Drift of the North German Lowland.—NSalishury. 295 
America, there are many questions connected with the formations 
of the ice age, concerning which there is not unity of opinion, 
and individual opinions are held, with certainly not less tenacity 
in Germany than in America. It is a conspicuous merit of the 
volume before us, that the author has stated with much fairness 
and discrimination the conclusions of other geologists where they 
do not agree with his own. In his copious bibliographical notes, 
the author shows his intimate familiarity with the literature of his 
subject. This is true not only of German literature, but of that 
of other countries as well. Although we are compelled to dis- 
sent from some of the conclusions reached by Dr. Wahnschatfe, 
and although we could have wished a fuller discussion of some of 
the questions involved, the volume is nevertheless a very satis- 
factory discussion of the glacial formations of the area under con- 
sideration. The order of treatment is generally historical, so that 
the volume gives us a sort of history of the evolution of opinion 
concerning the glacial formations of the territory described. 
The questions of glacial geology have been studied for the most 
part independently in Germany and in the United States. It is 
gratifying to observe how closely the conclusions arrived at by 
the geologists of the one country agree with those of the other. 
Yet there are some points of difference. In some cases these 
differences are hardly more than verbal, and yet these verbal 
ditferences have more than once given rise to misunderstandings 
and to controversy. In other cases the differences are radical. 
The differences in the Prepleistocene geology and topography of 
the ice-invaded territory of Germany and America may be largely 
responsible for the difference in the history of opinion in the two 
countries. The differences in the methods of work have likewise 
helped to develop diverse interpretations. It is interesting to 
note that the differences between the present conclusions of Ger- 
man and American glacialists are much less considerable than 
those of an earlier date, 
Topography and Relief of North Germany due mainly to Drift. 
Dr. Wahnschatte devotes a chapter to the discussion of the re- 
lations of the Prepleistocene formations of north Germany to the 
present surface. His conclusion, which seems to be well founded, 
is that the relief and topography of north Germany are mainly 
due to the disposition of the drift formations. A table of deep 
borings extending through the drift into the Prepleistocene forma- 
