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borough and Bacton Gap (about three miles) consist generally of 
the lignite or forest bed at the bottom, overlaid by till containing 
boulders of granite, quartz and fragments of Norwich crag shells; 
then in ascending order, laminated blue clay ; and at the top strati- 
fied yellow sand; the entire height being from thirty to forty feet. 
Between Bacton Gap and Mundesley the cliffs are higher, and con- 
sist of drift with boulders; and they exhibit the first fine exemplifi- 
cations of contortions, and of folded or contorted beds resting upon 
others which appear to have undergone no disturbance. From 
Mundesley to Trimmingham, the cliffs in the lower part are com- 
posed of till containing fragments of white chalk, and the upper of 
stratified drift. Whether the lignite bed is interposed between the 
chalk and the drift all the way, Mr. Lyell could not ascertain; but 
he found about a mile north-west of Mundesley, at the bottom of the 
cliff, a substratum inclosing numerous flattened leaves and branches. 
To the north-west of Cromer, the drift cludes a much larger quan- 
tity of chalk rubble than to the southward. 
Disturbance of the strata. Yn no portion of Great Britain, Mr. 
Lyell observes, are there evidences of more complicated disturbances 
of a modern date than in the mud-cliffs of Norfolk, or disturbances 
more difficult to explain. In many parts of the cliffs the beds are 
twisted and contorted into every possible curvature, and the replica- 
tions are in some instances so numerous, that a bed may be inter- 
sected three times in the same vertical well or boring. Occasionally 
the beds are vertical ; sometimes they present concentric crusts enve- 
loping a nucleus of sand, gravel or chalk, occasionally more than 
twenty feet in diameter. One instance, mentioned by Mr. Lyell, con- 
sists of a nucleus of blue clay successively surrounded by layers of 
white sand, yellow sand, striped loam and clay, laminated blue clay : 
and in another case he counted thirty distinct strata enveloping a nu- 
cleus of sand. These strange bendings, twistings and other irregu- 
larities are not continuous, though characteristic of the greater por- 
tion of the cliffs, but are in some cases limited to a small area, both 
in vertical height and lateral extension. Occasionally they range 
from the top to the bottom of the cliff; but not unfrequently beds 
thus disturbed rest upon others perfectly horizontal. 
To account for these phenomena, Mr. Lyell says, is extremely 
difficult, and he prefers leaving their final elucidation to the assist- 
ance which future sections may afford to offering any positive ex- 
planation. The nuclei, he is of opinion, are only the inner portions of 
a series of strata bent into a convex form, as the removal of portions 
of the cliff gradually develop other layers within those which 
had formed previously an apparent nucleus. When the disturbed 
beds are in the immediate vicinity of protuberances of chalk, he is in- 
clined to think that the greater resistance offered by the hard masses 
of chalk at the time the country was raised above the level of the sea 
might have produced a disturbance in the yielding strata of drift ; but 
he thinks that this explanation will not account for all the phenomena 
presented in the neighbourhood of the chalk pinnacle at Old Hythe 
Point, near Sherringham. Where the disturbed strata are associated 
