ian Mountains" by M. Bertrand. The most western
range extended from Ireland through Wales and the south of England to
the central plateau of France; this was the "Armorican range" of E.
Suess. The eastern part of the chain passed from South France through
the Vosges, the Black Forest, Thuringia, Harz, the Fichtelgebirge,
Bohemia, the Sudetes, and possibly farther east; this constitutes the
"Varischen Alps" of Suess.

The sea had gained somewhat at the beginning of the Carboniferous
period in western Europe, but the effect of these movements, combined
with the rapid formation of detrital deposits from the rising land
areas, was to drive the sea steadily from the north towards the south,
until the open sea (with limestones) was relegated to what is now the
Mediterranean and to Russia and thence eastward. Similar events were
meanwhile happening in North America, for the seas were steadily
filled with sediments which drove them from the north-east towards the
south-west, and doubtless those movements which at the close of this
period uplifted the Appalachian mountains were already operative in
the same direction.

The folding of the Ural mountains began in the earlier part of this
period and was continued, after its close, into the Permian; and there
are traces of uplifts in central Asia and Armenia.

None of these movements appears to have affected the southern
hemisphere.

The net result of the erogenic movements was, that at the close of the
period there existed a great northern continental mass, embracing
Europe, North Asia and North America; and a great southern continental
mass, including South America, Africa, Australia and India. Between
these land masses lay a great Mediterranean sea--the "Tethys" of
Suess.

The conditions under which the beds of coal were formed will be found
described under that head; it will be sufficient to notice here that
some coal seams were undoubtedly formed by jungle or swamp-like
growths on the site of the deposit, and it is equally true that others
were formed by the transport and deposition of vegetable detritus. The
main point to observe in this connexion is that large tracts of land
in many parts of the world were at a critical level as regards the
sea, a condition highly favourable to frequent extensive incursions of
marine waters over the low-lying areas in a period of extreme crustal
instability.