Excavation

Date February 1991

Event ID 828922

Category Recording

Type Excavation

Permalink http://canmore.org.uk/event/828922

NS97NW 46.04 9260 7951

NS 9259 7955 The points where the Rampart of the Antonine Wall crosses the West Burn of Falkirk (NS87NE 57.00) and the Polmont Burn were uncovered as a consequence of development threats. The two streams differ greatly in size, the West Burn of Falkirk being much smaller. This has led to different solutions being applied by the Roman engineers in designing the two crossings. The excavation at Beancross in 1986 for Falkirk Museum had indicated that the Roman frontier at Dollhouse lay further S than had been indicated on OS maps (Keppie et al. 1995). It was also known that the Military Way (NS97NW 46.10) crossed the low-lying ground to the rear of the Wall (Macdonald 1934).

Deposits on the west side of the trench were consistent with the slow silting and westward migration of a medium-sized watercourse. The natural slope down from east to west on the eastern half of the trench may be seen as one of this stream's banks. The close proximity of the Polmont Burn in its present canalised course leaves little reason to doubt this interpretation.

Three groups of stonework were also revealed (see NS97NW 46.10 for description of the third group). The most northern group was a large area of stonework and had a clear channel running through it. The character of this foundation, its width of 4.2m and its location all indicate that it formed part of the Antonine Wall. A second foundation comprised of large boulders around which smaller cobbles had been packed. A small cut divided this group from the northern one, however there was evidence of contemporaenity. These were both terraced carefully into the ground to provide level foundations. The stones in the N group can be seen as a single foundation running E-W, stepped into the E bank of the old stream. The W part of the foundation survived because of the natural dip in the ground, whereas eastward it had evidently been removed by later cultivation such as was noted by Gordon (1726). Unfortunately the very point at which it reached the burn had been removed by the cutting of the sewer pipe trench.

The channel through the Wall foundation were seen in a similar position at West Burn of Falkirk where their function has been interpreted as overflows redirecting water back into the burn. However, the channel here had the occurrence of small stone chippings at its S end, in which it would seem unlikely that it would also function as a conduit for water. Also the position of the stonework immediately to the S would render this task impossible, thus this channel can best be interpreted as a slot for a horizontal timber beam. Its location suggests that it would have been the sill beam of a wooden bridge over the Polmont Burn. Similar circumstances of lateral wooden sleepers are discussed by Ward (1903), Macdonald (1937) and Johnson (1983). This type of construction could be used for rivers up to 15m wide.

G B Bailey 1996

A Gordon 1726; L J G Keppie, G B Bailey, A J Dunwell, J H McBrien, K Speller 1995; G Macdonald 1934; J Ward 1903