Coombe Gill Mill

Coombe Gill Mill

Water-powered cornmill of the early 18th century with possible earlier origins, and an attached corn drying kiln, probably of the 18th century.

The mill is constructed of rubble stone with large alternating quoins, beneath pitched roofs of slate laid in diminishing courses. Weighting stones hold down the eaves. The rectangular mill building is oriented roughly east to west and stands on the eastern bank of Coombe Gill, a tributary of the River Derwent. An attached rectangular corn drying kiln projects north from the north wall, with a north lean-to and a wheel pit containing a waterwheel attached to the west elevation.

The east gable features a long, centrally placed timber lintel with a slate drip mould above. This formerly housed an original double-width entrance; today a single opening is fitted with a timber boarded door, and a window stands to the right. A brass plaque screwed to the lintel records a deed of 1724. The south elevation has a single inserted window at the left end. The massive west gable retains evidence of several phases and contains an attached stone wheel pit with a six-spoke waterwheel fitted with an iron shroud plate, flaunch, timber axle, spokes, buckets and sole plate. To the right is an inserted glazed casement window with a narrow timber lintel and stone sill. The north elevation is of substantial build with remnants of a timber lintel and a small blocked window beneath the eaves, though it is mostly obscured by the attached kiln. The corn drying kiln's east and west elevations each have a single small window just below the eaves, and the north-east corner is curved. The asymmetric north gabled elevation has a rectangular window positioned a little to the right of the apex with a drip mould below, and an attached lean-to addition beneath.

Internally, the mill retains its original simple plan-form with exposed, painted rubble walls and a boarded ceiling. The west wall is slightly bowed with a rough horizontal slab mid-way up indicating the former presence of the internal waterwheel. A rough plinth with projecting stones probably supported the timber superstructure that formerly housed the milling apparatus. The waterwheel axle entered through an aperture considered to lie below the present floor level. The original mill bedstone with a flat circular lip has been reused as the base for a stove. The central truss of the original roof structure is visible, with principal rafters hafted together at the apex and jointed to the tie beam with a pair of vertical braces rising from the top of the beam to the undersides of the principals. The timbers were hewn with an adze rather than sawn, and assembly marks on the western face of the tie beam coincide with the mortice and tenon joints for the two braces. The initials 'DJ', presumably of one of the Daniel Jopsons who owned the mill between 1741–1817 and from 1861 into the early 20th century, are inscribed in several places including the stone threshold.

A small bathroom compartment has been formed using light-weight partitions. The attached kiln is divided into three small rooms by similar light-weight partitions and has painted exposed stonework and roughly chamfered roof purlins. The lower floor of the kiln is accessed externally through the attached lean-to and has a north opening with a large, crude stone lintel. The interior displays exposed rubble walls with lime mortar pointing. The south wall comprises rectangular slates laid in semi-regular courses incorporating the wrought iron surrounds of the fire hole that heated the floor above. The ceiling is formed of stone slabs spanning the width, with fragments of perforated kiln floor remaining. The attached lean-to contains a rubble cross wall dividing the space into two sections and has a replacement roof structure of sawn timbers.

A stone slab bench is set against the gable, and a mill stone is reset into the ground. At the south-east corner is a short section of attached wall, a raised plinth and stone steps incorporating a mill stone. At the north-east corner, stone steps lead to the lower floor of the kiln.