Trains of Boulders, in Berkshire, Mass. 319 
shows that no such local lifting of the region has taken place. 
The entire absence of any evidence, in the position of the 
drift itself, of an alteration in the configuration of the surface 
since its deposition, produced either by secular or paroxysmal 
actions, is a sufficient demonstration that, whatever change of 
level may have oceurred, has been a general continental rising, 
as in the case of Sweden, shared alike by the valleys and 
mountains. The total absence of any undulations in the level 
of the marine clay beds of the river valleys, from the coast of 
Maine to the Hudson and St. Lawrence, is a conclusive proof 
that this uplifting has not been local, but general. 
But a more comprehensive refutation of this hypothesis of 
the origin of the drift from wandering icebergs, during an era 
9f general permanent submersion of the land, and compara- 
tively tranquil currents, is presented by the undeniable fact 
that the bed of every quiet sea must inevitably become the 
receptacle of fine-grained sediments, of some depth at least, 
entombing forms of animal and vegetable life, and which no 
subsequent denudation of its bed can altogether obliterate. 
But in connection with this great stratum of the drift, there is 
not to be discovered a solitary oceanic fossiliferous deposit to 
show that the land was then stationary below the level of the 
“a. That the drift-dispersing waters were above the land 
We do believe ; but their presence there was transient, in the 
Condition of a vast inundation, and while the level of the con- 
tinent was nearly what it is and has been since the appearance 
of the human race, 
According to another hypothesis, that which imputes the 
transport of boulders and erratics to the agency of glaciers, 
trains would be regarded as so many great moraines. 
But the well-known absence in the United States of lofty 
mountains penetrating the atmospheric level of perpetual snow, 
and acting as centres of dispersion for alpine glaciers, and the 
Proof afforded by the universal north and south direction of 
the strewn materials, and the furrows on their rocky floor, that 
RO such centres of dispersion existed, make the application, 
