was erected to the memory of Constantine's daughter, Constantina, who
was anything but a saint according to Marcellinus. It is worth
visiting on account of its dome, supported by twenty-four clustered
columns in granite, and covered with mosaics. The sarcophagus is now
in the Vatican Museum.
S. Costanza is a mausoleum and a baptistery, not properly a church.
The mosaic pictures of the fourth century are the finest known of that
period. Those over the doors are of the eighth century.
"At this time [A.D. 360] Julian sent the body of his wife Helen,
recently deceased, to Rome, to be buried in the suburb on the road to
Nomentum, where also Constantina, his sister-in-law, the wife of
Gallus, had been buried" (Marcellinus, xxi. i. 5).
_A quarter of a mile beyond the church, on the left, is the entrance
to_