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of piety, has it brought to maturity! May the Divine grace be so poured into our hearts, that we may ever feel its quickening, saving influence !
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 every where 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 majestic 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 Herschell. Of these the nearest to the sun is Mercury; it is much smaller than the earth, its diameter being only 2600 miles, and from its proximity to the sun, round which
* Discovered first at Bath, March 17, 1781, by the philosopher whose name it bears,
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 51,000 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 travelling round him in 686 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 ours, and the sun appears to him but half as large as 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 surrounded 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 five hours of our time. He
is nearly six hundred times larger than our earth, his díameter 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 of 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, which renders it impossible for them to be illumined by his rays: 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.
Dr. Herschel has discovered two other moons belonging to Saturn, so that there are now seven moons attendant on that planet.
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 encircling 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 pretend 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 ?*
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 sufficiently 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 shewn us, that objects, invisible to
*As the above account differs from the original more than even a liberal translation will authorize, 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.
the naked eye, exist, having figure, extension, and different parts: some examples of which we shall produce, that we may have more causes to admire and praise the wisdom 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 magnify objects millions of times more than their natural size, we can discover, in the grains of sand, a new animal world; for within their cavities dwell various insects. In cheese are found innumerable animalculæ, called mites, which to the naked eye appear as points, whilst seen through a microscope they are found to be insects of a very singular form and structure; they have not only a mouth, eyes, and feet, but their transparent body is covered with long hairs, sharp, and formed like needles.* In the vegetable kingdom we are presented with a thick forest of trees and plants, bearing leaves, branches, flowers, and fruits; the rudiments of all which beautiful objects were once hidden beneath the mold: little as we should have expected to find these in such a bed, as little should we have supposed the dust upon the wings of a butterfly to be minute feathers, or the bloom of a peach to be a collection of insects, had not the microscope furnished us with this intelligence.
Thus we see the power of God is great in those things which ignorance makes us regard as minute; for however small the minutest animalcule appears to us, we have reason to believe there are objects which appear to it as small as it does to us. By the view which we have just been taking, we shall also find the subjects of nature to be much more numerous than we had imagined. Though we are acquainted with many thousand species of plants and insects,
*The view of a frog through a solar microscope is strikingly beautiful; from the transparency of its skin, the blood is seen to circulate in the vessels in a manner indescribably wonderful and brilliant. The physiologist is likewise indebted to the microscope for his more intimate kuowledge of the red particles of the blood; but, owing to a difference of glasses, or some imperfection in the optic nerve, there is yet a dispute whether they are perfectly globular, or circular as to circumference with a plane superficies, in the manner of a flat shilling.-E.