146 THE GROWTH OF CONTINENTS. 
Silurian deposits, lying now between Finland and 
Russia, enlarged that region. 
The Silurian epoch has been referred by Elie 
de Beaumont to the system of upheaval called by 
him the system of Westmoreland and Hunds- 
riick, — again merely in reference to the spots at 
which these upheavals were first studied, the cen- 
tres, as it were, from which the investigations 
spread. But in their geological significance they 
indicate all the oscillations and disturbances of 
the soil throughout the region over which the 
Silurian deposits have been traced in Europe. 
The Devonian epoch added greatly to the out- 
lines of the Belgian island. To it belongs the 
region of the Ardennes, lying between France 
and Belgium, the Eifelgebirge, and a new dis- 
turbance of the Vosges, by which that region was 
also extended. The island of Bretagne was 
greatly increased by the Devonian deposits, and 
Bohemia gained in dimensions, while the central 
plateau of France remained much the same as 
before. The changes of the Devonian epoch are 
traced by Elie de Beaumont to a system of up- 
heavals called the Ballons of the Vosges and of 
Normandy, — so called from the rounded, bal- 
loon-like domes characteristic of the mountains 
of that time. To the Carboniferous epoch be- 
long the mountain-systems of Forcy, (to the west 
of Lyons,) of the North of England, and of tho 
