>perhaps what Mike was asking is were the smelting sites outside the enclosed
>and cultivated land on the common or waste.
Martin,
As far as can be determine, although the manorial records for Bere Ferrers
in the late medieval period have not survived, some of the bole sites were
operated in close proximity to cultivated ground. The major area of
unenclosed / common land is in the centre of the parish, to the east of Bere
Alston, well clear of the mining / smelting areas closer to the Tamar. For
the period 1301-16 the main smelting / refining site was at Calstock, on the
Cornish bank of the Tamar, immediately south of the church - evidence has
turned up in the new burial ground. Now the church there is on a ridge of
high ground so was at the limit of cultivation but the lead / sulphur plume
from smelting must have been in evidence in and around the churchyard
itself. Some manorial records do survive for Calstock but I have never come
across reference to the poisoning of land.
>The only problem about soil sampling would be the number of samples need to
>locate a small discrete site such as a bale/bole. It could end up being a
>needle in a haystack exercise. A vegetation survey might be more profitable
>identifying the presence of lead tolerant plants.
The North Derbyshire survey I referred to was quite effective in identifying
the later boles of the area - much larger hearths than those employed in
south Devon - although it was not planned as an archaeological exercise.
Identifying metalliferous flora might be a problem on land which has been
farmed intensively over the last century and it is c.600 years since the
boles were in action.
However the amount of lead smelted in the south Devon mines at Bere Ferrers
was not insignificant - the mines sold at least 760 tons of sterile lead
between 1304 and 1317 as a by-product of silver mining operations. The
majority was produced using techniques which were relatively inefficient for
lead recovery - up to 28 percent would be lost in the refining process
alone. So there was probably several hundred tons of lead distributed across
the area during that 13 year period.
>Because of differences in the smelting technology
>might it be possible to distinguish bale smelting from ore hearth smelting
>residues?
No idea - but it could be tested as we are fairly sure where the ore hearth
smelters were in the 16th-17th centuries, and the reverberatory furnaces in
the 19th century are well documented, at both Bere Ferrers and Combe Martin.
Peter
______________________________________________
Peter Claughton, Blaenpant Morfil, Rosebush, Clynderwen,
Pembrokeshire, Wales SA66 7RE.
Tel. 01437 532578; Fax. 01437 532921; Mobile 07831 427599
University of Exeter - School of Historical, Political and Sociological Studies
(Centre for South Western Historical Studies)
E-mail: [log in to unmask]
Co-owner - mining-history e-mail discussion list.
See http://www.jiscmail.ac.uk/files/mining-history/ for details.
Mining History Pages - http://www.exeter.ac.uk/~pfclaugh/mhinf/
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