Reasons for Designation
Approximately 10,000 lead industry sites are estimated to survive in England,
spanning nearly three millennia of mining history from the later Bronze Age
(c.1000 BC) until the present day, though before the Roman period it is likely
to have been on a small scale. Two hundred and fifty one lead industry sites,
representing approximately 2.5% of the estimated national archaeological
resource for the industry, have been identified as being of national
importance. This selection of nationally important monuments, compiled and
assessed through a comprehensive survey of the lead industry, is designed to
represent the industry's chronological depth, technological breadth and
regional diversity.
The reverberatory lead smelt mill was developed in the late 17th century, and
marked an important stage in the development of the switch from wood to coal
fuel which rendered the Industrial Revolution possible. The reverberatory
smelt mill was a rectangular enclosed structure of stone or firebrick held by
iron strapping, within which ore was smelted by the heat of flames from a
separate coal fire in one end, reflected down onto the ore by an arched roof.
The separation of fuel from ore made the use of coal possible. A chimney (or
flue to a separate chimney) at the far end from the fire provided the draught
to draw the flames over the ore; no air blast was used and, consequently,
water power was not required. Early reverberatory lead smelt mills consisted
simply of a large barn-like building containing the furnaces, with chimneys
projecting from the outer wall. Late 18th and 19th century smelt mills were
often large complexes containing several smelting furnaces, together with slag
hearths for extracting lead from the slags, roasting furnaces for preparing
the ore, refining furnaces for extracting silver from the lead by a process
known as cupellation, and reducing furnaces for recovering lead from the
residue or litharge produced by cupellation, together with sometimes complex
systems of flues, condensers and chimneys for recovering lead from the fumes
given off by the various hearths and furnaces. Reverberatory smelt mill sites
will also contain fuel stores and other ancillary buildings. Many of the later
sites used water power to provide the air blast for the slag hearths.
Reverberatory smelt mills existed in all the lead mining fields of England,
and also in some coastal areas, using imported ores; about 100 sites are
believed to have existed. Since both the buildings and the sites of
reverberatory smelt mills were more easily reused than those of ore hearth
smelt mills, examples surviving as well preserved field monuments are very
rare nationally.
All early sites with any structural or earthwork remains, and all later sites
retaining a range of structural and/or earthwork features, together with any
sites believed to retain the remains of furnaces, whether as exposed ruins or
as buried stratigraphy, will merit protection.
The Marrick Cupola smeltmill is one of the earliest examples in England for
which any remains are known to survive. The remains are unusually complete
for a monument of this type and date, and the slag tips form an important
source of information for the scientific study of early reverberatory
smelting. The importance of the site is increased by its good historical
documentation and short working life, with little later disturbance.
Details
The monument lies on a modified natural terrace on the north side of Swaledale
and includes the ruins, earthworks and slag tips of an early reverberatory
lead smeltmill.
Construction of Marrick Cupola smeltmill commenced in 1700, and smelting began
in 1701. It was operated by a partnership led by John Blackburne and his agent
Reuben Orton, and smelted ore from a range of mines in the Yorkshire Dales;
coal was supplied both from Wensleydale and from County Durham. From 1704
onwards, the partnership was embroiled in complex legal disputes regarding
the smeltmill and various mines, and by 1723 the smeltmill was abandoned.
The smeltmill itself survives in the form of a ruined rectangular stone
building, measuring approximately 35m by 8m and standing up to 1m high above
modern ground level. It is terraced into the base of a steep natural slope. On
the slope to the north, areas of bare lead contaminated ground indicate the
presence of archaeological deposits associated with the smeltmill, and a
length of rubble, running north from the east end of the building, is thought
to represent the remains of a small flue. To the south and south east of the
smeltmill ruins lie extensive slag tips and to the west is shallow terrace
extending as far as the field wall. The slags are unusual in character and
contain considerable amounts of lead and lead minerals, illustrating the
inefficient nature of early reverberatory smelting, and forming an important
resource for the scientific study of the early development of reverberatory
smelting technology. To the west a prominent access track is cut into the
slope and extends north east from the ruins of the smeltmill to the field
wall.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
It includes a 2 metre boundary around the archaeological features,
considered to be essential for the monument's support and preservation.
