Treryn Dinas

In the Parish of St. Levin, in this County, there is a Promontory, called Castle-Treryn. This Cape consists of three distinct Groupes of Rocks. On the Top of the middle Groupe of Rocks, (which we climbed with some Difficulty and Hazard) we there observed the most wonderful Logan-stone, perhaps, in the World; one of our ingenious Companions took the Dimensions of it, and computed the solid Content, which amounted to about 95 Tons; the two inclined Sides somewhat resemble the two Roofs of a House, meeting in a sort of obtuse Ridge upon the Top. The lower Part of the Stone is a large plain Base, near the Middle of which, projects a small Part on which it rests, which Part seemed to be of a round Form, and not to exceed more than 18 or 20 Inches in Diameter. The lower Part of this too, was somewhat convex'd, by which Means, as it was equally poised on this Part, it became easily moveable upon the large Stone below, the Position of which was most of all wonderful, as the Surface on which the Logan-stone rested was considerably inclined; so that at first Sight, it seemed as it were easy to heave the Logan-stone off, but on Tryal, we found, that we could produce no other Motion than that of Libration, the Power of one Man being only sufficient to move it up and down about half an Inch. It is so high from the Ground, that no one who sees it, can conceive it could be lifted up to the Place where it now rests. It makes a natural Part of the Crag on which it at present stands, and always seems to have belonged.