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we live, and move, and have our being ;” and that “in His hand is the soul of every living thing, and the breath of all mankind !"
A great variety of other admirable properties is possessed by the atmosphere, of which we shall briefly notice only the following :-it is the vehicle of smells, by which we become acquainted with the qualities of the food which is set before us, and learn to avoid those places which are damp, unwholesome, and dangerous. It is the, medium of sounds, by means of which knowledge is conveyed to our minds. Its undulations, like so many couriers, run for ever backwards and forwards, to convey our thoughts to others, and theirs to us; and to bring news of transactions which frequently occur at a considerable distance. A few strokes on a large bell, through the ministration of the air, will convey signals of distress, or of joy, in a quarter of a minute, to the population of a city containing a hundred thousand inhabitants. So that the air may be considered as a conveyer of the thoughts of mankind, which are the cement of society. It transmits to our ears all the harmonies of music, and expresses every passion of the soul: it swells the notes of the nightingale, and distributes alike to every ear the pleasures which arise from the harmonious sounds of a concert. It produces the blue color of the sky, and is the cause of the morning and the evening twilight, by its property of bending the rays of light, and reflecting them in all directions. It forms an essential requisite for carrying on all the processes of the vegetable kingdom, and serves for the production of clouds, rain, and dew, which nourish and fertilize the earth. In short, it would be impossible to enumerate all the advantages we derive from this noble appendage to our world. Were the earth divested of its atmosphere, or were only two or three of its properties changed or destroyed, it would be left altogether unfit for the habitation of sentient beings. Were it divested of its undulating quality, we should be deprived of all the advantages of speech and conversation of all the melody of the feathered songsters, and of all the pleasures of music: and, like the deaf
and dumb, we could have no power of communicating our thoughts but by visible signs. Were it deprived of its reflective powers, the sun would appear in one part of the sky of a dazzling brightness, while all around would appear as dark as midnight, and the stars would be visible at noon-day. Were it deprived of its refractive powers, instead of the gradual approach of the day and the night which we now experience, at sun-rise, we should be transported all at once from midnight darkness to the splendor of noon-day: and, at sun-set, should make a sudden transition from the splendors of day to all the horrors of midnight, which would bewilder the traveller in his journey, and strike all creation with amazement. In fine, were the oxygen of the atmosphere completely extracted, destruction would seize on all the tribes of the living world, throughout every region of earth, air, and sea.
Omitting, at present, the consideration of an indefinite variety of other particulars, which suggest themselves on this subject, I shall just notice one circumstance more, which has a relation both to the waters and to the atmosphere. It is a well known law of nature, that all bodies are expanded by heat, and contracted by cold. There is only one exception to this law which exists in the economy of our globe, and that is, the expansion of water in the act of freezing. While the parts of every other body are reduced in bulk, and their specific gravity increased by the application of cold; water, on the contrary, when congealed into ice, is increased in bulk, and becomes of a less specific gravity than the surrounding water, and, therefore, swims upon its surface. Now, had the case been otherwise ; had water, when deprived of a portion of its heat, followed the general law of nature, and like all other bodies, become specifically heavier than it was before, the present constitution of nature would have been materially deranged, and many of our present comforts, and even our very existence, would have been endangered. At whatever time the temperature of the atmosphere became reduced to 32° of the common thermometer, or to what is called the freezing Vol. I.
point, the water on the surface of our rivers and lakes would have been converted into a layer of ice; this layer would have sunk to the bottom as it froze; ano. ther layer of ice would have been immediately produced, which would also have sunk to the former layer, and so on in succession, till, in the course of time, all our rivers, from the surface to the bottom, and every other portion of water, capable of being frozen, would have been converted into solid masses of ice, which all the heat of summer could never have melted. We should have been deprived of most of the advantages we now derive from the liquid element, and, in a short time, the face of nature would have been transformed into a frozen chaos. But, in the existing constitution of things, all such dismal effects are prevented, in consequence of the Creator having subjected the waters to a law contrary to that of other fluids, by means of which the frozen water swims upon the surface, and preserves the cold from penetrating to any great depth in the subjacent fluid; and when the heat of the atmosphere is increased, it is exposed to its genial influence, and is quickly changed into its former liquid state. How admirably, then, does this exception to the general law of nature display the infinite intelligence of the great Contriver of all things, and his providential care for the comfort of his creatures, when he arranged and established the economy of nature !
CIRCLE OF THE SCIENCES, WITH SUITABLE
REFLECTIONS. ASTRONOMICAL SKETCHES.-N0. VI. The velocity of the earth, like that of all the other planets, varies in different parts of its orbit; being most rapid about the Ist of January, and slowest about the 1st of July. The cause of this increase and decrease in the motion of the Earth is the situation of the Sun in respect to the earth's orbit. The orbit of the Earth is elliptical, and the Sun is placed in the lower focus of this orbit, which is 1,377,000 miles from the middle point of the longer axis ; consequently, the earth comes
twice as much, or 2,754,000 miles, nearer the Sun in winter than in summer.
As the Earth passes over a greater portion of the ecliptic in a given time in winter than in summer, there is one fact connected with this circumstance which we ought not to overlook, viz. that our winters are shorter and our summers longer, by six or seven days,* than they would be, if the motion of the Earth in the ecliptic was equal throughout the year. .
The north pole of the Earth appears to be always directed towards the north pole, or the same point of the heavens; but this is not correct in fact. The Earth's axis preserves its parallelism from year to year, with the exception of a very slight and imperceptible variation in that time ; consequently, the axis of the Earth describes a circle in the heavens, the diameter of which is equal to the diameter of the Earth's orbit, or 190 millions of miles. But this amazing extent is only a mere point in comparison with our distance from the fixed stars. · The certainty of all astronomical calculations depends on the parallelism of the axis of the Earth and the equal or uniform motion of its diurnal revolution. And the important science of navigation greatly depends on the same circumstances.
THE ANCIENT AND MODERN HISTORY OF
OF THE GRECIAN MONARCHY. ANCIENT GREECE was bounded on the east by the Ægian sea, now called the Archipelago; on the south by the Cretan or Candian sea ; on the west by the Ionian sea; and on the north by Illyria and Thrace. This country, though limited within such narrow bounds, gave birth to all the arts of war and peace, produced the greatest generals, philosophers, poets, painters, architects, and statuaries that the world ever knew;
• Six days in the leap year, and seven in the common year.
she overcame the most powerful monarchs, and dispersed the largest armies that were ever brought into the field, and at length became the instructer of all mankind.
In the early periods of the world kingdoms and states were inconsiderable: a single city, with a few leagues of land attached to it, was denominated a kingdom. Ancient Greece was divided into several such states, of which
Sicyon is reckoned the oldest, the commencement of which is, by historians, dated 2089 years before the christian era. The founder and first monarch of Sicyon was Ægialeus, who was succeeded by twenty. five kings, whose several reigns together make an epoch of nine hundred and sixty years, and at last became subject to the kingdom of
Argos, which was founded in 1856, B. C. Among the Argive kings was Danaus, from whom the Greeks were called Danai:
ATHENS was formed into a kingdom about three hundred years after the establishment of Argos. Ce. crops, the first king, was by birth an Egyptian; he instituted many wise laws relating to the conduct of life, and the exercises of religious and civil offices. He di. vided the whole country into twelve districts, and esta. blished a court for trying causes, entitled the Areopagus. Codrus, the last of the Athenian kings, is celebrated for having devoted himself to death for his country. Medon, his son, was set at the head of the commonwealth, under the title of Archon, an office which, at first, was held for life, afterwards the Archon's power was limited to ten years, and at last the office was elective every year.
THEBES, the next of the Grecian kingdoms, was founded by Cadmus, to whom is ascribed the honor of inventing sixteen letters of the Greek alphabet. The history and adventures of his posterity, Laius, Iocasta, Edipus, &c. make a principal figure in the tragedies of Eschuylus, Sophocles, and Eurypides. · SPARTA, or Lacedæmon, was instituted by Lelex. Helen, the tenth in succession from this monorih, is