The Barberini Vase being at present the subject of much speculation, I request the favour of you to lay before the Society some conjectures which have amused me respecting several traits of history apparently sketched in the exquisite Cameos on that elegant piece of workmanship. They are offered entirely subject to correction, and better interpretation. It seems to me, where history is concerned, to be very fair to have recourse to it for the explanation of any piece of art which may be of modern discovery. I learn that this vase was found within a sepulchral monument in the Monte del Grano, at Rome according to the words of the historian, who says, of Alexander Severus, Romæ sepulchrum amplissimum meruit. I shall only add, that, among the figures represented by Bartoli as extant on one of the sides of the grand Sarcophagus, is one whose head and manner perfectly resembles the Jupiter or Guardian Genius, which, in the vase, is contemplating the event of Alexander Severus's existence.