fty 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withdrawn."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 _Hydrogeologie_ closes with a "_Memoire sur la matiere du feu_" and
one "_sur la matiere 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.

[63] Quoted from Flourens' _Eloge Historique de Georges Cuvier_,
Hoefer's edition. Paris, 1854.

[64] _Remarques sur les Coquilles fossiles de quelques Cantons de la
Touraine_. Mem. Acad. Sc. Paris, 1720, pp. 400-417.

[65] _Eloge Historique de Werner_, p. 113.

[66] _History of Civilization_, i. p. 627.

[67] _France under Louis XV._, p. 359.

[68] _France under Louis XV._, p. 360.

[69] See vol. iii. of his _Memoires sur differentes Parties des Sciences
et des Arts_, pp. 209-403. Geikie does not give the date of the third
volume of his work, but it was apparently about 1771, as vol. ii. was
published in 1770. I copy Geikie's account of Guettard's observations
often in his own words.

[70] Lyell's _Principles of Geology_.

[71] Geikie states that the doctrine of the origin of valleys by the
erosive action of the streams which flow through them, though it has
been credited to various writers, was first clearly taught from actual
concrete examples by Desmarest. _L. c._, p. 65.

[72] Jameson's _Cuvier's Theory of the Earth_, New York, 1818.

[73] J. G. Lehmann of