THE EARTH AS MODIFIED BY HUMAN ACTION.


CHAPTER 1.

INTRODUCTORY.

Natural Advantages of the Territory of the Roman Empire.--Physical Decay
of that Territory.--Causes of the Decay.--Reaction of Man on Nature.--
Observation of Nature.--Uncertainty of Our Historical Knowledge of
Ancient Climates.--Uncertainty of Modern Meteorology.--Stability of
Nature.--Formation of Bogs--Natural Conditions Favorable to Geographical
Change.--Destructiveness of Man--Human and Brute Action
Compared.--Limits of Human Power.--Importance of Physical Conservation
and Restoration--Uncertainty as to Effects of Human Action.

Natural Advantages of the Territory of the Roman Empire.

The Roman Empire, at the period of its greatest expansion, comprised the
regions of the earth most distinguished by a happy combination of
physical conditions. The provinces bordering on the principal and the
secondary basins of the Mediterranean enjoyed in healthfulness and
equability of climate, in fertility of soil, in variety of vegetable and
mineral products, and in natural facilities for the transportation and
distribution of exchangeable commodities, advantages which have not been
possessed in any equal degree by any territory of like extent in the Old
World or the New. The abundance of the land and of the waters adequately