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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 rabbits the eyes are very convex and prominent, so that they can see nearly quite round them, whereas, in dogs which pursue these animals, the visual organs are placed more in the front of the head, to look rather before, than behind them.-Some animals, as cats and owls, which pursue their prey in the dark, have the pupil of their eye so formed as to 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 butterfly, whose eyes are incapable of motion, have several thousands of small transparent globes set in a convex hemisphere, every one 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. But, 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 of 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 mechanism 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 the nature of a hinge, by which a vertical motion, or a motion upwards and downwards is produced. A horizontal motion, or a motion towards the right hand or the left, is produced by a pivot moving in a socket; so that, by these two motions, the telescope can be made 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 requiste 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 every direction, is 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 combined with the former.
For example, let any person, for a moment, consider the joints of his fingers, and compare them with the joints 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 ; but 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 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 combined with an articulation which produces nearly the same effect as a pivot moving in a socket. Now, had the joints of the fingers 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 the 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, 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 finger is composed of three bones, connected together by articulations, muscles, and ligaments. If, instead of three, each finger were composed of only one bone, it would be quite impossible for us to grasp a single object.
The same admirable contrivance may be perceived in the movements of which the Head is susceptible. It was requisite, in order to our convenience and comfort, that we should be enabled to 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 whole body. Accordingly we find, that both these motions are provided for, in the manner in which the head is connected with the vertebræ. 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 backward and forward; 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 lying 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 propwork 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, lymphatics, 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," "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.*
* Those who wish to prosecute this subject, particularly that part of it which relates to the contrivances of Divine Wisdom, which ap
How foolish and ungrateful is it for rational beings to overlook the wise and benevolent arrangements of the Creator, in the material universe! How many thousands of human beings pass their existence without once reflecting on the 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" in whose hand their breath is, and whose 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 a subject for their spiritual attainments! They profess to trace the wisdom of God in the Scriptures, and to feel gratitude for his pardoning mercy; but they seldom feel that gratitude which they ought to do, for those admirable arrangements in their own bodies, and in the elements around them, by which their lives are preserved, and their happiness promoted; and, even seem to insinuate, that they have little or nothing to do with the contrivances of the God of Nature. They leave it to the genius 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 the atmosphere, while they profess to feast their minds on more sublime and spiritual entertainments. But, surely, 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 and indifference; and to do so, must indicate a certain degree of base ingratitude 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 "wonderful in counsel, and excellent in working." Shall we imagine, that, because God stands in the gracious rela
pear in the animal system, will find ample gratification in Nieuwentyt's "Religious Philosopher," Vol. I. and Dr. Paley's "Natural Theology." A variety of useful remarks on this subject will also be found in Ray's "Wisdom of God in the Creation," and Derham's "Physico-Theology."