60 Clement Reid—Glacial Deposits of Cromer. 
within a few inches of the smooth undisturbed surface of the Pre- 
glacial beds. 
If we consider the generally accepted theory that the contortions 
were formed by floating-ice, it is evident that an iceberg ploughing 
up the sea-bottom must necessarily most disturb the highest beds, 
and the disturbance would die out gradually below and not end 
abruptly. To plane off such an even surface of the Pre-glacial beds 
the icebergs must be flat-bottomed and all submerged to the same 
extent. The ice must move quite steadily, not rocking, and must be 
of great thickness, or else it would at once pack. 
In no part of the world can we point to floating-ice capable of 
forming disturbances equal to those seen at Trimmingham, and it 
should not be forgotten that there is no evidence at that period of a 
submergence sufficient to float thick ice, or of an open sea in which 
it could obtain the necessary momentum. The iceberg theory must 
therefore be abandoned. 
What other explanation is then possible? Dr. Croll, in his “Climate 
and Time,” has pointed out that at the period of maximum glaciation, 
that is to say, at the time of the Chalky Boulder-clay, the North Sea 
was entirely filled with ice, which flowed from a north-easterly 
direction over Norfolk. Before reading either Dr. Croll’s or Dr. 
James Geikie’s books, I thought it advisable to examine the coast, 
so as to form a quite independent judgment, and on comparing my 
observations lately with Dr. Croll’s previously published views, I 
was greatly surprised at the close coincidence. 
If the contortions are carefully examined, they clearly show that 
they were formed by a lateral thrust from N.E. or N.N.E., which on 
other grounds Dr. Croll gives as the direction of the flow. 
But how can we account for the detached masses of chalk at the 
base of the contorted beds ? 
For many years the singular isolated character of the bluffs of 
chalk at Trimmingham has been accounted for on the various 
suppositions, that they formed islands in the Pliocene or Boulder- 
clay sea, or else of some Post-glacial disturbance, or lastly the 
Rev. O. Fisher,' among other explanations, suggests that “in 
attributing contortions in the underlying beds to the deposition of 
masses of matter upon their surface, 1 would go to the extent of 
suggesting that the remarkable bluffs of chalk at Trimmingham may 
have been upraised by some such action.” 
It has long been known that the lines of flint have been to a 
great extent affected by the disturbance, and two years ago, in 
measuring the westerly chalk mass, I discovered that they weree 
folded into a complete loop, and also, as previously noted by 
Mr. Fisher, that the same beds were to be seen in the cliff and on 
the foreshore directly opposite. Fortunately a projecting point of 
the cliff enabled me to draw sections at right angles as well as ina 
line with the coast, and I saw that the direct action of an ice-sheet - 
was the only way in which we could account for the extraordinary 
disturbance of the beds. 
 Guox. Mac, 1868, Vol. V. p. 550, 
