Lime Kiln 320m North-West of St Peter's Church

Lime kiln, circa 1900, located 320 metres north-west of St Peter's Church, Portland.

This lime kiln was constructed and operated by prisoners from the Portland Convict Establishment to process limestone from the surrounding quarries. It was built within an enclosed stone dressing yard situated in the disused south-western part of Admiralty Quarry. The kiln is one of at least six individual examples that existed on Portland between 1864 and 1902.

The kiln is built of limestone ashlar with a rubble core and has a distinctive tapering cylindrical form. It survives to approximately its full height. On the west and east sides are segmental-headed arched openings with keystones to the two draw holes or 'eyes'. At the rear (north) of the kiln is a segmental-headed outer arch to a stoke hole which retains the cast-iron surround to a fire grate. The interior contains a largely complete single-cell tapering chamber with some rubble in the lower part.

An enhanced bank runs against the kiln with a charging ramp to the right side to facilitate loading of fuel and broken limestone. The charging ramp is roughly rectangular in plan and is battered with a rubble core and facing of coursed rock-faced limestone, though some of the facing on the principal (south) elevation has collapsed. The ramp is keyed into the kiln towards its left-hand end. Three semi-circular arched openings in the south elevation of the ramp probably served for storage and shelter. At the west end is a passageway with segmental-headed archways at either end, providing access to the rear of the kiln.

The kiln was originally sited at the north end of the stone dressing yard, all set within a walled enclosure. Several rectangular single-storey buildings within the yard, associated tramways, and a large proportion of the boundary wall have been demolished since the yard closed. The kiln ceased operation around 1921 when the prison became a Borstal Institution and the quarry and associated masonry works closed.

The surviving kiln represents an important record of both the lime production industry and the significant role of convict labour in Portland's industries during the 19th and early 20th centuries.