[523] Hist. August., 21, 39.

[524] Procopius, De Bel. Goth., i, 19; Cassiodorus, Var. Ep., vii, 6. The Porta Maggiore and the so-called Arch of Drusus belonged to aqueducts.

[525] He perhaps equalled Justinian as a builder; Suetonius, Augustus. See the Mon. Ancyr. for a list.

[526] Suetonius and Hist. August. enumerate most of their productions in masonry.

[527] The Baths of Diocletian covered nearly thirty acres, and some others were almost as large.

[528] Cassiodorus, Var. Ep., vii, 13, 15.

[529] The Notitia gives 423 temples, 11 great baths, 11 forums, 36 triumphal arches, 6 obelisks, etc.

[530] Olympiodorus, p. 469. A private circus was an essential part of such establishments; and, of course, a temple, perhaps more than one.

[531] As in the case of Constantius II on his visit to Rome in 356; Ammianus, xvi, 10.

[532] Strabo, V, iii, 8. The ring of wall which formed the base still exists, and has recently been used as a circus.