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JANUARY XII.

Contemplation of the Heavenly Bodies.

THE heavens present to our view, in the night season, a scene of grandeur and sublimity, which forcibly impresses the attentive observer of nature. But how few are capable of receiving the great and noble ideas which the contemplation of the firmament calls forth in a philosophic mind! How few even observe it at all! This, I imagine, can only proceed from ignorance; for it is impossible to take an extensive range through nature, and view the majestic objects everywhere presented, without at once being led through nature up to nature's God, and feeling the power of the mind expand in our vast flight through the regions of space, till we are lost in admiration and rapture, and feel a celestial radiance illume our souls. Oh that every human being would partake of this Divine pleasure! that they would elevate their thoughts beyond the confines of earth, and ranging above the spheres, repose on heaven! It is enough merely to name those immense bodies, each in itself a world revolving in space, to fill the mind with awe and astonishment at the mighty power of the Creator.

In the centre of the planetary system, the Sun, more than a million times larger than our earth, and at the distance of 82 millions of miles, rolls his ma. jestic orb, round which revolve seven planets with their attendant satellites, all deriving their lustre from the central luminary. These planets are known to the astronomers by the names of Saturn, Jupiter, Mars, Venus, the Earth, Mercury, and Herschel.* Of these the nearest to the sun is Mercury; it is much smaller

* Discovered first at Bath, March 17, 1781, by the philosopher whose name it bears,

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than the earth, its diameter being only 2600 miles, and from its proximity to the sun, round which it performs its course in eighty-eight days, rolling at the rate of 95,000 miles an hour, is seldom visible to our eye: the light and heat it derives from the sun are nearly seven times as great as ours, being distant from that luminary only 32 millions of miles. Next comes Venus, completing her revolution round the sun in about seven months, at the computed distance of 59 millions of miles; she is larger than our earth, and shines when west of the sun as a morning star, and when east as an evening star, with astonishing splendour, moving hourly in her orbit 69,000 miles. The third circle is the orbit of the earth, revolving round the sun at the rate of 58,000 miles an hour, which, though little more than half as swift as the motion of Mercury in his orbit, is one hundred and twenty times swifter than that of a cannon-ball. The earth's diameter is 7970 miles, and the moon rolls round it as an attendant satellite, performing her course in 29 days, 12 hours and 44 minutes. The moon's diameter is 2180 miles, and her distance from the earth's centre 240,000. The planet next in order is Mars, about 125 millions of miles distant from the sun, and travel. ling round him in 636 days and 23 hours, at the rate of 47 millions of miles every hour. The diameter of Mars is 4444 miles, his quantity of light and heat equal but to half of our's, and the sun appears to him but half as large to us. The fifth, and the largest of all the planets, is Jupiter, distant from the sun 426 millions of miles, and going every hour in his orbit 25,000 miles. He finishes his annual period in 11 of our years, 314 days, and 12 hours. He is above one thousand times larger than our earth, and is sur rounded by faint substances called belts; they vary considerably in appearance, and sometimes disappear altogether; hence they have been supposed to be

clouds. Four moons revolve round the planet Jupiter, so that scarcely any part of his immense orb remains unenlightened, except the poles, whence only the farthest moons can be seen; but light is there least required, because the sun constantly circulates in or near the horizon, and may be kept in view of both poles by the refraction of Jupiter's atmosphere. Saturn is about 780 millions of miles distant from the sun, and travelling at the rate of 18,000 miles every hour, performs his annual circuit in 29 years, 167 days, and 5 hours, of our time. He is nearly six hundred times larger than our earth, his diameter being 67,000 miles; and he is rounded by a broad ring, round the outer circumference of which revolve five attendant moons. * The sun shines on one side Saturn's ring for nearly fifteen years without setting, and as long on the other in its turn. The last known planet in our system is Herschel, distant from the sun about 1565 millions of miles, and performing his annual circuit in 83 years, 140 days, and 8 hours, of our time, at the rate of 7,000 miles an hour. His diameter being 34,000 miles, he is about eighty times larger than our earth. Dr. Herschel has discovered six attendant moons, and supposes there may be more.

Such is the stupendous grandeur of the planetary system; yet the sun, with all his accompanying planets, forms but a very small part of the universe. Each star, which to us appears scarcely larger or more brilliant than the diamond, equals the sun in magnitude and in splendour, and is in itself a world, and the centre of a planetary system. That they shine with their own and not a borrowed light is demonstrable by their immense distance from the sun,

* Dr. Herschel has discovered two other noons belonging to Saturn, so that there are now seven moons attendant on that planet.

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which renders it impossible for them to be illumined by his rays a cannon-ball shot off from the sun would not reach the nearest fixed star in 600,000 years; hence each may be considered as a sun and he who imagines that such glorious luminaries were formed to shine with an ineffectual light, can have but a very contracted idea of the almighty power and wisdom. The number of stars in either hemisphere visible to the naked eye is not more than a thousand; with the assistance of a good telescope three thousand may be perceived, and, could better instruments be procured, there is every probability of thousands more existing; nay, some very profound philosophers have supposed there are stars at such inconceivable distances, that their light has not yet reached the earth since its creation, although the velocity with which light passes is a million times greater than that of a cannon-ball. Thus, though a man may measure the universe with his telescope, he can form only a very inadequate idea of its amazing extent.

What a noble, what an august subject for meditation! Though the mind of man cannot yet bear to soar with the steady flight of the eagle through the boundless regions of space; though he cannot yet grasp within his span the sublime view of orb encirc ling orb, each in itself a luminary, multiplied without end, attended by millions of worlds, all revolving in matchless order, and harmonious regularity, each in his silent course, with varied motion; some whirling with a rapidity our senses cannot conceive, others less distant performing their circles with less velocity; and all these worlds containing myriads of intelligent beings in different states of felicity and perfectibility.

If then the utmost stretch of the human faculties, the utmost vigour of our reason, cannot comprehend the totality of these works, nor our imagination expand even beyond our own system, how can we pre

tend to scan that Almighty Being, at whose word order arose out of confusion, chaos was converted into elements, and the starry spheres began to move through the heavens ?*

JANUARY XIII.

Discoveries which have been made by the Microscope.

THE wonders of nature are displayed in the minutest as well as in the largest objects; whether we consider the structure of the mite, or that of the towering elephant, we shall find her alike excellent; she has formed them both with the same degree of propriety of construction. It is our senses which are not suffi ciently acute to perceive the organization of very small bodies, which often escape our observation, unless we have recourse to foreign assistance. The microscope has opened to us a new world of insects and vegetables; it has shown us, that objects, invisible to the maked eye, exist, having figure, extension, and dif. ferent parts; some examples of which we shall produce, that we may have more causes to admire and praise the wisdom and power of God. Every grain of sand when examined by the naked eye appears round, but with the help of a glass we observe each grain differs from the other, both in size and in figure: some of them are perfectly round, others square, some conical, and the major part of an irregular form. What is still more astonishing, by microscopes, which

* As the above account differs from the original more than even a liberal translation will authorise, it is right to state, that considerable errors were found, and had been continued by the preceding translators; to correct which, in the present edition, the works of Newton, of Ferguson, and of Euler, have been consulted.-E.

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