Now that the plan of Vespasian’s Forum could be precisely fitted into the plan of modern Rome, it became clear that some fragments of large fluted white marble columns, found in the southeastern part of this area as long ago as 1875, belonged to the part of the portico where the larger columns shown on the Marble Plan would fall. Colini now made another join on the Marble Plan, adding to Lanciani’s fragment another piece, previously known but not connected, which showed the Temple of Peace at the back of the portico. It was an apsidal building, wider than it was deep, with a pedestal for the cult statue indicated in the apse. If it survived today it would come within a few feet of touching the north corner of the Basilica of Maxentius. The south side of the rectangular hall to the right of it coincides with the actual wall of the church of Sts. Cosmas and Damian, which was the findspot--in 1562--of the fragments of the Marble Plan itself. This square hall was one of the libraries of Vespasian’s Forum. Since the principle of axial symmetry nearly always operates, justifying the hypothesis that what appears on one side of the axis of a Roman plan will have a twin on the other; and since the Romans usually built their libraries in pairs (one Latin, one Greek), Colini quite reasonably restored on paper another rectangular hall to the left of the apsidal temple. A section of the polychrome marble pavement, excavated by Colini east of the church wall, was less than an inch thick, too thin to be exposed to the weather. Colini inferred that it must have been part of the flooring of the library in which the Marble Plan was displayed. An ingenious combination--“joins” recognized on the Marble Plan, actual excavation, and inference--had now made the Forum’s general outline clear, but Colini was not yet done. Overlying the Forum’s outer (northeast) perimeter wall, as he had plotted it, rose the medieval Torre dei Conti, built by the brother of Pope Innocent III. Re-examining beneath this tower the ancient remains, in squared travertine, ordinary tufa, and _peperino_, Colini was able to establish that they formed part of Vespasian’s Forum, a great ornamental rectangular niche on its northeast side, with two columns of African marble in front of it. Symmetry would dictate another matching niche further to the southeast in the same wall, and a pair on the opposite side to correspond. Pink granite columns found in the excavations belonged to the portico; marble gutters proved that it had a pitched roof. Finally, in 1938, the plan was complete enough for a model of the Forum to be made (Fig. 9.4) for Mussolini’s Mostra Augustea della Romanità, a great exhibition of models and photographs of Roman architecture and engineering, casts of inscriptions, and replicas of artifacts. * * * * *