Passing by his speculations on the displacement of the poles of the earth, and on the elevations of the equatorial regions, which will dispense with the necessity of considering the earth as originally in a liquid condition, he allows that “the terrestrial globe is not at all a body entirely and truly solid, but that it is a combination (réunion) of bodies more or less solid, displaceable in their mass or in their separate parts, and among which there is a great number which undergo continual changes in condition.”
It was, of course, too early in the history of geology for Lamarck to seize hold of the fact, now so well known, that the highest mountain ranges, as the Alps, Pyrenees, the Caucasus, Atlas ranges, and the Mountains of the Moon (he does not mention the Himalayas) are the youngest, and that the lowest mountains, especially those in the more northern parts of the continents, are but the roots or remains of what were originally lofty mountain ranges. His idea, on the contrary, was, that the high mountain chains above mentioned were the remains of ancient equatorial elevations, which the fresh waters, for an enormous multitude of ages, were in the process of progressively eroding and wearing down.
What he says of the formation of coal is noteworthy:
“Wherever there are masses of fossil wood buried in the earth, the enormous subterranean beds of coal that are met with in different countries, these are the witnesses of ancient encroachments of the sea, over a country covered with forests; it has overturned them, buried them in deposits of clay, and then after a time has withdrawn.”
In the appendix he briefly rehearses the laws of evolution as stated in his opening lecture of his course given in the year IX. (1801), and which would be the subject of his projected work, Biologie, the third and last part of the Terrestrial Physics, a work which was not published, but which was probably comprised in his Philosophie zoologique.
The Hydrogéologie closes with a “Mémoire sur la matière du feu” and one “sur la matière du son,” both being reprinted from the Journal de Physique.
FOOTNOTES:
[60] Evolution in Biology, in Darwiniana, New York, 1896, p. 212.
[61] Principles of Geology.
[62] Lyell’s Principles of Geology, 8th edit., p. 22.