It has been frequently noted by those analysing the 1086 Domesday survey that there are fewer watermills recorded in Cornwall and Devon than might be expected when compared with other counties. This paper puts forward a reason why this is so. It is suggested:
- firstly, that mills were needed in both Cornwall and Devon in the 11th century, and that both counties were probably as well served then with mills in 1086 as were other counties,
- secondly, that many of the mills in the eleventh century in Devon, and all but six of them in Cornwall, were salt water tide-mills rather than fresh-water river mills, and
- thirdly the Domesday survey did not record tide-mills in those counties and very rarely, if at all, listed them in other counties either.
If this were the case it would explain the absence of Domesday mills recorded in those counties with their long indented coastlines in which tide-mills were later located.
In support of this thesis it is suggested:
- that tide mill technology was already well-known and well-established in the British Isles in 1086, and
- that parts of the coast of Devon and Cornwall are particularly suited to the siting and construction of tide-mills, and
- that the mills in Cornwall and Devon that were recorded in Domesday were not on the coast and could not be tide-mills, and
- that in the rest of the country it is difficult to identify any Domesday mills that were certainly tide-mills.