188 LIFE OF
water from the other creative processes of the planet,
and ingeniously connects the geographic knowledge of
the earth with geology. He considers the present
form of the continent as an elevation above the level
of the sea, produced principally by the . eruption of
quartz porphyry, which has broken through the pri-
meval terrestrial vegetation, as shown in the present
coal deposits. What we call lowlands, Humboldt de-
scribes as broad ridges of hills and mountains, whose
bases lie at the bottom of the sea—a table land, in
short. The horizontal form of the land of the planet,
—which is as 1 to 2-f- to the quantity of water, and
of which there is three times more on the northern
than on the southern oceanic hemisphere—has occu-
pied Humboldt's investigating mind, the more as
even In the times of Grecian antiquity it had excited
great interest. The direction which the longitude
measurement of the old and new world takes, has led
Humboldt to new researches. Our old continent has
its greatest length from east to west, while America
lias hers from north to south; and while, in the north,
these two continents are abruptly cut off at their
greatest breadth, they terminate in the south in pyra-
midical points, which Humboldt thinks the more
characteristic because this southern pointed formula
repeated on all the smaller quarters and peninsulas ;
and it has been proved that, the more simple the
coast form and the divisions of a continent appear,
the more uniform, has remained the education and
civilization of the inhabitants. He compares the
much divided Europe to the uniform. Asia, Africa,
and South America. He acknowledges a subterranean
power as the operating cause of all continental forma-
tion which did not create the entire continent at once
and simultaneously, but at different epochs, by exten-
sion and elasticity of hot vapours and exhalations,
which have, at different times, raised the earth's sur-
face over the water, and by SLibsequent earthquakes
aad eruptions, formed the details of hill and valley.
This elevation and revolution of the continent, Hum-