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POSITIONS OF ANCIENT CONTINENTS 
In its general form, its northeast extension across the northern 
Atlantic and its eastward extension into the Atlantic, this early 
Cambric continent fully agrees with the Pre-Cambrian continent 
inferred by us from the trend lines of the Pre-Cambrian folding 
and foliation. It was therefore already in Cambric time a conti¬ 
nental mass of long existence; dating back even into Archeozoic 
time, according to the evidence from the Archean folds. 
As a perusal of Ulrich’s and Schuchert’s authoritative charts 
will readily show, this continent has, in its main body, persisted 
through all later time as a distinct entity. It has been invaded by 
epicontinental seas from various directions, principally the four 
cardinal directions, but has frequently again emerged. The one 
great exception is the large continental extension to northern 
Europe across the north Atlantic. This mass of continental size 
existed as an undoubted land-mass until Devonic time, where as the 
“Eria” of some paleogeographers, and the “Atlantis” of others, it 
comprised even the greater part of Great Britain, Scandinavia, and 
northern Russia. The Atlantic was then restricted to the “Posei¬ 
don” of Schuchert, whose northern boundary extended straight 
across from Labrador to middle Ireland. In more restricted form 
Eria can still be traced until Triassic time. As Holtedahl points 
out, this part of the crust had through long geologic periods the 
tendency to rise; but like the eastern part of Appalachia it has now 
sunken deeply. Suess, clearly recognizing the connection of the 
Armorican folds in the Bretagne with the Appalachian folds in 
America — with their northeast bend in Gaspe and Newfoundland 
— drew the northern shore-line of the Poseidon along this sunken 
Devonic mountain range and derived the northern Atlantic Ocean 
from the breaking down of the Paleozoic continental mass of 
“Atlantis.” 
We see in the great unconformities of the Pre-Cambrian of 
North America and Eurasia strong evidence that the supposed con¬ 
tinental areas responded as continental units not only to the orogenic 
forces that folded them, but also to the epeirogenic forces that ele¬ 
vated them from time to time. While the continents, according to 
the recent investigations of isostasy, are composed of positive and 
negative elements that, owing to minor diflferences in relative 
density, act more or less independently, they seem nevertheless to 
have formed units of a major grade that reached uniformly in 
