EDO4155 - St John Ambulance Hall, North Square, Dorchester, Evaluation Trench 2

Terrain Archaeology carried out an archaeological evaluation of the former St John Ambulance Hall, North Square, Dorchester, during February 2000. Four hand-dug test pits (Trenches 1-4) were excavated (1) (2). Trench 2 measured 2m x 2m and was dug through the sloping bank at the southern end of the site, adjacent to Friary Lane, to a maximum depth of 1.3m in a small 1m x 0.8m sondage in the NE quadrant of the trench. A prehistoric land surface was recorded at the base of the trench; a 0.1m thick layer of reddish-brown clay containing struck flint above the natural chalk. A 0.2m thick layer of reddish-brown clay containing very small abraded sherds of Roman pottery lay above this. A N-S oriented flint and limestone wall was recorded running along the east side of the trench surviving up to 0.3m high and 0.45m wide. A small circular feature in the top of the wall may be a post-hole. A possible floor lay on the western side of the wall, 0.1m thick. The wall was sealed by a hard packed chalk surface which may represent the floor of a later Roman building. A medieval soil sealed the floor, above which lay a hard packed clay and rubble layer upon which a mortared limestone block wall had been constructed. It survived up to four courses high but had been truncated by landscaping associated with the building of the St John Ambulance Hall. The wall appears to be the remains of the north wall of a house fronting Friary Lane which was demolished in the 19th century. The remains of a later wall, parallel to Friary Lane, in the upper part of the Trench probably represents an even later building fronting on to Friary Lane (4). The NE quadrant of this trench was re-excavated in March 2000 by the structural engineers. No new archaeological deposits were disturbed (3).