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DR. BUCKLAND and the GLACTAL THEORY. 
Switzerland some deposits must have crossed Lake Geneva, and 
ascended very high mountains. Does Profossor Agassiz suppose that 
the Lake of Geneva was occupied by a glacier 3,000 feet thick? 
(Agassiz. —“ At least! ”) [Mr. Greenough then referred to the] 
Changes of climate necessary to account for these phenomena [and to 
the] objection from the tropical nature of remains in recent deposits. 
[He considered it to be the] climax of absurdity in geological opinions. 
In one period, the Crag, we have three opposite conditions blended: 
Corals, Tropical; Peat, Temperate ; Shells, pronounced by Dr. Beck, 
Arctic! 
Mr. Lyell. —Mr. Greenough confuses four distinct epochs under 
the name of Crag. The first comparatively tropical (Coralline Crag), 
the others temperate (Bed and Norwich Crag), and the period of the 
peat bogs (Lacustrine deposits) more recent than any. 
Mr. John Edward Gray. —The corals of the Crag appear to 
me as Arctic as the shells. I know no reason for making them 
tropical. 
Mr. Greenough [remarked] on the size of the blocks on mountains, 
the agency of floating ice, and on mountains as the physical boundaries 
of different kinds of diluvium. 
Dr. Mitchell enquired if Dr. Buckland confined the glaciers to the 
Highlands or whether he made them descend to the Lowlands. 
Dr. Buckland expressed himself ready to answer any question on 
the subject under discussion, or any involved in his paper, but con¬ 
sidered the present question irrelevant. 
Dr. Mitchell considered his question relevant to the subject. 
Dr. Buckland rose to reply, but Mr. Whbwell rose (cheers and 
“Mr. Whewell!”) 
Mr. Whewell. —At this late hour it is impossible to go into the ques¬ 
tion of the physical changes necessary to allow of the existence of glaciers 
in this country. I shall, therefore, confine my remarks to the subject 
as discussed this evening, and it does appear to me that the way in 
which Mr. Lyell has treated it is not the most fair and legitimate. 
He says, “If we do not allow the action of glaciers, how shall we 
account for these appearances ? ” This is not the way in which we 
should be called upon to receive a theory. Now it is not within our 
reach at present to refer each set of phenomena in geology to its 
adequate cause, but that is no reason why we should receive any 
theory that is offered to account for it. This glacial theory is brought 
forward to explain what has hitherto, to a great extent, been found 
inexplicable — the nature and position of diluvial detritus over 
considerable areas and in widely different climates. So far as it is 
founded on strict comparison and analogy, it is to be received; 
but we must not overrate its influence; and it appears to me 
incomplete in three important particulars :— Firstly, in accounting for 
such an extent of diluvium over such wide areas, in countries of such 
