Cornwall's medieval archaeology is somewhat lacking for its greatest industy: Tin Mining.
The remains of a late medieval blowing house can be found adjacent to the stream in the steep sided valley of Bosahan Wood, near Constantine. This is recorded by its latin: "Molendinum Sufflacticum" in a court roll for the manor of Merthen in 1506.
Charles Henderson, the late Cornish historian, records:
"Retallack was part of the lease-hold lands of the manor of Merthen in 1506, the tennant being
Nicholas Pentacost, at a rent of 34/8. There was also a Blowing-house or Tin smelting work
there at this time. In 1545 John Pencoste bought part of the coppice wood at Merthen,
possibly for use in the furnaces at Retallack." (Henderson, 1927, 121).
and:—
"There was an ancient Blowing-house at Retallack mentioned as a "Molendinum
Sufflaticum" in 1506. The old ridgeway coming from the North by way of Lestrainess and
Maen-Rock to the ford at Retallack was probably the reason why the Blowing-house was
established here." (Henderson, 1927, 228).
The site was recorded by other authors but the first and presently only archaeological survey was undertaken in 1984 by Sandy Gerrard et al. It represents the best example of medieval tin smelting archaeology south of Dartmoor.
Data courtesy of Ben Sum, Helston (15/5/20).
RIC = Royal Institute of Cornwall, Truro
References:
Henderson, C., 1927 "A History of the Parish of Constantine in Cornwall"
Gerrard, S, 1984 "Retallack: a Late Medieval Tin Mining Complex in the Parish of Constantine, and its Cornish Context", Cornish Archaeology, No.24