- EAN13
- 9782386260193
- Éditeur
- EHS
- Date de publication
- 19/02/2024
- Langue
- anglais
- Fiches UNIMARC
- S'identifier
Livre numérique
-
-
Aide EAN13 : 9782386260193
- Fichier EPUB, avec Marquage en filigrane
2.99
We are all familiar with the general conclusion arrived at by geologists that
our earth has experienced many climatic changes. There have been times when
genial conditions ranged up to the highest latitudes, and times also when the
cold of the arctic regions descended to what is now our temperate zone. The
cause or causes of those remarkable vicissitudes still baffle research. Many
explanations have been advanced, some highly improbable, others perhaps more
likely, while of yet others it may be said that possibly they contain a
certain amount of truth. But no one theory or hypothesis has succeeded in
gaining general assent, and we shall not therefore at present concern
ourselves with any. In place of reviewing hypotheses and speculations, I shall
limit myself to a survey of certain facts connected with the later geological
history of our continent, the meaning of which is more or less apparent. The
evidence referred to leads to the conclusion that Middle Europe has within the
human period experienced conditions such, as now obtain in the tundras and
barren grounds of circumpolar regions. When these conditions passed away, the
central and west-central areas of our continent became steppe lands,
comparable as regards climate to the subarctic steppes of southeast Russia and
southwest Siberia.
As geologists reason from the present to the past, it will be well to take
first a brief glance at those regions of the globe where at present tundra and
steppe conditions respectively prevail. When we have realized the salient
characters of those regions, and the nature of their floras and faunas, we
shall be in a better position to understand the bearing of the geological
evidence.
ABOUT THE AUTHOR
James Geikie (1839–1915) was a Scottish geologist and younger brother of Sir
Archibald Geikie. He also made significant contributions to the field of
geology.
our earth has experienced many climatic changes. There have been times when
genial conditions ranged up to the highest latitudes, and times also when the
cold of the arctic regions descended to what is now our temperate zone. The
cause or causes of those remarkable vicissitudes still baffle research. Many
explanations have been advanced, some highly improbable, others perhaps more
likely, while of yet others it may be said that possibly they contain a
certain amount of truth. But no one theory or hypothesis has succeeded in
gaining general assent, and we shall not therefore at present concern
ourselves with any. In place of reviewing hypotheses and speculations, I shall
limit myself to a survey of certain facts connected with the later geological
history of our continent, the meaning of which is more or less apparent. The
evidence referred to leads to the conclusion that Middle Europe has within the
human period experienced conditions such, as now obtain in the tundras and
barren grounds of circumpolar regions. When these conditions passed away, the
central and west-central areas of our continent became steppe lands,
comparable as regards climate to the subarctic steppes of southeast Russia and
southwest Siberia.
As geologists reason from the present to the past, it will be well to take
first a brief glance at those regions of the globe where at present tundra and
steppe conditions respectively prevail. When we have realized the salient
characters of those regions, and the nature of their floras and faunas, we
shall be in a better position to understand the bearing of the geological
evidence.
ABOUT THE AUTHOR
James Geikie (1839–1915) was a Scottish geologist and younger brother of Sir
Archibald Geikie. He also made significant contributions to the field of
geology.
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