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the cliff called the Red Brea, the stratum covered by the sea at low water is of coarse-grained yellowish-brown micaceous sandstone, 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 observing 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 ashgrey 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 encrinites; the second limestone is also four feet in thickness; its colour is dark iron-grey, and obscure traces of organic remains may be seen in it. 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 only 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 I was never able to detect vegetable impressions in the shales of this island, though casts of euphorbiæ are not rare in the sandstones. The colour of the limestone is smoke-grey, and bivalves and encrinites are dispersed through

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it. From the outer part of the reef on the north side of the haven at the coves, a dyke crosses the strata, and passing through the rocks below the southern point may be again observed on the beach beyond it. The chasm is six feet wide, and filled with limestone in distinct concretions, the colours of which pass from dark reddish-brown to greenish-white, mixed with small veins and minute crystals of white calcareous spar in druses.

That sand hills cover the Snook I have already mentioned: from thence to the neighbourhood of the town, the shore is low, and gradually declines into Fenham Flats without rocks protruding from below the soil; but at a short distance within the line of sand, an extensive quarry has been worked in fine-grained white micaceous sandstone.

Approaching the town, a cliff of shale rises gradually from the north, till its perpendicular face measures about 30 feet, of which 8 or 10 are diluvium: this bank terminates close to the Heugh. The shale is bituminous, and, from exposure to the atmosphere, is fragile, and of a reddish-brown colour. Two bands of clay ironstone, each four inches thick, traverse it horizontally, and nodules of the same ore, enclosing septariæ and such plates as the pitmen call girdles, together with cubic pyrites, are scattered through the whole rock. From the same shale at the foot of the cliff, fragments of the encrinal fossil, formerly highly prized under the name of St. Cuthbert's beads, occur in abundance. Of a shaft that was sunk near this spot, I could obtain no further information than the seam of coal penetrated to, being only 14 inches in thickness, was not worth working, though fuel is a great desideratum both for house use, and for burning lime. It is either imported from Newcastle, and subject to a duty, or is brought in small carts from the vicinity of Berwick. Having finished the survey of the coast, little remains to be added. except that tradition points a low field between the town and the basin, as the spot from whence the stone is said to have been quarried for the erection of the abbey; it is chiefly of a dirty brick-red colour with small spangles of mica, and though fine-grained and soft, has resisted the action of the elements remarkably well. The millstone grit does not appear in situ, though it creeps out on the main both to the north and south of the island. From good authority I learn, that glass tubes similar in composition, but smaller in size, to those found at Drig, in Cumberland, have been detected in sands on the shores.

Without woods, moorlands, or rivulets, Lindisfarn of course possesses a scanty Flora; yet from its slender store, a few plants may be selected worthy the notice of botanists unaccustomed to examine such as are indigenous on our sea shores. Cryptogamic species are peculiarly scarce, with the exception of marine

This dyke was first noticed by Mr. Culley.

algæ, but these being common on all the northern coasts, and already mentioned in the Botanist's Guide through Northumberland and Durham, need not be recapitulated.

Plants on the Heugh and Castle Rock.

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Statice Limonium. Its northern limit on the east coast.

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*To this accomplished botanist, the Flora of Northumberland is indebted for the discovery of Linnæa borealis, growing together with Trientalis europæa and Pyrola minor var. rosea, in a fir plantation on the edge of the moors at Catcherside, four miles west of Wallington, Nuphar minima of Eng. Bot. Nuphar Kalmiana of Hooker's Flora Scot. in Chartner's Lough. On the moors in the same vicinity, Pyrola media, near Roadley Lake, and Gyrophora pustulata, in abundance. On the millstone grit rocks called Shaftoe Crags, Bolton mentions the neighbourhood of Halifax as a locality of this lichen, and the Rev. John Harriman gathered it near Irton Hall in Cumberland; but to Northumberland, it is new; nor has it been found iu Durham.

In the Fields and Pastures.

Convolvulus arvensis, rare;

Carduus arvensis flore albo, common;

Delphinium consolida; field near the Lough House, rare;
Salix mollissima. In hedges.

Agaricus campestris,

Agaricus Georgii,

Agaricus orcades,

Agaricus aurantius.

abundè.

Through the kindness of a young lady who frequently visits Lindisfarn, I am enabled to subjoin the following list of shells. It was taken from a collection made by her during the summer months, when good specimens can be procured from the fishermen's lines, such as are cast on shore being generally broken and spoiled. By the enumeration, the conchologist will be enabled to form a tolerably correct idea of the species afforded by this sea. The names are those used in Dillwyn's Descriptive Catalogue.

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Mactra piperata,

M. Boysii; W. C. Trevelyan,
Esq.

M. lutraria,

Donax truncatulus,

Venus fasciata,

V. casina,

V. scotica,

V. islandica,
V. spuria,
V. exoleta,
V. decussata,
V. perforans,
V. virginea,
Arca Nucleus,
Ostrea maxima,

O. varia,
O. sinuosa,
O. obsoleta,

O. opercularis,

O. edulis,

Anomia Ephippium,
Mytilus rugosus,

M. edulis,

M. incurvatus,

M. subtruncata; W. C. Tre- M. modiolus,

New Series, VOL. IV.

M. anatinus, in the Lough,

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Pennant has given an account of the birds which breed on the Farn Islands, and of course are to be met with on these shores. However, it may be worth mentioning, that this is the most southern spot where the eider duck is known to rear its young. The small Lough on Lindisfarn is the occasional resort of wild swans, geese, widgeons, seal, &c. The wild duck is here a native, and the domesticated sheldrake may be seen in company with the tame ducks. The larger seal, phoca barbata, inhabits the rocks of the staples and farns; and the lesser seal, phoca vitulina, the shoals of Lindisfarn.

I shall conclude by observing, that strangers visiting Holy Island, should not attempt to pass over Fenham Flats till the tide has ebbed between two and three hours, or when it is within the same space of time of high water, especially if the weather be foggy. I am, Sir, yours truly,

N. J. WINCH.

ARTICLE IV.

On the Greek Fire. By the Rev. J. J. Conybeare, MGS.

IN

(To the Editor of the Annals of Philosophy.)

Bath Easton, Nov. 5, 1822.

MY DEAR SIR, In your number for November, you have inserted the substance of a very ingenious essay by Dr. Macculloch on the Greek Fire. I venture, therefore, to transmit the following remarks in the hope that they may contribute somewhat more to the illustration of this curious subject, and to the amusement

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