xploration) the bed of
the whole Atlantic Ocean is now mapped out, with the result that an
immense bank or ridge of great elevation is shewn to exist in
mid-Atlantic. This ridge stretches in a south-westerly direction from
about fifty degrees north towards the coast of South America, then in
a south-easterly direction towards the coast of Africa, changing its
direction again about Ascension Island, and running due south to
Tristan d'Acunha. The ridge rises almost sheer about 9,000 feet from
the ocean depths around it, while the Azores, St. Paul, Ascension, and
Tristan d'Acunha are the peaks of this land which still remain above
water. A line of 3,500 fathoms, or say, 21,000 feet, is required to
sound the deepest parts of the Atlantic, but the higher parts of the
ridge are only a hundred to a few hundred fathoms beneath the sea.

The soundings too showed that the ridge is covered with volcanic
_debris_ of which traces are to be found right across the ocean to the
American coasts. Indeed the fact that the ocean bed, particularly
about the Azores, has been the scene of volcanic disturbance on a
gigantic scale, and that within a quite measurable period of geologic
time, is conclusively proved by the investigations made during the
above named expeditions.

Mr. Starkie Gardner is of opinion that in the Eocene times the British
Islands formed part of a larger island or continent stretching into
the Atlantic, and "that a great tract of land formerly existed where
the sea now is, and that Cornwall, the Scilly and Channel Islands,
Ireland and Brittany are the remains of its highest summits" (_Pop.
Sc. Review_, July, 1878).

_Second._--The proved existence on continents separated by great
oceans of similar or identical species of fauna and flora is the
standing puzzle to biologists and botanists alike. But if a link
between these continents once existed allowing for the natural
migration of such animals and plants, the puzzle is solved. Now the
fossil remains of the camel are found in India, Africa, South America
and Kansas: but it is one of the generally accepted hypotheses of
naturalists that every species of animal and plant originated in but
one part of the globe, from which centre it gradually overran the
other portions. How then can the facts of such fossil remains be
accounted for without the existence of land communication in some
remote age? Recent discoveries in the fossil beds of Nebraska seem
also to prove that the