To the scientific visitor, Penzance possesses an interest of no ordinary degree. In the year 1814, DR. PARIS, who was at that time the resident physician, succeeded, through the support of the nobility, gentry, and mine agents of the county, in establishing a society for the cultivation and promotion of mineralogical and geological science; and, when we consider the immense advantages of its locality, the ability of its members, and the zeal and munificence of its patrons, we cannot be surprised to find that the short period of nine years has been sufficient to raise it to a respectable rank amongst the eminent institutions of this country. His present Majesty, having graciously condescended to become its patron, it is now denominated the ROYAL GEOLOGICAL SOCIETY OF CORNWALL. The Marquis of Hertford, Lord Warden of the Stannaries, and The Right Honourable Lord De Dunstanville, are its Vice-Patrons, and Davies Gilbert, Esq. M.P., the President; while amongst its officers and members it has enrolled the names of many individuals of the first rank and science in the kingdom. Two volumes of the Society's Transactions are already given to the public, from which a fairer estimate may be formed of the value of its labours, than from any sketch which the limited pages of this "_Guide_" could possibly afford; we shall, however, for the information of our scientific readers, present, in the _Appendix_, a list of the different memoirs which each volume contains. The splendid and extensive series of minerals, already exceeding four thousand specimens, which are deposited in an elegant and spacious museum,[15] offers a most honourable and durable testimony of the zeal and talent with which this department has been conducted; while to the student in mineralogy it affords a most desirable and solid system of instruction; indeed it has already excited such a spirit of inquiry among the miners, as to have led to the discovery of several minerals before unknown in Cornwall. There is also an oeconomical department, containing specimens in illustration of the various changes which the ores of Tin, Copper, &c. undergo in the processes of dressing and smelting. Models are likewise to be seen of the machinery which is employed in such operations. The whole has been admirably arranged under the skilful direction of the Curator, _E. C. Giddy, Esq._ In the geological department of the Museum are complete series of specimens illustrative of the serpentine formation of the _Lizard_,--of the slate formation of the "_Land's End District_,"--of the limestone formation of Veryan, and of the hornblende rocks of St. Cleer near Liskeard. There is besides an interesting series of "_Elvans_"[16] from different levels in many of the principal mines of the county, together with a collection of veins of metallic and earthy substances.