Part of a Letter from Mr. John Parker, an English Painter at Rome, to His Father at London, concerning the Late Eruption of Mount Vesuvius: Communicated by Mr. Henry Baker, F. R. S.

LXXVIII. Part of a Letter from Mr. John Parker, an English Painter at Rome, to his Father at London, concerning the late Eruption of Mount Vesuvius: Communicated by Mr. Henry Baker, F. R. S. Honoured Sir, I had the satisfaction, whilst at Naples, to see the eruption of Mount Vesuvius, which was very extraordinary; but the want of room here hinders me the giving you any very particular account. It lasted about 25 days in all, and broke out of the side of the mountain; preceded by an earthquake, felt all over Naples at the time of the eruption. The mountain in the middle of the crater or cup, which formerly threw out the stones, sunk down, with about a third of the bottom of the said cup. The breadth of the matter it threw out is in some places half a mile over, in almost the least part 60 feet; and has filled a valley, into which it ran, that might be about 60 feet deep, and raised a mountain in the same place, of matter and ashes, about 50 feet high; and its whole length, from the mouth to where it stopp'd, is about 5 miles; but it did not arrive at the sea by near five miles. The matter, which is here called lava, seems to be composed of iron, antimony, sulphur, and salts, and is not always of the same colour, taste, &c. in every place. The thing I can compare it to most, is the large cinders thrown out of your great iron works, but cover'd over in many places with the above salts and sulphur. Whilst the lava run red-hot, I saw a man throw a mass mass of the cool lava from an height upon it, which, far from sinking into it, rebounded like a ball. Its motion was as slow as the common walk of a man. It broke out in five different places. I walked on it for about a mile, whilst near three feet of the top were cool'd; but for many feet underneath as red to the sight as the furnace of a glass-house. It covered and burnt up trees, houses, &c. in short all it found in its way. From, SIR, Your dutiful son, John Parker. LXXIX. The Case of a Piece of Bone, together with a Stone in the Bladder, successfully extracted by Mr. Joseph Warner, F.R.S., and Surgeon to Guy's Hospital. Read May 28, 1752. THE stone in the bladder is a disease so common to both sexes, and the symptoms, and circumstances attending it are in general so well known, and so much alike, as to render few cases of this kind worthy of communication. But as the following is attended with a singular, and perhaps unparallel'd circumstance, I make bold humbly to offer to your consideration a short account of the following fact: Elizabeth