A large portion of this parish is situated on granite, the boundary line of which extends from near the church, in a semicircular form, to Buryas Bridge. South of this line the parish consists of felspar, hornblend, and actynolite rocks, all of which occur both in massive and in schistose forms. A fine instance of the latter may be seen at the back of the quay at Penzance, and may be traced for some distance in a westerly direction on the sea shore below high-water mark. About half way to Newlyn another bed of porphyry, or an irregular continuation of the former, was a few years since explored for tin, and became the celebrated Wherry Mine, yielding not only a large quantity of tin, so as to afford profit after paying the expenses of a
steam-engine, but also beautiful specimens of rare metallic minerals. For an account of this curious submarine mine, Mr. Hawkins’ Paper in the Transactions of the Cornwall Geological Society, vol. 1, p. 127, may be consulted; and in the third volume of the same work, p. 166, will be found an account of the sand bank and submarine forest existing near the same spot (by Dr. Boase. Ed.). Every part of this parish appears to be intersected with metalliferous veins; some copper and small quantities of lead have been raised, but tin is the only metal that has yet proved of importance.
To the above the Editor must add, that Penzance has the good fortune to possess a geological and mineralogical treasure peculiarly its own.
In the year 1814 Doctor Paris and Mr. Ashurst Majendie began to institute the Geological Society, and to form a museum. The Society has flourished far beyond any expectation that could have been originally formed; and the collection has been enriched by the liberality of Mr. Carne, Dr. Barham, Mr. Henwood, and others; but, above all, by Doctor Boase, who has deposited specimens from all parts of Cornwall, collected on an actual survey extended to each individual parish. All these specimens are arranged, labelled, and numbered, with reference to their localities and to his admirable work.
For the general arrangement of the cabinet, with indexes, &c. the Society and the public are indebted to the ingenuity and industry of the late Mr. Edward Giddy; and the room of the Cornwall Geological Society at Penzance may justly be pointed out to scientific strangers as the object most worthy of their attention throughout the whole extent of the country.
MAKER.
HALS.
Maker Vicarage is situate in the hundred of East, and hath upon the east Plymouth Harbour and St. Nicholas Island, north Millbrook and East Anthony, south and west Rame and St. John’s.