A Guide to the Mount's Bay and the Land's End / Comprehending the topography, botany, agriculture, fisheries, antiquities, mining, mineralogy and geology of West Cornwall

by John Ayrton Paris

Before our arrival at Saint Michael's Mount, the only intermediate object worthy of notice is the town of Marazion, or Market Jew as it is sometimes called. It stands upon the sea shore, on the eastern shoulder of the bay, and is well sheltered from cold winds by a considerable elevation of land to the north; still, however, as it is exposed to the south-west, which is the prevailing wind, it is far less eligible as a place of residence for invalids than Penzance.

The town contains more than 1100 inhabitants; its principal support, if not its origin, according to some authors, was derived from the resort of pilgrims and other religious devotees to the neighbouring sacred edifice on Saint Michael's Mount; but its name was indisputably derived from the Jews who traded here several centuries ago, and held an annual market for selling various commodities, and purchasing tin, and other merchandize in return. In the reign of Queen Elizabeth it obtained a charter, vesting its government in a mayor, eight aldermen, and twelve capital burgesses, with a power to hold a weekly market, and two annual fairs. In the preamble to this charter it is stated "that Marghaisewe was a trading borough town of great antiquity, and that it suffered considerable dilapidation in the days of Edward VI., when a number of rebellious people entered, and took possession of the town, and laid many of the buildings in ruin." From this disaster the town does not appear to have ever recovered, while from the growing importance of Penzance, the suppression of the Priory, and the loss of the Pilgrims, from whom it derived its principal resources, its consequence gradually declined, until at length it dwindled into its present condition.

It has been asserted on good authority, that under this charter of Elizabeth, the town formerly sent members to Parliament, and Dr. Borlase in his manuscripts, mentions the names of Thomas Westlake, and Richard Mills, Esqrs. as those of the two members who were actually returned for Marazion in the year 1658. It does not, however, appear that they ever took their seats. It would seem, moreover, from some original letters which passed between the Sheriff of Cornwall and the mayor of this borough, during the protectorate of Cromwell, that the inhabitants were solicitous to recover their long neglected rights; but this effort proved ineffectual.

In going from Marazion to the Mount, we pass a large insulated rock, known by the name of the "Chapel Rock," whereon the Pilgrims, who came to visit the Priory of Saint Michael, are said to have performed certain devotionary and superstitious ceremonies, in a kind of initiatory chapel, previous to their admission to the more sacred Mount; there is not, however, the slightest vestige of any masonry to be discovered, and it would therefore seem more probable that it merely derived its name from its vicinity to the shrine of Saint Michael. The rock is composed of well marked Greenstone, resting on a bed of clay-slate, and which, in its direction and dip, will be found to correspond with the slaty rock on the western base of the Mount.

We arrive at Saint Michael's Mount.—The rock of which it is composed is of a conical form; gradually diminishing from a broad, craggy base, towards its summit, which is beautifully terminated by the tower of a chapel, so as to form a pyramidal figure. On its eastern base, is a small fishing town, holding about 250 inhabitants; and a commodious pier,[24] capable of containing fifty sail of small vessels, and which proves to the proprietor of the Mount a considerable source of revenue.

The height from low water mark to the top of the chapel tower is about 250 feet, being 48 feet higher than the monument in London. In circumference at the base, the Mount measures nearly a mile, and is said to contain about seven acres of land; such, however, is the effect of the vast extent of horizon, and the expanded tract of water which rolls around its base, that its real magnitude is apparently lost.

In a mineralogical point of view, this eminence is certainly the most interesting in Cornwall, or perhaps in England; who can believe that this little spot has occasioned greater controversy, and more ink-shed than any mountain in the globe? yet such is the fact; let us therefore before we ascend walk around its base and examine the geological structure which has excited so much attention. The scenery too is here of the most magnificent description; rocks overhang rocks in ruinous grandeur, and appear so fearfully equipoised, that, although secure in their immensity, they create in the mind the most awful apprehension of their instability, whilst the mighty roar of the ocean beneath, unites in effect with the scenery above.—All around is sublime.——But the Geology, enough of the picturesque.

The body of the rock is composed of Slate and Granite; the whole northern base consists of the former, but no where does it extend to any height, the upper part, in every direction, consisting of Granite. On the south side this Granite descends to the water's edge, and it continues to constitute the whole of the hill, both on the eastern and western side, for about three-fourths of its whole extent. Where the granite terminates numerous veins of it appear in the slate, in many different directions; while the granite in its turn, encloses patches of slate. In the vicinity of the former rock the latter is found to contain so much Mica, as to resemble Micaceous Schist, or fine grained Gneiss, for which it has been erroneously taken by some of our earlier observers. And, while at some of these junctions there would seem to be a mere apposition of the two rocks, at others, the intermixture is so complete as to render it difficult to say to which of the two certain considerable masses belong.

Here then is the phenomenon which has invested the spot with so much geological interest. Here is Granite, which Werner conceived to be a primary formation, and around which he supposed all other rocks to have been deposited, if not of a later date, at least contemporaneous, in origin, with slate. How is this anomaly to be explained? De Luc at once asserts what we presume no rational observer can for one moment believe, that the rock of which these veins are composed is not true Granite, but "Pseudo-granite"! Dr. Berger attempts to surmount the difficulty by a different expedient, and declares that they are not veins! but prominences from the granite beneath, which have been filled up by the subsequent deposition of clay-slate. It might, says Sir H. Davy,[25] with nearly as much reason be stated, that the veins of copper and tin belong to a great interior metallic mass, and that they existed prior to the rocks in which they are found. The advocates of the Plutonian theory have, as might have been supposed, eagerly availed themselves of the support which this phenomenon is so well calculated to afford their favourite doctrine. They accordingly affirm that the granite has been raised up through the incumbent slate, into whose fissures it has insinuated itself. Upon these theories we shall offer no comment; it is the humble task of a "Guide" merely to direct the attention of the traveller to the phenomena themselves, and then to leave him to deduce his own conclusions from their appearance. In the fulfilment of this duty we recommend the geologist to proceed to the western base of the Mount, where he will find near the water's edge, what have been considered by Dr. Thomson as "two large beds of granite in the slate, with veins running off from them; the position and appearance of which are such as to leave no doubt but that the great body of the granite has been deposited posterior to the slate formation." Mr. Carne, on the other hand, contends that "these granitic bodies cannot with any propriety be called 'Beds in the Slate;' one of them," says he, "is a granite vein, and although six feet wide near the granite mass, it becomes gradually smaller as it recedes, and dwindles to a point at the distance of 80 feet. The other is a part of the granitic mass, from which some veins appear to diverge; and, in no part does it overlie the slate."[26]