1. Ground plan of the Basilica of St. Agnes, with a portion of the staircase by which it is reached; fourth century.
2. Plan of the upper story, on a level with the galleries.
3. Longitudinal section through the portico, nave, and apsis.
4. Transverse section, showing the tabernacle (ciborium), supported by four columns of porphyry.
5. Base and portion of shaft of one of the columns of nave taken -from some antique monument, and remarkable for its precious material and perfect execution.
6. Antique ornament which forms the cornice round the tribune or apsis.
7. Plan of the Church of St. Constance at Rome, near the Basilica of St. Agnes, commonly called the Temple of Bacchus. The columns are coupled in the direction of the radii of the circle, instead of on the line of the circumference.
8. Transverse section of the Church of St. Constance, where the coupling of the columns may be seen.
9. Plan of an antique temple converted to a church -- S'a Maria Maggiore at Nocera de Pagani, on the road from Naples to Salerno.
10. Section of the antique Temple of Nocera; in its circular form and coupling of the columns it resembles the Church of St. Constance, Nos. 7 and 8.
11. Plan of the Church of St. Martin, near Bonn, resembling both the Church of St. Constance and the Temple of Nocera.