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CHAPTER VIII. Page Chronology—Revolution of the Pole of the Ecliptic—Precession of the Equinoxes—Egyptian Zodiacs, - - - 87

C H A PTE R IX. Signs of the Zodiac-Line of the Apsides—Change of the eccentricity of the Earth's Orbit, - - - - 97 CHA PTE R. X.

The Seasons—Declination of the Sun–Equinoxes—Division of the Earth into five Zones—Sun's Path, - - 105

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Meteorology—Indications of the Weather—Barometer—
Density of the Air—Pressure of the Air—Caswell's Bar-

ometer, - - - - - - - - - 115

CHA PTER II. Winds—Temperature of Valleys—Trade Winds–Monsoons—Hurricanes--The Sirrocco--The Harmattan--The Simóon, - - - - - - - - - 125

C H A P T E R III. o Clouds and Dew—Formation of Clouds—Various kinds of Clouds—Table Mountain, - - - - - - 137

CHAPTER IV. Climate–Distribution of Heat upon the Earth's Surface— Different Lengths of Days—Thermometer—Isothermal Lines—Effect of Climate on Plants and Animals—Table of Temperatures, - - - - - - - 147 CHAPTER V. Optical Phenomena—Color of the Atmosphere—Halo–Mirage—Meteoric Showers—Zodiacal Light—Aurora Borealis, - - - - - * - - a 159



Gradual Elevation of Coasts—Temple of Jupiter Serapis

—Elevation of Coast of Sweden—Earthquake in Cala

bria—In Peru, - - - - - - - C. H. APTER IX.

Atmospheric Causes of Change—Sand Floods-Dunes—
Chemical Influence of the Atmosphere-Disintegration of
Granite, - - - - - - - - -
Vital Causes of change—Coral Animalcules—Brain-stone
Coral—Madrepores—Appearance of Living Corals, -
c H A P T E R x1.
Coral Islands—Atolls—Barrier and Fringing Reefs—Whit-
sunday Island—Bolabola—Formation of Atolls and Bar-
rier Reefs, - - - • -- - - - -

Organic Remains—Infusoria in Flint—Age of the Earth-
Minerals and Fossils—Imbedding and Preservation of Or-
ganic Bodies—Division of the Animal Kingdom, - -

The Granitic Period—Basaltic Columns—Fingal's Cave—
Graptolites--Encrinites—Trilobites--Fossil Fishes—Ferns
—Fossil Crustaceans-The Belemnite--Flora of the Oolitic
Period—Pterodactyle—Close of the first Epoch, - -


Commencement of the second Period—Fossil Foot-steps—

The Labyrinthodon--Dinornis–Plesiosaurus—Ichthyosau

rus—Close of the second Epoch, - - - - - CHAPTER XV.

The Tertiary or third Period—Character of the DepositsFossil Remains—The Deinotherium—Mammoth—Mastodon—Elephant—Megatherium—Irish Elk—Close of the last Epoch, - - - - - - -

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C H A P T E R 1.
Figure of the Earth.

“And still, as sunk the golden Orb of day, The seaman watched him, while he lingered here, With many a wish to follow, many a fear, And gazed, and gazed, and wondered where he went, So bright his path, so glorious his descent.” — Rogers. THE constant and regular succession of day and night, is the first great phenomenon which arrests our attention, when we commence a study of nature. Day after day, we behold the sun, after a definite and well determined period, rising in the east, and ascending the heavens; and no sooner has the blazing orb sunk beneath the western horizon, than we raise our eyes to the blue vault, expecting and beholding the placid stars. Doubtless, the first impression is always, that we are at rest, and that the sun, and all the stars of heaven, are slowly, and forever, revolving around us. A thoughtful consideration of the phenomena which attend the regular return of day and night, will soon convince us that this conclusion is erroneous, and will point out to us the true solution of the grand problem. Let us go upon some eminence when evening draws near, and watch the successive changes which usher in the night. The red orb of the sun, shorn of his lustre, his ruddy beams scarce penetrating the mists which creep over the surface of the earth, sinks gradually beneath the wave, or distant hills; a ruddy glow illumines the western sky,

“Twilight's soft dews steal o'er the village green,”

slowly the light fades away, fainter and fainter, giving place to B

serene night, and now the stars, which the brilliancy of day had eclipsed, shine forth in all their splendor, and perhaps that fairest one of them all, the evening star, adorns the western sky. As we look over the heavens, we notice here and there a group, or as the astronomer calls them, a constellation, with which we have been familiar from childhood. If we look upon the winter sky, we recognize Orion, with his bright belt, and the Pleiades or seven stars, or turning to the north, the great dipper or Charles’ wain, being a part of the constellation “Ursa Major,” or the “Great Bear.” As the eye wanders over these familiar objects, another sight bursts upon the delighted vision. The full-orbed moon rises majestically over the eastern hills, and in the increasing light, the lesser stars fade away. The evening star, no longer brilliant, is now ready to set below the western horizon, and stars, which at the commencement of night, were to the east of the meridian, are now in the mid heaven. If we turn to the north we find a change there, the cluster or group called the dipper, which we will suppose, at the commencement of our observation was almost parallel with the horizon, as shown in this figure, has moved

eastward, and evidently performed a part of a revolution about some unknown centre. If we prolong our observations we find this group, and all the rest of the heavens apparently revolving around one star, which seems not to move at all. This star is called the pole, or polar star, and is nearly in a line with the two bright stars at the end of the dipper as shown at a and bin the above diagram, and about five times their distance, from the nearest one. Meanwhile, the lunar orb, with all its beautiful diversity of

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