AttestedDevionisso at position 10 in the Ravenna Cosmography

Where:  Somewhere in Cornwall, best guess near Fowey, around SX1352.  This is because the Roman forts at Duriarno (Nanstallon, near Bodmin) and Statio deventiasteno (Restormel, near Lostwithiel) controlled a key trans-isthmus portage that linked the river Camel in the north with the river Fowey in the south.  If Pilais can indeed be identified with the north-coast entry to the sea in Padstow Bay, it makes sense to look for a counterpart on the south coast, though no significant Roman archaeology appears to be known from the Fowey area.

Name originDevionisso begins like the river name Deva/Διουα, rather like Cornwall's former Devy and Dewey (Ekwall (1928:125), which flow ultimately into Padstow Bay.  Then -onisso contains the ending -ωνης of numerous Greek words for merchants engaged in buying and selling commodities, or for officials who regulated trade.  This analysis discounts Latin devio ‘to deviate’ and deveho ‘to carry away’ as less relevant, along with Cornish devr ‘water’.  It also discounts an ending based on PIE *neigw- ‘to wash’, from which came English nixie ‘water spirit’, Sanskrit nedati ‘to flow’, and Greek νιζω ‘to wash’.

Notes:  There was a powerful economic drive towards portages (plural) across the south-west peninsula of Britain, because early sailing ships faced great difficulty and danger in rounding Land's End, but there is no hard evidence to suggest which particular river systems predominated at different points in history.  One candidate to be Devionisso was near St Michael's Mount, for a portage across to the river Hayle and St Ives.  A better candidate was near modern Devoran, well inside Falmouth harbour, towards Truro, and not far from modern Devichoys Wood.  The river Carnon there used to be navigable a long way upstream, into the heart of the Gwennap district where tin and other metals including copper have been assiduously mined since deep in prehistory, until 1620 quite large vessels could still go 3 km upstream to Bissoe.  In mining districts Roman-era river configurations are hard to guess, because such prodigious quantities of mine tailings got displaced into river valleys, as in Roman Spain (Bird, 2004).  Silt in the river Carnon is now many metres deep and it is fair to guess that the upper Fowey, preferred here, was also navigable much higher upstream in Roman times.  (Ekwall, 1928:164) suggested that the name Fowey (with earliest English forms like Fawe in 1210) might descend from a Latin precursor such as vario ‘to change’.  (Compare Varis).

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Last edited 7 April 2020     To main Menu.