GLACIAL DRIFT. 315 
An example more nearly analogous to our own is afforded by the former 
extension of the Scandinavian glaciers. Erdmann’s map represents striae 
pushing northerly into the Arctic ocean ; south-easterly, in the promon- 
tory between the gulfs of Finland and Bothnia; south-east and south, 
varying west of south, also, in the lower part of Sweden; west, north- 
west, and south-west, in Norway towards the Atlantic ocean. Croll sup- 
plements this map, by showing the continuation of the southerly course 
into Prussia; a bending of the direction to conform with the Baltic sea, 
passing over Denmark to both the south and north of England. Scot- 
land and England are made to send off additional ice-currents; and the 
western edge of the ice-sheet reaches to west longitude 14°, or as far as 
the seaward limit of comparatively shallow water. This area is certainly 
1,700 miles wide, and 1,500 from north to south. This will compare 
favorably in size with our American glaciated area. The latest author- 
ities show that the phenomena are all explicable by the existence of a 
principal central ridge of dispersion in Scandinavia and subordinate ones 
in Great Britain; also, that there is no evidence of the flow of ice from 
the polar regions into northern Europe. There exists, therefore, a close 
analogy between the glacial conditions of Scandinavia and North Amer- 
ica ;—and if the former can be explained upon the theory of a centre of 
dispersion, so can the latter. 
Before considering the location of the American centre of dispersion, 
it will be well to recall the glacial conditions existing at the present time 
in Greenland, since they will illustrate the state of things in New Eng- 
land during the period of the greatest cold. We discover there how the 
ice can move up hill, and how the ground moraine can be formed. 
GLACIERS IN GREENLAND. 
Greenland was discovered by Gunnibiorn in 872, In 983, Eric the 
Red, banished from Iceland, established a colony near the south end of 
Greenland, imposing upon it the name it now bears. The settlement 
prospered; and indications of civilization left behind by these Norsemen 
exist as far north as Upernavik (latitude 72° 50’), or as far north as the 
stoutest ships of modern times can sail without encountering serious 
risk, The population increased sufficiently to require the services of a 
bishop; and a list of seventeen of them, from 1126 to 1406, has been 
