as on the adjacent coast of Europe. We are therefore compelled
to assume, that at that time the English Channel and the Irish
Sea were not in existence. This necessitates an elevation of at
least four hundred feet, which would also lay bare a large
portion of the North Sea.<5> In proof of this latter statement
is the fact, that, at a distance from land in the North Sea,
fishermen at the present day frequently dredge up bones and
teeth of animals that then roamed in Europe.<6>


Map of Europe------------------


While there is no necessity for supposing an elevation greater
than that required to lay bare a passage for animals back and
forth, yet soundings undertaken by the British government have
established the fact, that the ocean deepens very gradually away
from the shores of the main-land until a depth of six hundred
feet is reached, when the shore falls away very suddenly.
This is supposed to be the sea-coast of that time. The English
Channel would then have existed as the valley of the Seine, and
the Rhine have prolonged its flow over the present bed of the
North Sea. As the land stood at this height through a large
portion of the Glacial Age, it is not at all unreasonable to
suppose that primitive tribes hunted back and forth along these
valleys, and so doubtless many convincing proofs of their
presence at that early day lie buried underneath the waves of
the sea. In like manner, at the south, we know that elephants,
lions, and hyenas passed freely from Africa to Spain, Italy, and
the Island of Crete,<7> and, consequently, the Mediterranean Sea