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collect that the air is not a solid but a fluid body. Throw a stone into a smooth stream of water, and there will take place undulations, which will be extended more or less according to the degree of force with which the stone was impelled. Conceive then that when a word is uttered in the air, a similar effect takes place in that element as is produced by the stone in the water. During the action of speaking, the air is expelled from the mouth with more or less force; this communicates an undulatory motion to the external air which it meets; and these undulations of the air entering the cavity of the ear, the external parts of which are peculiarly adapted to receive them, strike upon the tympanum or drum, by which means it is shaken, and receives a trembling motion: the vibration is communicated to the malleus, the bone immediately in contact with the membrane, and from it to the other bones; the last of which, the stapes or stirrup, adhering to the fenestra ovalis, or oval orifice, causes it to vibrate; the trembling of which is communicated to a portion of water contained in the cavity called the vestibulum, and in the semicircular canals, causing a gentle tremor in the nervous expansion contained therein, which is transmitted to the brain: and the mind is thus informed of the presence of sound, and feels a sensation proportioned to the force or to the weakness of the impression that is made.
What great cause we have to rejoice in possessing the faculty of hearing! for without it our state would be most wretched and deplorable; in some respects more sorrowful than the loss of sight: had we been born deaf, we could not have acquired knowledge sufficient to enable us to pursue any art or science. Let us never behold those who have the misfortune to be deaf, without endeavouring better to estimate the gift of which they are deprived, and which we enjoy, or without praising the goodness of God, which has granted it to us; and the best way we can testify our gratitude is to make a proper use of this important blessing.
The Milky Way.
IF we observe the heavens during a clear night we discover a pale irregular light, and a number of stars, whose mingled rays form the luminous tract which is called the Milky Way. These stars are at too great a distance to be perceived by the naked eye; and amongst those which are visible with a telescope, there are spaces apparently filled with others in immense numbers, though not distinctly perceptible through a telescope. Though the number already discovered is prodigious, if we could make our observations from another side of the globe, nearer to the an tarctic pole, we should be able to make still more discoveries, and see a number of stars which have never appeared upon our hemisphere; and yet we should not even then be able to discover the half, or the thousandth part, of those radiant bodies which shine in the immense firmament of heaven.
All the stars which we perceive in the milky way appear no more than so many luminous points, though each one may be much larger than the whole terraqueous globe. If we use instruments of the utmost power, they never appear larger than when seen by the naked eye. Were an inhabi. tant of this earth to ascend into the air one hundred and sixty millions of miles, the fixed stars would still appear no larger than luminous specks. Incredible as this assertion may appear, it is not a chimerical idea, but a fact which is effectively proved; for about the 10th of December we are more than one hundred and sixty millions of miles nearer the northern part of the heavens that we are on the 10th of June; and yet we never perceive any increase of magnitude in the stars.
The milky way, though little, compared with the rest of the heavens, is amply sufficient to manifest the grandeur of the Supreme Being; and each one of the stars we there discover displays the wisdom and goodness of the Almighty. And what are these stars in comparison of the immense number of worlds revolving in the firmament of heaven?
Reason herself is confounded in the contemplation, and lost in admiration; we can only wonder and adore.
Often then, as we behold the starry sky, let us raise our souls to thee, O adorable Creator! and confess with shame how seldom we have thought of thee; how little we have reverenced thy grandeur or praised thy majesty! Pardon our insensibility, and forgive our ingratitude, O God! Loose these souls bound by earthly ties, and raise them to thyself, O Creator of heaven and earth! Suffer us to humble ourselves at thy feet, deeply convinced of our littleness and unworthiness! Then may we be comforted in our contrition with the glorious hope, that our redeemed souls will hereafter soar beyond the region of the stars in endless felicity!
Germination of Plants.
THE vegetable kingdom is a vast field, where the attentive observer may contemplate the boundless power and omnipotent wisdom of the Creator. Though we should live upon the earth for the space of a hundred years, and though we were to dedicate every day to the study of a particular plant, at the end of our career there would still remain many things that we had not perceived, or had not been able sufficiently to observe. Let us reflect upon the production of plants, and examine their internal structure, and the conformation of their different parts; let us reflect upon the simplicity and diversity discoverable in them, from the least blade of grass to the most lofty oak; and endeavour to become acquainted with the nature of their growth, the manner in which they are propagated, how they are preserved, and the different properties by which they are useful to the animal creation. Each of these articles will sufficiently employ our faculties, and teach us the infinite power and merciful goodness of the Creator. We shall every where discover with admiration the most wonderful order and incomprehensibly beneficial designs,
Though we were to know no more of plants than the phe
nomena which every eye may distinguish; though we only knew that a grain of corn, when sown in the earth, at first shoots forth a root into the soil; then a stem upwards, which pierces the surface, and bears branches, leaves, and fruit, in which are included the germs of new plants; we should yet discover sufficient to convince us of the profound wisdom of the Creator. Let us attentively consider all the changes which a grain of wheat undergoes in the earth: it is sown at a certain time, which is all we can do to assist its progress; but nature is more active. As soon as it has acquired the necessary degree of humidity from the earth, it swells; the external coat or skin which concealed the root, stem, and leaves, opens; the root bursts forth and penetrates into the earth, where it derives nourishment for the stem, which now makes an effort to raise itself up above the surface of the ground. When it has sprung up, it gradually increases till it has arrived at its proper height; it then unfolds its leaves, which at first are white, then yellow, and at length are tinged with a beautiful green. If we confine ourselves to the examination of this grain of corn, so necessary to our subsistence, what admirable wisdom we shall observe! Immediately as the tunic which enclosed the germ is rent, and the root has penetrated the earth, the stem ventures to spring up in the form of a fine and delicate filament, which, however feeble it may appear, is able to contend with the inclemency of the air. It gradually increases in size till it produces the ear of corn, the sight of which is so grateful, and where the fruit is enclosed in leaves which serve as a sheath till it is strong enough to break through them.
The fields where corn is sown may serve to remind us of fields sown with a very different kind of seed. We may regard our bodies, when quietly deposited in the earth, as seeds which are to spring up and be matured in eternity. We have as little reason to expect that a grain of wheat placed in the ground will produce an ear of corn, as that our bodies reduced to dust shall become glorious bodies of light and immortality. The time will come, when the seed shall unfold itself, our dust will be reanimated, and the righteous will live in Christ. In that great day, what will become of you who despise our faith? It is true, our bodies must dissolve and turn to dust; but they will not always
remain under the influence of death. The soul of the just man made perfect will repose from the labours of this life, in the bosom of his God, full of happiness and adoration. Eye hath not seen, nor ear heard, neither hath the imagination of man conceived, a state of salvation so blessed and glorious as this!
The azure Colour of the Sky.
To judge from the first impressions of our senses, we might suppose that the heaven above us was an immense vault of blue studded with brilliants; such an opinion, however, will only be retained by the most ignorant of men, though many with some title to understanding have very absurd notions of the sky. The reason why it appears of an azure colour is to be ascribed to the atmosphere not being perfectly transparent. Were it possible to ascend very high above the surface of the earth, the air would be found much more rare, till, if we were to ascend still higher, it would become incapable of assisting in respiration, and at length would entirely cease, when we should have reached the region of pure ether.
The higher the mountains are which we ascend, the lighter does the atmosphere become, and the azure colour of the heavens fainter. And if it were possible to ascend to the regions of pure ether, the blue colour would entirely disappear, the sky would appear black as night; for so do those objects appear which do not reflect the rays of light. Consequently, if the air which surrounds us was as transparent as ether, the sky could not appear blue. The air is filled with innumerable minute particles, which when illumined by the sun, receive a motion, in consequence of which new rays are produced; and those particles, of themselves abscure, become visible to us when they are thus illumined. Their colour is blue; hence a forest, which appears green when we are nigh to it, seems to be more and more blue as we recede from it. However pale and subtile are the blue rays