Large Roman drain discovered, emptied for a distance of 200 yards at the S of the Postern Gate (see 12236). At its S end was a small building taken to be a bath because of the spring that rose inside it. This structure was thought by Hull to be a Mithraeum but further work disproved this - it is possibly a Roman waterworks. <1> Other ref given in source 1. <2> Impressive drain common to Insulae 7 and 14. It begins at the NE corner of the `Mithraeum' (see above) and after a vaulted and serpentine length ran along the W side of the street, nearly straight to the NE gate. There it turns under the street and runs out through the gate to curve sharply to the left and empty itself apparently into the town ditch. Its purpose may have been to run off flood water. Detailed description of the drain given in this source, also of pottery and coins found. The construction is of tiles laid in white mortar `the vaulting though carelessly done is soundly buit'. The fill of the drain appeared undisturbed - in the S part there were deposits up to 15" thick of layers of washed sand and mud. Finds included pottery and one coin - an as of Hadrian. The accumulation dates from the end of the C1, slowly at first, more rapidly in the Antonine period. Duncan mentions coins of Carausius, one of Domitian and several of Constantine. <3> <4> <5> Four photos in source 1.