To return to the Temple of Vesta, which is always the first object at Tivoli. I shall not attempt to describe the beauties of the ruin, because it has been so often done before, and because no description can do justice to the reality; but I will point out a few particulars in the construction, with which perhaps you are not so familiar. The cell is formed of _opus incertum_, which has been described by Vitruvius as a masonry of small pieces of irregular shape, fitted together, and united by mortar. Some writers have supposed that by this term he meant the Cyclopean walls, which are constructed of large pieces without mortar, (of these I shall tell you more hereafter) but his description is sufficiently precise to leave no doubt of his meaning. Of this _opus incertum_ we have reason to think that it was in use in the time of Sylla, and probably much before; and the complaint of Vitruvius, that it was in his time giving way to the _opus reticulatum_, which though neater, was less strong; together with the want of existing remains which are known to be of later date; will justify us in concluding that it was discontinued in the reign of Augustus. There are some letters on the architrave, the remains of an inscription, but all that exists is L. GELLIUS, L. F. There was, I believe, a Lucius Gellius in the time of Sylla, but I cannot now recollect where I met with the name. Now the construction of the walls, and the forms of the capital very much resemble some fragments remaining at Palestrina, belonging to the temple of Fortune, which we know to have been restored and greatly enlarged by Sylla; and at Pompei there are capitals of a similar taste, but evidently much prior to the earthquake which preceded its final calamity; and putting all these circumstances together we may, with some probability, assign this building to the time of Sylla. These capitals are not ornamented with the leaves, either of the acanthus or the olive, but with some which rather resemble those of the _Verbascum sinuatum_; and neither they, nor any part of the building, offer the least trace of Greek taste, as distinguished from that of Rome. We do not find at Rome any examples of similar capitals, except an unappropriated fragment or two of peperino, which may have belonged to the same period. Within the cell is a recess, which seems to have been the work of later ages. It has a large doorway, and a window, both of which are considerably smaller upwards. The material of the _opus incertum_ is a sort of tufo, but the dressings which surround the door and window, together with the external order, and the continued pedestal on which it stands, are of a coarse, calcareous, fresh-water deposit, much resembling travertine. This, in the columns at least, and perhaps everywhere else, was covered with a very thin coat of fine, hard stucco, and the _opus reticulatum_ was probably covered with stucco also, but it must have had more