ces, especially iron, copper, lead, and tin, exist in great
abundance, and have been worked from the earliest ages. Potter's clay
and salt also exist, the former furnishing the basis of industry for
an extensive section of the midlands. By far the most important
mineral possession of England, however, is her coal. This exists in
the greatest abundance and in a number of sections of the north and
west of the country. Practically unknown in the Middle Ages, and only
slightly utilized in early modern times, within the eighteenth and
nineteenth centuries her coal supply has come to be the principal
foundation of England's great manufacturing and commercial
development.

The lowlands, which make up far the larger part of the country, are
covered with soil which furnishes rich farming areas, though in many
places this soil is a heavy and impervious clay, expensive to drain
and cultivate. The hard ridges are covered with thin soil only. Many
of them therefore remained for a long time covered with forest, and
they are devoted even yet to grazing or to occasional cultivation
only.

The abundance of harbors and rivers, navigable at least to the small
vessels of the Middle Ages, has made a seafaring life natural to a
large number of the people, and commercial intercourse comparatively
easy with all parts of the country bordering on the coast or on these
rivers.

Thus, to sum up these geographical characteristics, the insular
situation of England, her location on the earth's surface, and the
variety of her material endowments gave her a tolerably well-balanced
if somewhat backward economic position during the Middle Ages, and
have enabled her since the fifteenth century to pass through a
continuous and rapid development, until she has obtained within the
nineteenth century, for the time at least, a distinct economic
precedency among the nations of the world.

*2. Prehistoric Britain.*--The materials from which to construct a
knowledge of the history of mankind before the time of written records
are few and unsatisfactory. They consist for the most part of the
remains of dwelling-places, fortifications, and roadways; of weapons,
implements, and ornaments lost or abandoned at the time; of burial
places and their contents; and of such physical characteristics of
later populations as have survived from an early period. Centuries of
human habitation of Britain passed away, leaving only such scanty
remains and the obscure and dou