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structure and motion of the inland-iee in Greenland. According to 
the earlier ideas the bottom-moraine was pushed forward under 
the ice, from the centrum of dispersion of the latter; to day we 
know that stones, sand and mud are transported included strata-like 
in the inferior parts of the ice mass, by the gradually melting of which 
the bottom-moraine is formed. Further it is known, that the motion 
of the inferior strata of an inland-ice mass becomes the slighter 
the more these are laden with stones and mud. Evidently this load 
was less above the strip of land which actually constitutes the eastern, 
most elevated portion of the Hondsrug than at the west of this portion, 
where the ice in its downmost parts must have been thickly laden 
with clay. Above this strip we may suppose to have existed a 
relatively more rapid motion of the inland-ice in comparison with 
above the extensive western clay banks, the result of which difference 
would have been a lower level of the ice in the first and a higher 
in the latter parts. Thus, actually, in Greenland a considerable diminish- 
ing of the motion and a swelling of the ice is seen there where in 
its undermost strata it is strongly laden with debris of rock, and 
lowering of the surface where this motion is not hindered, on account ot 
the lowest ice-strata being relatively pure. Thence considerable pressure 
on the underground where those clay banks are now to be found 
in the Hondsrug and a minimum of pressure near the eastern border; 
there then the loose Rhine-sand, drenched with water was as a whole 
mass uplifted. 
The situation of the elevated ridge of preglacial sand side by side 
with the long and broad western strip of boulder-clay makes us also 
suppose that the direction in which the ice moved was not, as is still 
generally admitted, from north-east to south-west or from north to south, 
but the same as the extension of the Hondsrug, from north-west to 
south-east. Now with this supposition perfectly agrees the at first 
sight paradoxical direction of motion as derived from the shifted 
boulder of quartzite. 
But how then can we account for the fact that the boulder-clay 
was laid down principally in a long and broad strip along the western 
part, whilst the boulder-sand above it is uniformly thick with that 
in the eastern part on the Hondsrug where clay is generally absent 
under it? This question too is not difficult to solve with our 
actual knowledge of the phenomena of the motion of an inland-ice 
mass. The material of the boulder-sand bed may have been trans- 
ported as a continuous bed by higher ice-strata, at the same time as 
disjuncted strips and patches of clay were included in the lower 
ice-strata, or the sand with its boulders may have been transported 
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