430 Mr. Winch on the Geology of Lindisfarn. [Dec. 
the cliff called the Red Brea, the stratum covered by the sea at 
low water is of coarse-grained yellowish-brown micaceous sand- 
stone, becoming brick-red when in a state of oxidation. The 
Red Brea does not excede 30 feet in height, 20 of which consist 
of diluvium, two of coarse-grained micaceous sandstone, one of 
bituminous shale mixed with fragments of coal, two of sandstone 
like the former, and five of shale. The strata on this side of the 
island also undulate. Emanuel Head is what seamen call a 
green bluff; its extremity is protected by an accumulation of 
boulder stones. To the west of this headland, limestone and 
sandstone become the prevailing rocks, but the haven in which 
the coves are situated is the most advantageous point for observ- 
ing their construction. The coves are recesses hollowed out in 
the soft sandstone of the perpendicular cliff by the action of the 
sea and the weather, their harder covering having withstood 
these powerful agents. The principal cove is supported by two 
natural pillars, by which its entrance is divided into three pretty 
regular arches, the centre one being much the largest. The 
cliffs here, including their covering of earth, are about 40 feet 
high: the first bed of limestone is four feet thick, of a pale ash- 
grey colour, containing the encrinal fossil and bivalves, and 
breaking into cubic fragments; it is divided from the second 
bed by eight inches of black bituminous shale filled with encri- 
nites; the second limestone is also four feet in thickness ; its 
colour is dark iron-grey, and obscure traces of organic remains 
may be seen init. To this succeeds a thin layer of shale, then 
three feet of reddish micaceous sandstone, and 10 feet of 
exceedingly fine-grained white micaceous sandstone. In this 
soft rock the coves, three in number, are excavated ; their floor 
is of red'and white laminated micaceous sandstone, over which 
the tide flows at high water. At the extremity of the rocks at 
Snipe Point, which forms the western side of the haven at the 
coves, the undulation of the strata may be seen to the greatest 
advantage, and might be compared to the waves of the sea, but 
their curves are too regular, passing across the inclination of the 
beds at right angles, which is to the south-east. This limestone - 
comprises 12 distinct strata, measuring in all 16 feet; the whole 
of these are exposed to view at low water, having been broken 
across by the violence of the ocean. Its position is below the 
sandstone at the coves, and above a red and white sandstone in 
the outer part of the haven to be seen ofily when the tide is quite 
low. The limestone first makes its appearance on the beach 
north of Snipe Point, and is again lost near Emanuel Head. 
Between its first and second strata, which are each a foot thick, 
is enclosed a bed of shale of the same thickness, containing 
mineral charcoal, but 1 was never able to detect vegetable 
impressions in the shales of this island, though casts of euphor- 
bize are not rare in the sandstones. ‘lhe colour of the limestone 
is smoke-grey, and bivalves and encrinites are dispersed through 
