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PREFACE,.

The importance of the sciences of Astronomy and Geology, is acknowledged by every one. Few, however, find sufficient leisure to bestow upon these subjects much attention. They look upon the ponderous tomes which men of science have from time to time prepared, with a sort of indifference, as too learned for them. And yet, show any of these, a curious star in the heavens; tell them of the wonders revealed by the telescope; exhibit to them, the impression of a fish in sandstone, or chalk; or show them through a microscope, the curious and distinctive structure of fossil teeth, or the infusoria in a fragment of flint; and they will give willing attention. Since, then, the subjects themselves are so interesting, so profitable, and withal harmless, we have endeavored—with what success will hereafter appear— to supply a desideratum long felt. The object of the present volume is to present in a popular manner, so much of Astronomy, Meteorology, and Geology, as seemed desirable for everyone to know. While no pretensions are made to scientific accuracy, yet it is believed that the book will be found worthy of an attentive perusal. There is little to be gained by merely glancing here and there at a page; the knowledge thus obtained, if any, will be small, and soon lost. The attentive reader will, if the book be worth perusing at all, find sufficient to amply repay for the time thus spent. It should hardly be necessary for anyone at this late day, to offer an apology in behalf of Geological studies, because of the fancied contradictions to the Mosaic chronology. Writers on this subject heretofore, have spent no little pains, in what we may well term, endeavoring to “make darkness visible.” So apologies were once offered for Astronomy, when that noble science , taught the diurnal and annual motions of the earth. We have felt called upon to make no such apology, but simply to state the A*

facts, well convinced that true philosophy and religion go hand in hand, and that if “an undevout astronomer is mad,” so must be an undevout geologist. How vast, and how ennobling the ideas of Creative Power and Wisdom, which these sister sciences afford. The mind is overwhelmed by the immensity of creation, whether itstrives to reach beyond the faintest and fartherest star yet discovered through optic glass, or whether it endeavors to reckon the years elapsed since the first granite rocks upreared their rugged steeps amid the primeval waters. Though we have gazed for whole nights at those dim streaks of nebulous matter in the heavens, at the planets, and revolving stars, when there were companions with us, no longer upon earth; and though we have split open the sandstone shales, and picked out the fossil shells, and looked for hours at little fragments of fossils through the microscope, we do not feel our time as wasted, or wholly spent in vain, if we may be the means of communicating to others a knowledge of these pleasant subjects. However imperfect the execution of our work may be, yet to it we have given long and patient attention. We cannot claim much merit for originality. Among the host of scientific men whose lives have been spent in original investigations, it would be strange could we not find better illustrations than our own; we are still but learners. Should the present attempt to produce a popular work upon Astronomy and Geology prove successful, it is anticipated following it up with a volume upon the planets and stars; for in the present, only so much of Astronomy is presented as is necessary to understand the motions and general phenomena of our earth. The chapters on fossil remains are not as many as might seem desirable; perhaps we may more perfectly and fully review the same subjects hereafter in another volume. It is but right to say that the engravings have all been executed in this city by Mr. J. Brainerd; and when we add that they are not from transfers, but from pencil drawings, they will be acknowledged as very creditable specimens of the artist’s skill. Cleveland, August, 1848.

INTRODUCTION,

It would be difficult for us to name a study more interesting than a history of the Earth, past and present; for by a peculiar and distinct chain of causation, it unites the present with the remote past; constantly urges us to look for the beginning of that state of things we have been contemplating; conducts us to the boundaries of physical science, and even gives us a glimpse of the regions beyond.

The Astronomer looks upon the heavens as the type of eternity and immortality. The crystal spheres and orbs which he once imagined to exist, are, so far as stability and uniformity are concerned, now no longer necessary. A few simple motions, results of one law, controled by one Power Divine, sustains the mighty fabric. The Geologist looks upon the heavens and upon the earth as but everlasting; he comprehends that a thousand changes may come over them, while still they move in their grand circles. To him the present configuration of land and sea is but one of the many changes through which the globe has passed, and he is prepared to admit that the whole human race may be swept away, and a new creation succeed; —such catastrophes have occurred. We ask in vain, whether other worlds are inhabited; no voice comes from those distant orbs to tell us of life, no eye can penetrate so far; we turn then with a renewed zeal to study “the science of the changes which have taken place in the organic and inorganic kingdoms of nature,” as developed on the surface of our own planet. The beginning; where shall the beginning be 7 We endeavor in vain to penetrate the almost sepulchral stillness and darkness of the primeval world, and trace with certainty the origin of things. All that we can possibly know is the simple truth—“In the beginning, Jehovah created the heavens.and the earth.” Certainly there was a day — Geology demonstrates this — when nothing but barren rock and wide spread waters covered the globe. Who but Jehovah called into being the successive races of animal and vegetable life, which have flourished and died? Whose eye but Jehovah's has seen the myriads of revolutions during which the immense fossil-bearing beds were deposited? We cannot comprehend these things; “Our noisy years seem moments in the being Of the etermal silence.”

The granite pebble which we roll over, heedless and careless, is older by millions of years than the first created of our race; and when was that being created 7 Questions like this, we are forced to say, we can no more answer, than we can tell the form, and number, of the inhabitants of the evening star.

“But though philosophers have never yet demonstrated, and perhaps never will be able to demonstrate, what was that primitive state of things in the social and material worlds from which the progressive state took its first departure; —they can still, in all the lines of research, go very far back; — determine many of the remote circumstances of the past sequence of events; — ascend to a point which from our position at least, seems to be near the origin; —and exclude many suppositions respecting the origin itself.” And this is the boundary of human knowledge.

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Rotundity of the Earth—Apparent motion of the Sun—An-
gles—Measurement of a Degree, - - - -

- CHA PTER II.

Apparent motions of the Planets—Ptolemaic System—
Measurement of Angles—Diurnal revolution of the Earth
–Copernican System—Phases of Venus—Religion and
Philosophy, - - - - - - - -

- C HAPTER III.

Parallax—-Measurement of Distances—Distance of the
Moon, how determined—Distance of the Sun—Immensi-
ty of Creation, - - - - - - - -

CHAPTE R IV.

Time—Dials and Clepsydrae—Siderial Day—Transit Instru-
ment—Geology and Astronomy, - - - -

C HAPTE R. V.

The Calendar—Length of the Year—The Ecliptic–Preces-
sion of the Equinoxes—Julian Calendar—Gregorian Cal-
endar, - - - - - *- - - -

CHA PTER VI.

Right Ascension and Declination—Sun Dials—Dialing—Di-

als and Clocks, - - - - - - - -

CHA PTE R W II.

Measurement of Time—Equation of Time–Longitude—

Quadrant—Method of determining apparent Time, - -

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