MSO7424 - Medieval and post-medieval iron working site and iron hammer mill in Horner Wood (Monument)

The remains of a building associated with an earthen dam over 2 metres high, in Horner Wood. The presence of large quantities of smithing and smelting slag suggest that it is the site of a documented "iron hammer mill" smithing site dating to the late 16th century.

A ruined building and dam were discovered in Horner Wood and surveyed by N. Berry in 1995, who associated the site with the documentary reference to a hammer mill being set up in the parish in the late 16th century by George Hensley from Selworthy. [1] The site formed part of a joint Exmoor National Park Authority and National Trust project on early ironworking sites on Exmoor (site FE96 002). As part of this work, it was visited by Gill Juleff in 1996 who discovered large quantities of smithing slag as well as smelting slag. [2] The site was surveyed at 1:500 scale by staff of RCHME's Exeter Office in 1996 at the request of Exmoor National Park Authority and as part of its East Exmoor Project. The site is centred at SS 8967 4387 on the western side of Horner Water. It lies within dense deciduous woodland, and the building and dam are overgrown. The remains consist of a substantial stone revetted earthen dam, over 2 metres high, running west to east across the valley of Horner Water. Formerly 55 metres long, the central section has now been breached and carried away by flood water, so that only a stub survives on the eastern side of the river, whilst a 27 metres stretch survives on the west. Although now dry, it is clear that this dam was capable of ponding back a very substantial sheet of water which would have occupied the narrow valley floor. To achieve this, the river was diverted into a cutting, some 260 metres long and up to 3 metres deep, which runs along the western side of the valley floor, skirting the dam and building on their western side. Below the dam, on the northern side of its western end, is a rectangular building, measuring 6 metres by 14 metres, surviving as stony banks (0.5 metres high) with coursed wall faces visible in places. The building is two celled, and may have been open fronted on its eastern side. The position of the building strongly suggests that it is associated with the dam, and was involved in the water powered processing of iron; it is almost certain that it is the `iron hammer mill' referred to in the 16th Century. [3-5] Analysis of the charcoal sample indicates large amounts of narrow roundwood, mostly oak with some ash and birch, with less frequent mature wood, probably mostly from coppice and pollards on a 15-30 year cycle. The contemporary environment was probably similar to the present day, with little change in woodland progression. [8,9,11] An accidental drowning occurred "at a certaine Iren mill poonde of water" at "hornewoode" (Horner Wood) on 14 November 1593. Jane Jordaine, the wife of "Iren man" William Jordaine of Luccombe, was washing her muslin clothes on the edge of the pond and was blown in by a gust of wind. The pond was noted to be 10 feet deep and 40 feet wide. It is possible that this is the site of the drowning. [14] No change. The site has display potential and has substantial undisturbed structures and deposits. [15] This record was enhanced as part of the National Record of the Historic Environment to Exmoor National Park Historic Environment Record data transfer project. [16]