The direction of striae on the underlying quartzitic rocks, particularly well seen near the Douglas colliery, Balmoral, point to an ice movement from the north-north-west to south-south-east.
Thirteen miles south-south-east is the Sorgente Mefita, identical with the pools of Ampsanctus.
The orientation of each was from west-south-west to east-north-east, one being south-south-east of the other.
The length of the west side, where the line of direction is from south-south-east to north-north-west, is about 215 yds.
The ends of the basin at northnorth-west and south-south-east were adorned by very small open temples, each with a circular colonnade of eight pillars.
