What is recorded here

Two small furnace pits sat half a metre apart on the low Johnstown ground, filling with iron slag and charcoal before anyone laid a road above them. They may have belonged to the fourth century BC, though old oak wood can deceive a date. The M4 builders uncovered them in 2002, proving that ordinary-looking soil there still holds the heat of forgotten making.

Situated on an undulating low-lying landscape. Archaeological testing in advance of the M4 Kinnegad to Kilcock motorway identified sub-surface archaeological features. These were set aside for resolution as Johnstown 3, which was resolved (02E1094) in October 2002. Two furnaces (dims 0.37m x 0.32m; D 0.2m: 0.26m x 0.26m; D 0.17m) with similar fills including iron slag and charcoal were cut in the subsoil and placed just 0.5m apart. A sample of oak charcoal from the smaller produced a C14 date of Cal BC 420-230, but the possibility of old wood arises. (O’Hara 2004, 2008) Compiled by: Michael Moore Date of upload: 14 August 2019 O’Hara, R. 2004 Johnstown 3. Bowl furnaces. In I. Bennett (ed.) Excavations 2002: summary accounts of archaeological excavations in Ireland, 416-7, No. 1472. Bray, Wordwell O’Hara in Carlin, N., Clarke, L. and F. Walsh 2008 The Archaeology of Life and Death in the Boyne Floodplain, vol. 2, Johnstown 3. National Roads Authority, Scheme Monographs 2. Dublin

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