wisdom and beneficence would crowd upon our view, which could not fail to excite the pious and contemplative mind to join in the devotions of the " sweet singer of Israel," '4 I will praise thee ; for I am fearfully and wonderfully made ; marvellous are thy works, and that my soul knoweth right well."—But as I intended to present only a few specimens of the Wisdom of God, as displayed in the construction of the material world, I shall conclude this department of my subject with a single reflection.*

Hovo foolish and ungrateful is it for rational beta/* to overlook the wise and benevolent arrangement*: *f the Creatort in the material universe * How many thousands of human beings pass their existence without once reflecting on ihe numerous evidences of Divine Wisdom and Beneficence, which appear around them, or feeling the least spark of gratitude for their preservation and comforts, to that Being " io whose hand their breath is, and wltose are all their ways!" Yea, how many are there who consider themselves as standing high in the ranks of the Christian profession, who affect to look down, with a certain degree of contempt, on the study of the material works of God, as if it were too gross asubject for their spiritual attainments 1 They profess to trace the wisdom of God in the Scriptures, and to fuel gratitude for his pardoning mercy; but they seldom feel that gratitude which they ought to do for thoso admirable arrangements in their own bodies, and the elements around them, by which their lives are preserved, and their happiness promoted; and even seem to insinuate, that they have little or oothing to do with the contrivances of the God of Nature. They leave it to the gen ius of infidel philosophers to trace the articulations of the bones, the branchings of the veins and arteries, the properties of light, and the composition of ihe atmosphere, while they profess to feast their minds on more sublime and spiritual entertainments. But, surety, such astonishing displays of the wisdom and benignity of the Most High, as creation exhibits, were never intended to be treated by his intelligent offspring with apathy or indifference; and to do so, must indicate a certain degree of-in gratitude towards Him whose incessant energy sustains the whole assemblage of sentient and intelligent beings, and who displays himself, in their construction and preservation, to be u wonderful in counsel, and excellent in working." Shall we imagine, that, because God stands in the gracious relation of our Redeemer, he has ceased to stand in the relation of our Creator and Preserver? Or shall we consider those subjects as unworthy of our attention, which are the theme of the praises of the heavenly host? Rev. iv. II. Can we suppose that the Almighty displayed his infinite wisdom in the curious organization of the human eye, that man—the only being in this world who is endowed with faculties capable of appreciating

• Those who wish to prosecute this subject, particularly that part of It which relates to the contrivuices 0/ Divine Wisdom, whtch appear in the antnul yyftem, will nod ample irratifiration in Nleuwentrt's " Relurfons Khikworher," Vut. 1, and Dr. Fatey*s "Natural Theology." A variety of useful remarks on tins subject will also be found in Ray's "WisUim of God in the Creation," Derham's " PhyUco-Theoiugy," ajtd Bonnet's u Contemplation of Mature."

its structure, and for whose use and entertainment it was intended—should overlook such a wonderful piece of Divine workmanship, and fee) not gratitude for the bestowment of so admirable a gift? Shall we extol the ingenuity displayed in a clock or a wateh, in a chess-player, or a steam engine, and shall we feel no sentiment of admiration at the view of millions of instances of Divine mechanism which infinitely transcend the powers of the human understanding? To act in this manner, as too many are disposed to do, is unworthy of man, both as a Christian and as an intelligent agent. Such was not the conduct of the inspired writers; their spirituality of views did not lead them to neglect the contemplation of any of the works of God. "I will meditate on ull thy works," says the Psalmist, " and talk of all thy doings; I will utter abundantly the memory of thy great goodness, and speak of thy wondrous works." Accordingly we find, that the wonders of the human frame, the economy of the animal and ihe vegetable tribes, the scenery of the "dry land," and of the " mighty deep," and the glories of the heavens, were the frequent subjects of their devout contemplation. They consider them in relation to the unceasing agency of God, by whom they were formed and arranged, and as declaring his Wisdom, Goodness, and Omnipotence: and, with this view, ought all the scenes of the visible creation to be investigated by his intelligent creatures.

We have reason to believe, that it is owing, in part, to want of attention to the Divine wisdom and beneficence,asexhibited in the construction of the visible world, that many professed Christians entertain so vague and confused ideas respecting the wisdom and goodness of Deity, as displayed in the economy of Redemption. The terms, Wisdom, Goodness, and Beneficence, in their mouths, become words almost without meaning, to which no precise or definite ideas are attached; because they have never considered the instances and the evidence of these attribute*, displayed in the material creation. And, if am minds have not been impressed with a sense of the wisdom and beneficence of God, 1:1 those objects which are presented to the external sense, we cannot be supposed to have luminous and distinct ideas of those spiritual objects and arrangements which are removed beyond the sphere of our corporeal organs. For all our ideas, in reks* tion to Religion and its objects, are primarily derived from the intimations we receive of externa! objects, through the medium of our senses; and, consequently, the more clearly we perceive the agency of God, in his visible operations, nV! more shall we be qualified to perceive the wiei*m and harmony of his dispensations, as rtcor&J the volume of inspiration.

We live in a world, all the arrangttasstff which are the effects of infinite Wi*&mv v-,

« ZurückWeiter »