19 
line of coast. A little more to the north, this heap of rock ruins is suc- 
ceeded by a group of vertical strata, which are evidently the base and side 
of an anticlinal ridge, for still more to the north we can trace the three 
bands of slate, which are here perpendicular, sloping down from the top 
of the cliff to the bottom where they are lost to sight as they plunge under 
the beach. The axis of this anticlinal is so clearly and sharply denned 
that I consider it about the most instructive section of the kind known. 
The folding of the strata is so abruj)t that in the axis or centre of the fold 
they are fractured or split in a direct line from the top of the cliff to its 
base. The height of the vertical strata is, if I recollect rightly, one hun- 
dred and eleven feet. Unfortunately the measured section of the whole 
line of coast has been lost. It is worthy of remark that in the centre of 
every fold a grey coloured nucleus is seen. The material of this 
nucleus is now hard but it is probable that when the rocks were bent 
and folded it was more plastic and yielding than the associated strata that 
envelope it. 
By attending to the position of the three beds of splintery slates we find 
them alternately appearing and disappearing in repeated folds, and can 
thus trace them along the cliffs where they sometimes dip under the beach 
and^at no great distance emerge from it until they finally disappear in the 
low cliff on the border of Duncannon strand. In this section we have a 
succession of anticlinals and synclinals extending along a line of cliffs 
for a distance of nearly two miles. 
From the evidence presented to our notice in the different contortions 
along the line of cliffs, and which are represented in the sketches, it would 
seem that the rock masses at their original horizontal position at the bottom 
of an ancient ocean must have covered an area more than twice as extensive 
as that which they now occupy. I have taken some trouble to measure 
many of the bent strata and find that in several instances they are squeezed 
into a space less than one-third of that which they occupied in their normal 
condition, and although my calculations must necessarily be vague owing 
to the different degrees in which the beds are inclined, yet there can be no 
doubt as to their former wide-spread distribution as compared with their 
present more circumscribed position. I had, with my son, made a measured 
section of the whole line of coast, but unfortunately it has been lost, so that 
I can now only present to your notice views of detached portions of the 
cliffs. 
The contorted strata near St. Abb's Head, Scotland, have always been 
considered a marvellous example of such phenomenon. There the rocks in 
