The Piercebridge formula in the North-East of England : an assessment and alternative method of supply to the Roman army
This thesis tests a recent theory of Roman military supply in the North-east of England. The Piercebridge formula (Selkirk, 1983) involves a system of Roman forts provisioned by barges along rivers made navigable by a series of dams, locks and canals. The formula is first assessed on a theoretical basis: as a comprehensive road system was built across Britain during the Conquest period, construction of Piercebridge formula components for river-borne fort supply would have been justified only if the Piercebridge formula was significantly more efficient than overland transport. To this end, the efficiency of Piercebridge formula river-borne fort supply vis-a-vis the efficiency of overland fort supply is assessed in a survey area comprising the North-east of England. Evidence for the Iformulal is then assessed at ten sites across the North-east. A second aim of this thesis is to present an alternative to the Piercebridge formula method of supply to forts in the North-east. This alternative method involves sea-borne transport to ports serving the North-eastr overland transport by ox-cart and pack animals along the Roman as well as native road systems, and river transport upon barges and other craft when such rivers were naturally navigable.