441 
These marks are no way dependant on the strike of the 
beds, being in some cases oblique, in others directly across 
the strike of the beds in their level line, or a line at right 
angles to their greatest declivity or dip. 
It is sometimes necessary to apply the touch as well as 
sight to distinguish the scratches, for in slate rocks the joints 
of cleavage present an appearance exactly similar to the 
scratches ; one, however, to the touch is perfectly smooth, 
while the scratches or indentations may be very perceptibly 
felt. 
In judging of hand specimens, it is difficult to distinguish 
the groovings, or flutings and scratches, from similar marks, 
which may be caused in a variety of ways. Observers must, 
therefore, be on their guard, for it is only when viewed in 
situ and upon a large scale, that these characteristics are to 
be relied upon. 
The phenomena of large masses of drift have never been 
investigated minutely, and the introduction of glacial action 
as an important agent in their production and dispersion, is 
calculated to throw much light on the subject, by affording 
an agency of which clear records have been preserved, if the 
forms and groovings which have been described are rightly 
attributed to former glaciers. 
Those who will pursue this subject by reading the work of 
Agassiz, or the details of further observations made by 
English geologists as inserted in the Transactions of the 
Geological Society, will find that mucb more might be 
said in relation to moraines. My object, however, has not 
been so much to enter on a description of all the phenomena, 
as to present the more prominent features. The litho- 
graphed drawings of Agassiz furnish to the observer, at 
a single glance, a clear idea of the undoubted evidence 
afforded by the rocks in Switzerland. I have drawings which 
exhibit the like forms as observed in various parts of this 
