A section of the castle wall between the gatehouse and the eastern city wall was found to be in imminent state of collapse in 1891 and despite efforts to repair it, it fell in October of that year. The unstable part of the wall was that around the site of the circular tower shown on Norden's plan of 1617. It was speculated that when this tower was demolished (at an unknown date), the rebuild was of very poor quality. After the demolition of St Mary's chapel with the other buildings in the late 18th century, a lodge had been built close to the new castle entrance. This lodge was threatened by the unsafe wall and during works to make it safe, excavations in its floor revealed a number of human skeletons which were assumed to have been buried in the grounds of the chapel. Thomas Westcote wrote in around 1630 that the chapel was "ruinous" and a document of 1639 records that Bishop Hall was requested to assign the chapel precinct "for buryall of such Prisoners as shall die in the Gaole."