* an aqueduct which takes its name from its con- structor, Alexander Severus (Hist. Aug. Alex. Sev. 25; cf. THERMAE NERONIANAE
; Not. app., Pol. Silv. 545, 546). It seems to be referred to as forma Iovi in a document of 993 A.D. (Reg. Subl. No. 105, p. 151).
The springs were used by Sixtus V for the Acqua Felice (1585-7), but the whole course of the aqueduct was only identified in the seventeenth century by Fabretti (de aquis, Rome, 1680)
, whose accurate description of its interesting remains is followed by LA 380-393 ; LR 56. Its course from the third mile of the via Labicana towards the city is quite uncertain, and the 'nymphaeum Alexandri,' the so-called 'trofei di Mario,' is the terminal fountain of the AQUA IULIA
(q.v.); though the piscina of the Vigna Conti, generally attributed to the THERMAE HELENIANAE
(q.v.), may have belonged to it (LF 32). Cf. Jord. i. 1
. 477-479; HJ 247-248, 350.