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these different changes may be traced, by attending to her apparent positions from time to time, with respect to the fixed stars.

A dark shadow is occasionally seen to move across the face of the moon, which obscures her light, and gives her the appearance of tarnished copper. Sometimes this shadow covers only a small portion of her surface, at other times it covers the whole of her disk for an hour or two, and its margin always appears of the figure of a segment of a circle. This phenomenon, which happens, at an average, about twice every year, is termed an eclipse of the moon. It is produced by the shadow of the earth falling upon the moon, when the sun, the earth, and the moon are nearly in a straight line; and can happen only at the time of full moon. Sometimes the moon appears to pass across the body of the sun; when her dark side is turned towards the earth, covering his disk either in whole or in part, and intercepting his rays from a certain portion of the earth. This is called an eclipse of the sun, and can happen only at the time of new moon. In a total eclipse of the sun, which seldom happens, the darkness is so striking, that the planets and some of the larger stars are distinctly seen, and the inferior animals appear struck with

terror.

Again, if on a winter's evening, about six o'clock, we direct our view to the eastern quarter of the sky, we shall perceive certain stars just risen above the horizon; if we view the same stars about midnight, we shall find them at a considerable elevation in the south, having apparently moved over a space equal to one half of the whole hemisphere. On the next morning, about six o'clock, the same stars will be seen setting in the western part of the sky. If we turn our eyes towards the north, we shall perceive a similar motion in these twinkling orbs; but with this difference, that a very considerable number of them neither rise nor set, but seem to move round an immovable point, called the north pole. Near this point is placed the pole star, which seems to have little or no apparent motion, and which, in our latitude, pears elevated a little more than half way between the northern part of our horizon and the zenith, or point above our heads. A person who has directed his attention to the heavens for the first time, after having made such observations will naturally enquire-Whence come those stars which begin to ap

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pear in the east? Whither have those gone which have disappeared in the west? and, What becomes, during the day, of the stars which are seen in the night?—It will soon occur to a rational observer, who is convinced of the roundness of the earth, that the stars which rise above the eastern horizon come from another hemisphere, which we are apt to imagine below us, and when they set, return to that hemisphere again; and that the reason why the stars are not seen in the day-time, is not because they are absent from our hemisphere, or have ceased to shine, but because their light is obscured by the more vivid splendour of the sun. such observations we are led to conclude, that the globe on which we tread is suspended in empty space-is surrounded on all sides by the celestial vault-and that the whole sphere of the heavens has an apparent motion round the earth every twenty-four hours. Whether this motion be real, or only apparent, must be determined by other considerations.

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Such general views of the nocturnal heavens, which every common observer may take, have a tendency to expand the mind, and to elevate it to the contemplation of an Invisible Power, by which such mighty movements are conducted. Whether we consider the vast concave, with all its radiant orbs, moving in majestic grandeur around our globe, or the earth itself whirling round its inhabitants in an opposite direction-an idea of sublimity, and of Almighty energy, irre sistibly forces itself upon the mind, which throws completely into the shade the mightiest efforts of human power. The most powerful mechanical engines that were ever constructed by the agency of man, can scarcely afford us the least assistance in forming a conception of that incomprehensible Power which, with unceasing energy, communicates motion to revolving worlds. And yet such is the apathy with which the heavens are viewed by the greater part of mankind, that there are thousands who have occasionally gazed at the stars for the space of fifty years, who are still ignorant of the fact, that they perform an apparent diurnal revolution round our globe. Dick's Christian Philosopher.

1. What does Astronomy teach us? 2. What strikes us with wonder, in the objects it presents to our view?

3. What do we behold on looking to the sky?

4. Describe the daily course of the sun in our hemisphere ?

5. How will the sun rise and set, with regard to us, on the 21st of March? 6. How does he rise and set, in our part of the world, in June and December?

7. What is the length of the solar year? 8. In what time does the moon revolve round the earth?

9. In what part of the heavens does the new moon appear?

10. Where does the moon appear when full?

11. How does the moon move after becoming full?

12. Describe an eclipse of the moon. 13. What causes an eclipse of the moon, and when only can it happen?

14. What is an eclipse of the sun, and when does it happen?

15. If you watch the stars on a winter's evening, how will they seem to have moved, between six o'clock and twelve?

16. What about the motion of the stars in the northern part of the sky?

17. What about the position, and motion, of the pole star?

18. Whence come the stars that appear in the east?

19. Whither have those gone that disappear in the west?

20. Why are the stars not seen in the day time?

21. Are not the wisdom, power, and goodness of God, clearly manifested in the starry heavens?

22. Who is called the Sun of Righteous. ness, and why is he so called?

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THE manner in which the blood-vessels are disposed in the human body bears some resemblance to the arrangement of the pipes by which a great city is supplied with water. don is supplied by means of an engine contrived for the purpose of distributing the water of the New River through the city. Large trunks are carried from this machine in different directions; smaller pipes branch out from these trunks into streets, lanes, and alleys; still smaller ones issue from them, and convey the water into private houses. So far the resemblance is complete. These water pipes represent the arteries which carry the blood from the heart to the extremities of the body; but in the human body another contrivance was necessary. The citizens of London may use the water or waste it as they please; but the precious fluid conveyed by the arteries to the ends of the fingers must be returned to the heart; for on its unceasing circulation our health depends.

In order to effect this purpose, another set of pipes is prepared, called veins, which joining the extremities of the arteries, receive the blood from them, and carry it back again to the heart. The veins present the same general appearance as the arteries; but as it is the office of the arteries to distribute the blood, so it is that of the veins to collect it.

Through them it flows back to the heart in a manner just the reverse of that in which it sets out; the minute veins unite in larger branches, the larger branches unite in still larger trunks, till the collected blood is at length poured into the heart through one opening.

The engine that works this curious machinery is the heart. The heart is composed of four cavities. Like other muscles, it has the power of contracting; and when it contracts, the sides of its cavities are squeezed together, so as to force out any fluid the heart may at that moment contain. This purpose being effected the fibres relax, the heart once more becomes hollow, and as it dilates, the blood pours into the cavities from the large vein which brings it back to the heart. The next contraction forces the blood into the arteries, the quantity thus impelled being always equal to that which has just been received; and thus this wonderful organ goes on, alternately contracting and dilating itself, four thousand times in an hour. Month after month, year after year, it goes on without weariness or interruption, conveying renewed strength to every part of the body. The two largest cavities of the heart, which send out the blood to the arteries, are called ventricles; the two smallest, which receive it from the veins, auricles. All the arteries are furnished with valves that play easily forward, but admit not the blood to return to the heart.

In all this there is abundant evidence of wise contrivance. The blood in going out from the heart, is continually passing from wide tubes into those which are narrower; in coming back, it passes from narrow vessels into wider; consequently the blood presses the sides of the arteries with greater force than it acts against the coats of the veins. To prevent any danger from this difference of pressure, the arteries are formed of much tougher and stronger materials than the veins. This is one difference between the two; there is another still more strikingly illustrative of the care of the Great Artificer. As a wound in the arteries, through which the blood passes with such force from the heart, would be more dangerous than a wound in the veins, the arteries are defended, not only by their stronger texture, but by their more sheltered situation. They are deeply buried among the muscles, or they creep along grooves made for them in the bones. The under side of the ribs is sloped and furrowed, to allow these important tubes to pass along in safety; and in the fingers,

which are liable to so many casualties, the bones are hollowed out in the inside like a scoop. Along this channel the artery runs in such security, that you might cut your finger across to the bone without doing it any injury. Mrs. Hack.

1. What does the arrangement of the blood vessels in the human body resemble?

2. Describe the manner in which London is supplied with water.

3. Name the vessels which distribute the blood through the body.

4. What may the citizens of London do with the water if they please?

5. May we waste the blood, the precious fluid, and why not?

6. What office do the veins fulfil?

7. Do the arteries increase or diminish in size from the heart to the extremities? 8. Point out the difference between the arteries and the veins in this respect.

9. Describe the heart, and show in what way it sends the blood out.

10. How is the blood received back into the heart?

11. How many contractions and dilatations of the heart take place in an hour?

12. Name the two larger and the two smaller cavities of the heart.

13. How is the blood prevented from flowing back through the arteries?

14. What provision is made against the arteries being burst by the pressure of the blood?

15. Whether would a wound in an artery or a vein be the more dangerous? 16. How are the arteries placed in the muscles, in the ribs, and in the fingers?

17. Are not the wisdom and goodness of God strikingly manifested in all these arrangements?

18. Repeat to me the words of Psalm cxxxix. 13th and 14th.

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On the 14th September, 1812, while the rear-guard of the Russians were in the act of evacuating Moscow, Napoleon reached the hill called the Mount of Salvation, because it is there where the natives kneel and cross themselves at first sight of the Holy City.

Moscow seemed lordly and striking as ever, with the steeples of its thirty churches, and its copper domes glittering in the sun; its palaces of Eastern architecture mingled with trees, and surrounded with gardens; and its Kremlin, a huge triangular mass of towers, something between a palace and a castle, which rose like a citadel out of the general mass of groves and buildings. But not a chimney sent up smoke, not a man appeared on the battlements, or

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