H.M. Factory, Gretna, Site 3: Eastriggs

Date 12 May 2022

Event ID 1154940

Category Recording

Type Field Visit

Permalink http://canmore.org.uk/event/1154940

Eastriggs Factory and Depot, Dumfries and Galloway

Canmore ID 373534

Site Number NY26NE 139

NGR NY 25095 65037 (centred)

This building is situated in dense deciduous scrub woodland 10m NNE of Explosives Magazine R11 (NY26NW 46.12). It is rectangular on plan and measures about 160m from WNW to ESE by 20m transversely over concrete walls 0.4m in thickness and up to 1.4m in height. A rubble-filled hollow enclosed within its SSW wall runs the full length of the building. To the NNE of this feature are the foundations of two smaller separate buildings which are also enclosed within the main structure. These are separated by a 22m gap containing only drifts of grass- and tree-grown rubble. Each of these buildings is rectangular on plan and measures about 67m in length and 20m in width. The most conspicuous feature of the whole complex are the remains of four brick-built chimneys and their fanhouses (from W to E: NY25032 65035, NY25090 65021, NY25122 65012, NY25151 65004) attached to the SSW of the enclosing building, with one pair attached to each of the smaller buildings. The most westerly chimney and its fanhouse is the best preserved. It measures about 10m from WNW to ESE by 7.5m transversely and now rises about 3m in height. It comprises two elements: on the E there are the remains of a large brick-built flue with a reinforced concrete arched roof leading into the chimney’s base; to its W are the foundations of a small rectangular building with a broad circular aperture in the NNE wall close to the building’s NE corner. This aperture measures about 1.5m in diameter. The building also contains a concrete plinth for an engine. Each of the smaller independent buildings enclosed within the larger structure contain two groups of dwarf walls which are arranged in pairs 0.35m apart. These walls measure 7.0m from NNE to SSW, 0.55m in thickness and at least 0.6m in height. Plinths, possibly for machinery, are situated at the W end of the ESE building, but the evidence does not survive to indicate whether similar plinths were provided for its WNW counterpart. The remains of a narrow-gauge railway within the overall structure runs to the N of each of these buildings. A low, grass-grown platform at least 2m in width and 0.4m in height, is situated two metres to its N. This extends along the full length of the overall building, but the space between it and the outer wall is filled with rubble.

This building is identified as a Boiler House on the plan of, and in test referring to, the works (MMW 1919, plan, 166-7) given in the report by the Ministry of Munitions of War outlining the processes involved in the manufacture of cordite propellant during the First World War at H.M. Factory, Gretna (Site 3). Coal was delivered to the complex by the standard gauge railway running to its E and entered the Boiler House by a series of conveyors situated above a battery of coal bunkers on the N side of the building. This Coal Bunker House was partly founded on the low, grass-grown platform described above. The space between it and the overall building was also included in the Coal Bunker House and was where the machinery was situated that lifted the coal from an individual bunker into its designated boiler. Each boiler rested on a pair of dwarf walls and there were sixteen boilers in each of the two buildings contained within the overall structure. These were divided into two equal groups, each group being surrounded and confined by brick walls almost to their top. The narrow-gauge railway line between the Coal Bunker House and the boilers removed the ash. The report also indicates that the steam generated in the Boiler House was conveyed to the Acids Section (NY26SW 38), the Nitro-cotton Plant (NY26NE 140), the Nitro-cotton Drying Houses (NY26NE 146), also heating all the buildings in these areas. In addition, the heat was also used to warm the acid pipelines and storage tanks during cold weather. The report also explains that the complex was covered with corrugated iron sheeting and the roof was provided with skylights. An undated plan (SUPP 10-39) held in the National Archives at Kew shows the division between the Coal Bunker House and the Boiler House, with the conveyor running down to the tippler (NY 25205 65023) situated over the main railway line. It also shows that the Boiler House was originally equipped with five chimneys, but when the building was reconfigured (see below), one was lost (NY 25061 65029). Blueprints (SUPP 10-24, 3135; SUPP 10-31, 4383, 4385) and ground-based, con-temporary official photographs taken during and after construction (Pearson Collection, 105; MUN 5-297 pt1, 140; MUN 5-297 pt2, 161; MUN 5-297 pt1, 206; MUN 5-297 pt3, 352, 474A; MUN 5-297 pt5, 689-90, 717) also held at Kew, illustrate the character of the complex. The lower section of the Coal Bunker House was a steel-framed, brick-panelled structure which supported a cabin along its full length. This had a ridged roof, skylights and a window in the WNW gable end. The two buildings within the complex were single storey, steel-framed structures with ridged roofs capped by vents running their full length. Their roofs extended to the SSW where the heat exchangers were situated in the space between the boilers and the chimney bases. The W gable of the WNW building had four windows below which there were sliding doors, but the E gable was brick-built and it had four windows above a single doorway which was adjacent to the NE corner. Both buildings were entirely covered with black fire-retardant paint, and were also linked by a low single storey building on the SSE of the gap which contained a series of pumps. This low building had a doorway flanked by windows in the SSW elevation. The fanhouses attached to the chimney bases may have initially been provided with roofs that sloped downwards from ESE to WNW. A capped vent was situated close to their upper edges. The slender chimneys were fabricated of steel and expanded at their feet. However, a series of photographs (MUN 5-297 pt5, 689-90, 717) indicates that the two buildings within the overall complex were reconfigured in about 1917-18. The boilers were originally surrounded and confined by brick walls almost to their top, these walls were now extended upwards to the eaves of the two steel-framed corrugated buildings. These photographs do not show the Coal Bunker House and it is unclear how fuel was delivered to the boilers. The pumps may have been introduced into the two separate buildings because the earlier machinery had been removed leaving a space between them. The roofs of the fanhouses were also reconfigured to slope downwards from NNE to SSW. This remodelling meant that the two buildings were now completely independent boiler houses.

This building fell into lot 508, which was offered for sale by auction on 22-5 July 1924 (HM Treasury 1924, 101, item 1), when the lot was partly purchased by J.M. Temple, Blackhills, Eastriggs and partly by Messrs James Jackson & Co Ltd, St Vincent Street, Glasgow (Carlisle City Archives, DX 2040/3). The catalogue adds that the Boiler House was 7.6m in height. After its removal from the site, only the foundations were left and these are readily visible on an aerial photograph (M124/13 04117) flown on 19 August 1940.

Visited by HES Heritage Recording (MMD and ATW), 12 May 2022.