he same reason. The land begins to rise, and cast the warm shallow
seas from its face. The expansion of life has been more rapid and
remarkable than it had ever been before, in corresponding periods of
abundant food and easy conditions; the contraction comes more quickly
than it had ever done before. Mountain masses begin to rise in nearly
all parts of the world. The advance is slow and not continuous, but as
time goes on the Atlas, Alps, Pyrenees, Apennines, Caucasus, Himalaya,
Rocky Mountains, and Andes rise higher and higher. When the geologist
looks to-day for the floor of the Eocene ocean, which he recognises
by the shells of the Nummulites, he finds it 10,000 feet above the
sea-level in the Alps, 16,000 feet above the sea-level in the Himalaya,
and 20,000 feet above the sea-level in Thibet. One need not ask why the
regions of London and Paris fostered palms and magnolias and turtles in
Tertiary times, and shudder in their dreary winter to-day.

The Tertiary Era is divided by geologists into four periods: the
Eocene, Oligocene, Miocene, and Pliocene. "Cene" is our barbaric way of
expressing the Greek word for "new," and the classification is meant
to mark the increase of new (or modern and actual) types of life in
the course of the Tertiary Era. Many geologists, however, distrust
the classification, and are disposed to divide the Tertiary into two
periods. From our point of view, at least, it is advisable to do this.
The first and longer half of the Tertiary is the period in which the
temperature rises until Central Europe enjoys the climate of South
Africa; the second half is the period in which the land gradually
rises, and the temperature falls, until glaciers and sheets of ice cover
regions where the palm and fig had flourished.

The rise of the land had begun in the first half of the Tertiary, but
had been suspended. The Pyrenees and Apennines had begun to rise at
the end of the Eocene, straining the crust until it spluttered with
volcanoes, casting the nummulitic sea off large areas of Southern
Europe. The Nummulites become smaller and less abundant. There is also
some upheaval in North America, and a bridge of land begins to
connect the north and south, and permit an effective mingling of their
populations. But the advance is, as I said, suspended, and the Oligocene
period maintains the golden age. With the Miocene period the land
resumes its rise. A chill is felt along the American coast, showing a
fall in