My LORD, Your Lordship's Most obedient and most humble servant, WILLIAM HAMILTON. * * * * * Naples, February 3, 1767. Since the account of the eruption of Mount Vesuvius, which I had the honour of giving to your Lordship, in my letter of the 10th of June last; I have only to add, that the lava continued till about the end of November, without doing any great damage, having taken its course over antient lavas. Since the cessation of this eruption, I have examined the crater, and the crack on the side of the mountain towards _Torre dell' Annunciata_, about a hundred yards from the crater from whence this lava issued: and I found therein some very curious salts and sulphurs; a specimen of each sort I have put into bottles myself, even upon the mountain, that they might not lose any of their force, and have sent them in a box directed to your Lordship, as you will see, by the bill of lading: I am sure, you will have a pleasure in seeing them analyzed[5]. I have also packed in the same box some lava, and cinders, of the last eruption; there is one piece in particular very curious, having the exact appearance of a cable petrified. I shall be very happy if these trifles should afford your Lordship a moment's amusement. It is very extraordinary, that I cannot find, that any chemist here has ever been at the trouble of analyzing the productions of Vesuvius. The deep yellow, or orange-color salts, of which there are two bottles, I fetched out of the very crater of the mountain, in a crevice that was indeed very hot. It seems to me to be powerful, as it turns silver black in an instant, but has no effect upon gold. If your Lordship pleases, I will send you by another opportunity specimens of the sulphurs and salts of the Solfa terra, which seem to be very different from these. Within these three days, the fire has appeared again on the top of Vesuvius, and earthquakes have been felt in the neighbourhood of the mountain. I was there on Saturday with my nephew Lord Greville; we heard most dreadful inward grumblings, rattling of stones, and hissing; and were obliged to leave the crater very soon, on account of the emission of stones. The black smoak arose, as before the last eruption; and I saw every symptom of a new eruption, of which I shall not fail to give your Lordship an exact account. LETTER II. To the Right Honourable the Earl of MORTON, President of the Royal Society. Naples, December 29, 1767. My LORD,