We now return along a modern path which runs under the grounds of the Villa Mills towards the domus Gelotiana described above. A curved terrace occupies the upper edge of the hill, along which probably ran a portico commanding a view over the southern part of Rome and the Trastevere. At the back of this are the buildings called the Villa Mills from their former possessors, now occupied by a nunnery, and therefore inaccessible to the public. In the year 1777, the plan of the ancient buildings which stood here was explored by Rancoureuil. They consist of a court surrounded with columns and suites of chambers. Parts of the main front looking towards the circus remained till the year 1827. The brickwork of these ruins has induced Cav. Rosa to assign them to the Augustan Age and to call them Domus Augustana. No sure evidence has, however, been discovered for this, and it seems more probable that the Domus Augustana was nearer to the Forum Romanum.[14] [Sidenote: Academia and Bibliotheca.] Passing back again by the ruins called the Domus Gelotiana as before described, we turn to the right and ascend the side of the hill. On the higher level at this point are the ruins of two buildings to which the names of Academia and Bibliotheca have been given by Rosa. In one of these the remains of semicircular ranges of seats and a platform have been supposed to be recognizable, and here may have taken place the recitations and discussions mentioned by Pliny as constantly kept up in the imperial palace.[15] [Sidenote: Ædes Publicæ.] Behind these rooms stand the ruins of a portico, built upon substructions of an earlier period, with Corinthian columns of cipollino, probably forming the side of a small courtyard. Here it may be seen through an opening in the ground to what a depth the substructions of this part of the Palatine buildings descend into the depression or intermontium which originally separated the two parts of the hill, and was filled up by the Flavian emperors. We now enter the range of reception rooms commenced by Vespasian when he destroyed Nero’s golden house, and built by Vespasian and his sons, Titus and Domitian, at the same time with the Coliseum. These are raised on gigantic constructions of opus quadratum to the level of the rest of the Palatine Hill. Many stamps on the bricks found here seem to show that the buildings were finished by Domitian. [Sidenote: Triclinium.]