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distribution of the science of geology according to which T arranged 
my remarks in the Address which I had last year the honour of 
reading to the Society; I mean the primary division into Deserip- 
tive Geology and Geological Dynamics; the former implying a de- 
scription of the rocks of the earth’s surface according to an esta- 
blished classification of strata and formations; and the latter dealing 
with the study of those general Jaws and causes of change by which 
we hope to understand and account for the facts which Descrip- 
tive Geology brings before us ;—in short, the present condition and 
the past history of the earth’s crust. But as the laws of permanence 
and change, with regard to organized beings, differ very widely from 
the dynamics of brute matter, we may conveniently make a separate 
study of the relations of organic life to which geology conducts us, 
and may mark it by the name Palaontology, by which it is com- 
monly known. I will add that it still appears to me convenient, for 
the present, to divide Descriptive Geology into two portions,—the 
Home circuit, in which the order of superposition has already been 
established with great continuity and detail ; and the Foreign region, 
in which we are only just beginning to trace such an order. [I shall 
also, as before, take the ascending order of strata. According to 
this arrangement of the science, I shall venture to bring to your re- 
collection a few of the points to which our attention has mainly been 
called during the past year. 
DESCRIPTIVE GEOLOGY. 
1. Home (North European) Geology.—When I stated that De- 
scriptive Geology has for its task the reference of the rocks of some 
portion of the earth’s surface to an established classification into 
strata and formations, it was implied, that the more common employ- 
ment of the descriptive geologist must be to refer the rocks which 
he examines to some classes already fixed and recognized ; but it 
could hardly fail to occur to you, that from time to time the leaders 
in this study will be called upon to execute a more weighty and ele- 
vated office, in framing the classifications which other observers are 
to apply ; in drawing the great lines of division and subdivision which 
fix the form of the subject; in setting up the type with which ex- 
amples are to be compared ; in constructing the language in which 
