rivers and the rocks, the seas and the continents have been changed
in all their parts; but the laws which direct those changes, and
the rules to which they are subject, have remained invariably the
same." -From Charles Lyell's, The Principles of Geology,
geologic theory, made famous by Charles Lyell in the 1830's
in his journal called The Principles of Geology, was based
on the premise that all things have changed, and will continue to
change, and all things have done so and will do so under the same
forces of nature. He conjectures that for millions of years, earthquakes,
floods, volcanoes and the movement of the plates have caused the
destruction and the formation of new mountains and land structures.
This theory allowed the geologists to look at mountains for their
rock structure, and relate different mountain ranges with one another,
thus conjecturing about their ages. Lyell attempted to date the
Alps, yet they never were able to ascertain the number of "different
periods at which the Alps gained accessions to the height and width"
(Lyell, 137). They were however able, because of modern theory,
to derive the last series of movement, which he believed "occurred
when seas were inhabited by many existing species of animals"
discovered that glacial movements in these mountains have torn
fissures, and continue to tear fissures, in the sides of mountains.
"When valleys have become filled with ice, the contraction
of the mass causes innumerable deep rents, such as are seen in the
mer de glace on Mont Blanc..." (Lyell, 98). Like this lithograph
of the Mer de Glace, near Mont Blanc, circa 1860, the fissures and
broken rocks are seen, as well as the glacial ice cutting far back
into the mountain.