TRANSACTIONS OF THE SECTIONS. 55 
pline. In my time, however, no other branches of learning were recognized than 
classics and mathematics, and I have with some shame to confess that I displayed 
but a “truant disposition” with respect to them, and too often hurried from the tutor’s 
lecture-room to the river or the field, to enable me to add much to the scanty stores 
of knowledge I had brought up with me. Had it not been, then, for the teaching 
of Professor Sedgwick in Geology, my time might have been altogether wasted, 
But it was not only in the lecture-room that I learnt from him. With that kind- 
ness of heart and geniality of disposition which make him as much loyed as his 
powers cause him to be admired, he was good enough to step down from his high 
place as a Professor of the University, and to take some notice of the young under- 
graduate whom he saw lingering over the trays of specimens when the lecture 
was over, to inquire his name, and to inyite him to his table. He subsequently 
allowed me to accompany him on some excursions in different parts of England, 
and gave me some of those practical lessons in the field, which, as you know, teach 
more in three days than can be learnt in months or yearsin the museum or the lecture- 
room. I look back upon these circumstances as those which gave direction to the 
whole course of my life, and as the origin of a paternal friendship with which Pro- 
fessor Sedgwick has honoured me for so many years, and which it has been my chief 
pride to endeavour to deserve. I hope, Ladies and Gentlemen, I may be pardoned 
for these few personal allusions; but amid all the gratification which I must ne- 
cessarily feel at the honour which has now fallen upon me, that, namely, of being 
called upon to preside, within the walls of my own Alma Mater, over the Geolo- 
gical Section of the British Association, it was impossible for me to neglect the 
opportunity of acknowledging the debt of gratitude I owe to one of the ruling 
spirits of both bodies, and of ayowing that my chief claim to occupy this chair 
is that Iam an old pak of Professor Sedgwick. 
One of the most obvious difficulties in the way of any person who now under- 
takes to preside over this Section is the thought of the contrast that will neces- 
sarily arise in the minds of many of you between him and his predecessors, That 
I am now occupying the seat that has been filled by Sedgwick, Buckland, Lyell, 
Murchison, Hopkins, De la Beche, Forbes, and so many other illustrious men, may 
well cause me to doubt my own capability of fulfilling its duties. One lesson I must 
certainly learn, and that is, to endeavour to make up for other deficiencies by atten- 
tion and assiduity, and, above all, not to take such an advantage of the postions 
as to bring anything of my own before your notice, to the hindrance of others 
who may have something to produce that may be more worthy of it. At the end, 
then, of this Address, which I will endeavour to make as brief as possible, I shall 
consider my own mouth as almost closed for the remainder of the meeting, and shall 
endeavour so far to imitate the Speaker of the House of Commons as to say as 
little as possible. 
I propose to take for my subject the external features of the earth’s surface. 
The principal business of Geology is to acquire as accurate a knowledge as we can 
of the internal structure of the crust of the earth, and to learn as much as possible 
of all the operations by which that structure was originally formed, or by which it 
has been subsequently modified. The crust of the earth has always been receiving 
accessions to its composition, both from within and from without. In like manner 
it has always been subject to modifying influences proceeding both from within and 
from without. It is obvious that the external influences act directly upon the 
actual surface of the time being. It is equally obvious that the internal influences 
can only reach that surface by penetrating through the thickness of the crust. 
If, therefore, we ask by what means the present surface of the earth, or, to bring 
the problem within more narrow limits, by what means the present surface of any 
of our dry lands, has been produced, we should naturally conclude that it owes its 
form to the external influences that have been brought to bear directly upon it, 
rather than to the indirect action of those deep-seated agencies, which can only 
reach it through an unknown thickness of solid rock. 
I believe this conclusion to be a true one. It is, however, by no means the idea 
which is commonly entertained, even by many geologists, while those who are not 
geologists are always inclined to refer all the more striking features of the surface 
