National Geographic : 1957 Apr
Perjurers Beware! Mouth of Truth May Bite a Liar's Hand The ancients carved this marble face to cover a well. Now the hollow eyes stare from the portico of the Church of Santa Maria in Cosmedin. In medieval times suspected perjurers were dragged before the image as a test of honesty. The mouth was reputed to gnash the hand of the guilty. Fountain of the Rivers . . . This Bernini-designed foun tain anchors an obelisk that once adorned the Circus of Maxentius. Figures symbolize the Ganges, Danube, Nile, and Plate Rivers. Seventeenth century Rome flooded the piazza for water sports.