Outlines of the Earth's History: A Popular Study in Physiography
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Nathaniel Southgate Shaler. Outlines of the Earth's History: A Popular Study in Physiography
Outlines of the Earth's History: A Popular Study in Physiography
Table of Contents
PREFACE
LIST OF FULL-PAGE ILLUSTRATIONS
CHAPTER I. an introduction to the study of nature
CHAPTER II. ways and means of studying nature
CHAPTER III. the stellar realm
Motions of the Spheres
The Solar System
The Constitution of the Sun
CHAPTER IV. the earth
CHAPTER V. the atmosphere
Whirling Storms
The System of Waters
The Ocean Currents
The Circuit of the Rain
Geological Work of Water
Lakes
CHAPTER VI. glaciers
CHAPTER VII. the work of underground water
Volcanoes
CHAPTER VIII. the soil
CHAPTER IX. the rocks and their order
Earthquakes
Duration of Geological Time
The Moon
Methods in studying Geology
INDEX
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Nathaniel Southgate Shaler
Published by Good Press, 2019
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It is characteristic of chemical science that it takes account of actions which are almost entirely invisible. No contrivances have been or are likely to be invented which will show the observer what takes place when the atoms of any substance depart from their previous combination and enter on new arrangements. We only know that under certain conditions the old atomic associations break up, and new ones are formed. But though the processes are hidden, the results are manifest in the changes which are brought about upon the masses of material which are subjected to the altering conditions. Gradually the chemists of our day are learning to build up in their laboratories more and more complicated compounds; already they have succeeded in producing many of the materials which of old could only be obtained by extracting them from plants. Thus a number of the perfumes of flowers, and many of the dye-stuffs which a century ago were extracted from vegetables, and were then supposed to be only obtainable in that way, are now readily manufactured. In time it seems likely that important articles of food, for which we now depend upon the seeds of plants, may be directly built up from the mineral kingdom. Thus the result of chemical inquiry has been not only to show us much of the vast realm of actions which go on in the earth, but to give us control of many of these movements so that we may turn them to the needs of man.
Animals and plants were at an early day very naturally the subjects of inquiry. The ancients perceived that there were differences of kind among these creatures, and even in Aristotle's time the sciences of zoölogy and botany had attained the point where there were considerable treatises on those subjects. It was not, however, until a little more than a century ago that men began accurately to describe and classify these species of the organic world. Since the time of Linnæus the growth of our knowledge has gone forward with amazing swiftness. Within a century we have come to know perhaps a hundred times as much concerning these creatures as was learned in all the earlier ages. This knowledge is divisible into two main branches: in one the inquirers have taken account of the different species, genera, families, orders, and classes of living forms with such effect that they have shown the existence at the present time of many hundred thousand distinct species, the vast assemblage being arranged in a classification which shows something as to the relationship which the forms bear to each other, and furthermore that the kinds now living have not been long in existence, but that at each stage in the history of the earth another assemblage of species peopled the waters and the lands.
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