Restoring the Elsecar Newcomen Engine—High Ideals, Deep Mysteries

The International Journal for the History of Engineering & Technology ISSN: 1758-1206 (Print) 1758-1214 (Online) Journal homepage: http://www.tandfonline.com/loi/yhet20 Restoring the Elsecar Newcomen Engine—High Ideals, Deep Mysteries Geoff Wallis To cite this article: Geoff Wallis (2017) Restoring the Elsecar Newcomen Engine—High Ideals, Deep Mysteries, The International Journal for the History of Engineering & Technology, 87:2, 154-164, DOI: 10.1080/17581206.2018.1462629 To link to this article: https://doi.org/10.1080/17581206.2018.1462629 Published online: 25 Jun 2018. Submit your article to this journal Article views: 27 View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=yhet20 INT. J. FOR THE HISTORY OF ENG. & TECH., Vol. 87 No. 2, July 2017, 154–164 Restoring the Elsecar Newcomen Engine—High Ideals, Deep Mysteries Geoff Wallis Newcomen Society, London, UK Elsecar is an important industrial area, once the powerhouse of the Fitzwilliam dynasty of industrialists. Much of historic interest survives, including extensive remains of its famous ironworks, mid nineteenth century workshops and the unique Newcomen Beam Engine plus its mine-shaft. After decades of National Coal Board (NCB) ownership and an uncertain future, the site was taken over in 1988 by Barnsley Metropolitan Council, who started an ambitious programme of development at the Elsecar Heritage Centre. In 2009 focus turned to the conservation of the engine and funding was obtained from the Heritage Lottery Fund, English Heritage and the Council to carry out the work, that culminated in an official opening in November 2014. Although much modified over its working life, this engine is the only atmospheric beam engine in the world that remains virtually complete on its original site and over its mine-shaft. It is therefore of international importance, recognized by its Scheduled Monument status. Conservation of the site required adoption of the highest standards. This paper describes the extensive preliminary surveys, including under-water investigation of the flooded mine-shaft, the ethical dilemmas of conservation, and the challenges of interpreting a unique historic site for visitors, especially the difficulty of providing access to a cramped three-storey industrial building. The engine house and environs were restored and reinterpreted in 2009–2014. On a project of international importance high ideals were adopted but some deep mysteries remain. Elsecar, Newcomen beam engine, Earl Fitzwilliam, Arthur Shaw, cracked cylinder, A. K. Clayton, shaft KEYWORDS 1. History 1.1. Construction and Working Life A colliery was started at Elsecar Green by Richard Bingley in 1750 and taken over two years later by the second Marquis of Rockingham. At this time the colliery had eight © The Newcomen Society for the Study of the History of Engineering & Technology 2018 DOI 10.1080/17581206.2018.1462629 RESTORING THE ELSECAR NEWCOMEN ENGINE 155 pits, and a horse-powered winding gin was used to bring up the coals from the Barnsley Coal Seam around 50 ft from the surface. The 4th Earl Fitzwilliam inherited the estate in 1782 and put in hand the development of both the ironworks and the colliery. At Elsecar, the Barnsley ‘hard coal’ was available in a 9ft thick seam, ideal for making coke for blast furnaces1 so a second colliery, the Elsecar New Colliery was developed between 1794 and 95 to the north east of the Old Colliery, served by the Elsecar branch of the Deurne & Dove Canal, which ran alongside the site. The canal greatly assisted shipment of coal from the colliery. The Steward of the Earl’s household records payments made for the shaft, engine and house.2 At the start of shaft-excavation on 5th July 1794 a payment was made for ‘sod ale, earnest for the sinkers, and ale for removing the gin and setting it up at the engine pit’ A horse-gin was used for raising spoil and lowering materials in the shaft during the excavation. Payments were made to Michael Hague, Michael Hague Jnr. and Francis Hardy, mason. Michael Hague, the Manager of Elsecar Colliery, lived in a house nearby. He supervised a small team to sink the shaft. Hardy laid the brick lining, whose bricks were all wedgeshaped so as to form a ring that stays in place without any mortar. The shaft was dug down whilst the bricks were built up in sections about three feet high. As each lift of brickwork reached the section above it would have been difficult to insert the last brick, so a slip-brick was used, held in place with an oak wedge, some of which can still be seen. The brick lining extends down to 50 ft. below which the shaft was blasted out of rock with gunpowder, dressed manually, and left unlined. At the bottom of the shaft the sump from which the pump would draw was lined with bricks to protect against erosion at an additional cost of £1 17s 8d. The shaft ran with water and conditions for the labourers must have been both unpleasant and dangerous. They were issued with flannel suits because of the wet conditions, and took five months to reach coal, a rate of about 5ft excavated each week. Seven payments made to the shaft-sinking gang totalled about £175. Around the same time a payment of £279 was made to a Sheffield supplier, John Darwin & Co, for a ‘steam pan’ (wrought iron boiler) for the new engine, so the boiler alone cost far more than sinking the shaft. The team appear to have provided good value for the Earl, and records show that on completion in December 1794 payments were made for a feast and ‘an entertainment for the Masons’. Their New Engine Shaft remains intact after two centuries of use, neglect and continuous erosion by running water, a tribute to their expertise. The Engine House was constructed by the local mason Hardy using locally sourced brick and stone. Records show that work started in October 1794 and was completed a year later, not in 1787 as incised on the lintel over the door. The mystery of the origin of this date is unsolved. Responsibility for constructing the ‘fire engine’ was entrusted to John Bargh, an engineer living near Chesterfield. He obtained estimates for the components, certified them on delivery, erected them, and probably commissioned the Engine himself helped by a small team. Timber for the rocking beam was felled in the nearby Elsecar woods and shaped for use during the autumn of 1794. The metal parts, weighing 16 ½ tonnes in total, were supplied by Longden Chambers and Newton, John Darwin & Co. and the Sheffield Park Ironworks for a total cost of £1,061 8s 11p. 156 GEOFF WALLIS The ‘crab’ (manual winch) still extant on the bob gallery of the Engine house may be the original used to erect the components, in which case it will be the oldest metalwork on the site. Timber beams built into the walls at high level are suitably placed to hoist the heaviest components. One beam still carries a pulley over which a rope or chain may have run from the crab for hoisting light loads, perhaps the cast iron ‘junk ring’ which secured packings to seal the steam cylinder. The ‘Fire Engine’ was set to work pumping out the water in July or August 1795 allowing coal to be mined at greater depths in the dipping 9 foot thick Barnsley Seam. Shortly after the pit was completed a ‘steam whimsey’ was installed for raising the coal. Based on flow measurements recorded two years later A K Clayton calculated that the Engine would have pumped for about ten hours per day if running continuously.3 Payments to one engine minder were made in September 1795, but by November a second minder was being paid, so the Engine may have been working for longer hours. 1.2. Nineteenth Century Bargh was called back in 1799 to repair the lower clack (valve) in the pump, which had broken. Then in 1801 the Butterley Ironworks supplied a new 48 inch diameter cylinder to replace the 42 inch cylinder, and the Coalbrookdale Company supplied three new pumps to provide more pumping capacity. By 1811 the original timber beam was in need of replacement having served for seventeen years. The new beam appears to have lasted for twenty-five years for Clayton in his paper on the Engine4 records that in July 1836 Benjam Biram reported that the beam was cracked and that the pumps were corroded and needed renewal. Messrs Graham of Milton Ironworks quickly provided an estimate of £385 for a cast iron beam, parallel motion, piston and 30 yards 9 inches of 21-inch cast iron pipes including a working barrel. These items are apparently referred to in the Wentworth Woodhouse Muniment as the lengths of the pipes match the depth of the shaft, and the bore of the extant rising is as stated in the estimate, so it seems likely that the major engine parts surviving on site date from 1836. The cast iron frame supporting the two valve arbors (horizontal shafts) is a mystery. A Newcomen engine requires two arbors, one to operate the steam valve and a second to control the injection-water valve. The extant frame carries bearings for a third arbor, typical of Watt separate condenser engines, and its top transom is broken, so it is possible the frame was reused from another engine. Its origin and the date it was fitted are unknown. At some stage during the working life of the engine the cast iron pump stack, or rising main, appears to have moved. One of the wrought iron pump-rods that hung from the rocking beam had been cranked to an offset of about 6 inches to accommodate movement of the top end of the main, a feature that is shown on Clarence O Becker’s drawing believed to date from the early 20th century. Timber clamps around the main wedging against the stagings in the shaft were also added apparently to stabilize it. The Engine continued to pump throughout the nineteenth century but no record of its operation or maintenance have been found. RESTORING THE ELSECAR NEWCOMEN ENGINE 157 1.3. Twentieth Century Electric pumps were installed in the elliptic shaft to the south of the Engine (Ladder) Shaft in 1923 and the Engine was retired from use. At this time, it was reported to be running at 6 strokes per minute,5 less than half its original rate of pumping. However, it worked again for about 6 months from January 1928 when the electric pumps failed. It is probable that at this time the electrically powered Sirocco fan was installed to improve up-cast ventilation in the shaft. The machinery still exists complete, but the fan itself is unpainted and in poor condition. The Newcomen Society visited Elsecar on 11th June 1931 and again on a summer tour on 1950. In 1951 the Engine was steamed again for a Shell ‘Best in Modern Technology’ film series under the guidance of Sir Arthur Elton. The NCB took over the Earl’s workshops in 1947 following the nationalisation of the collieries. It was probably during this period that the timber pump rod was cut and a steel frame with cast iron disc-weights was hung from the outdoor end of the beam to counter-balance the weight of the steam piston. This would have caused the Engine to rest ‘outdoors’ (with pump-rod end of the rocking beam down) allowing the Engine to be operated by steam, but would not have provided sufficient resistance to withstand the large forces generated by steam condensing the cylinder. The Engine could not therefore have been operated on steam safely, which may have contributed to an unexplained incident. 1.4. The mystery of the Cracked Cylinder In 1953 the NCB steamed the engine in preparation for a visit of the Newcomen Society, although no record of a visit at that date has been found in the Society’s archive. At that time Mr Arthur Shaw of the NCB Elsecar workshops was visiting the engine. It had been started but would not run properly, apparently due to problems with the steam supply and the water seal the top of the piston. The engine was stationary but Shaw describes what happened next: The engine came in once—with a heavy ‘bang’,—then a second time, even more noisily and heavily, shaking plaster down,—finally a third time ‘with an almighty bang with plaster down, bricks dislodged, plaster down, the building rocking and the sound of metallic fracture. The engine then stopped’.6 This caused Mr Shaw and an apprentice in the house to ‘fly for their lives.’ It was assumed that the bottom of the cylinder was cracked on this occasion, but this has been disputed by John Crompton and Jim Mitchell, who point out that the indoor catch-wings arrest indoor movement some 500 mm before the piston strikes the false bottom inside the cylinder that had been fitted before 1918 as it appears on a drawing of that date. He asserts that the insert ‘was there to blank off the cracks in the cylinder bottom and allow the engine to run without dismantling it to replace the bottom’.7 Consideration of what may have caused the engine to act on its own may, however, lead to a different conclusion. During the recent restoration no damage to the insert nor the underside of the piston were found, and measurements confirm that the piston could not have impacted, so how could the damage have occurred? 158 GEOFF WALLIS In early atmospheric engines the condensate drains from the cylinder via an eduction pipe whose lower end is open, sited well below the cylinder and restricted to resist the vacuum’s tendency to draw up water during the ‘indoor’ or ‘power’ stroke.8 In normal circumstances therefore the engine is self-draining. At Elsecar the condensate passes via a clack valve into a covered hot-well immediately below the cylinder, which is drained by a pipe running outside the building. This pipe was cut, probably when the concrete collar was constructed around the top of the shaft, and is likely to have been blocked. Large quantities of water pass into the hot-well from steam condensing during warming or blowing through, from leakage of sealing water past the piston and possible leakage through the injection water valve. In the absence of the original header tank, injection water was probably provided by a water main at higher pressure than would have been supplied by the header tank, causing leakage past the injection valve. Additionally, being at rest with the piston at the top of its stroke, the injection water valve may have opened allowing copious quantities of cold water to flood into the cylinder. Whether from leakage or an open valve, the hot-well, overflow pipe, and the bottom of the cylinder filled to a level at which any stroke would cause a hydraulic lock. If a vacuum then formed the piston would strike the false bottom and the shock would be transmitted to the cylinder base. The engine-man was outside the house at the time, so why might the engine have moved on its own? Experience operating the full-scale replica Newcomen engine at the Black Country Living Museum9 has demonstrated that an atmospheric engine will act erratically if there is significant leakage around the piston allowing cold water to pass the junk-ring packings into the steam space below. At that time of the incident the engine was supplied with steam by the workshop’s Lancashire boiler via the receiver still in place to the north of the engine-house. The boiler is likely to have been operating at pressures far higher than the 1–2 p.s.i. required by an atmospheric engine and even if fired sparingly it would have been difficult to restrict the pressure to this level. The cylinder would therefore have become over-charged when supplied with relatively high-pressure steam. Steam would have vented around the piston, dislodged the packings and may have allowed cool water to cascade into the cylinder condensing the steam. With very little outdoor weight on the rocking beam the piston would have descended fast, impacting the water. The steam valve may then have been opened by its linkages, or would have remained open if warming through. A second charge of pressurised steam would then replenish the space under the piston forcing it upwards, being condensed again by cool water leaking past the piston, or injection water admitted by the valve that would have opened at the top of the stroke, causing the second ‘indoor’ stroke. Why would the third stroke be even more violent, as reported? By now more condensate had collected in the bottom of the cylinder and more packing may have been shaken or blown from the piston improving the drenching of the steam. It is also possible that the pressure of incoming steam or shaking of the engine may have knocked the steam valve closed which would have improved the vacuum but then stopped the engine after its final indoor stroke. The cast iron insert is deeper on its front side so it is likely that the impact would be greater on this side. This matches the configuration of the present crack that runs around 70% of the circumference on the south side. The conclusion should be drawn that the cylinder base was cracked in 1953 as reported, not during its service life. This would explain why banding, the cheapest and most RESTORING THE ELSECAR NEWCOMEN ENGINE 159 effective form of repair, was never carried out. It is therefore likely that the false bottom was inserted in the nineteenth century during the widespread endeavours to improve the efficiency of atmospheric engines, not as a means of sealing the cracks. It seems that the decision was made at this time never to steam the Engine again, and the Lancashire boiler was removed in 1954. It is perhaps not surprising that the event was not officially recorded, and that new timber stops of considerable height, which survive today, were fitted onto the indoor spring beams. We owe a debt of gratitude to Arthur Shaw for recognizing the importance of this story and for recording it in such clear detail. The accident demonstrates well the risks of experimenting with an historic engine, and the value of working replicas. 1.5. Recent Decades In June 1973 the engine was scheduled as an Ancient Monument and limited refurbishment, constrained by a lack of funding, was carried out by the NCB in 1981/2. This was led by Mr Peter Clayton, NCB South Yorkshire Area Test Engineer, who recorded the work in detail.10 Over twelve days valves, linkages and bearings generally were dismantled cleaned, lubricated and reassembled. Metal parts were cleaned and protected with paint or anti-rust coating,11 two tons of debris, mostly ash and bricks, were excavated from the basement, the cast iron junk-ring atop the piston lifted and wet, rotten spun yarn packing removed. The boiler feed pump was found to be badly corroded, buried in two feet of mud, its shaft bent, and support beams broken, creating speculation that it may have been implicated in the 1953 accident. It was cleaned, painted and placed in the corner of the house where it still stands. Reference is made in the notes to a ‘condenser pump’ with piston. This is assumed to refer to the header tank supply pump in the pit which no longer has its piston, a loss which has not been explained. The engine was moved at this time, which bent the parallel motion bars because the pump-rod bearings were seized. The author’s company Dorothea Restorations Ltd straightened the rods in 1996–7 and reported that the rocking beam could then be moved easily.12 The Company proposed a programme of repairs, painting and artificial activation of the engine but this was not carried out. The crack around the bottom of the cylinder was metal-stitched by Cast Metal Repairs Limited of Wakefield in January 1984. Later that year the four-inch diameter lead injection water pipe, the bronze junk ring bolts and possibly other parts were stolen. NCB engineers moved the beam annually by hand until 1987, but as collieries began to close the demand for the workshop facilities declined leading to the closure of the Elsecar facilities. Barnsley MBC purchased the Engine and workshops in 1988, the latter subsequently being restored and opened to the public as the Elsecar Heritage Centre. The electric pumps were switched off in 1996 and removed the following year, although their control gear was left in place in the pump house immediately to the west of the Newcomen Engine House, where it still survives. Power to the site was disconnected in 1998 after which no work is known to have been carried out below ground other than regular dipping to establish the water level in the shaft. 160 GEOFF WALLIS 2. The Shaft—a 100 Feet Deep Mystery During the shaft’s service life an emergency escape route was created by stabilizing the entrance to the Barnsley Seam with a concrete lining and construction of eight lifts of steel-framed platforms and steel ladders with cast iron treads. Materials and construction suggest that these may date from the early/mid twentieth century, perhaps constructed at the same time as the 4 ft deep concrete collar that stabilizes the top of the shaft.13 At some time before the electric pumps were turned off in 1996 the windbore (the lowest section of the rising main) and two clack-box doors were hauled to the surface, possibly to reduce the weight of the pump-stack, or as an endeavour to retrieve as much historic material as possible before the shaft was allowed to flood. No record of any shaft work has been found in the NCB or Barnsley MBC archives. The engine, house and shaft are all protected by Scheduled Monument legislation, but the shaft had received little attention over the years having been flooded to within 8 m of the surface since 1966, and, being a confined space below ground, was difficult and potentially costly to access. The original brick lining and 22 inch (560 mm) diameter cast iron rising-main were known to survive, but research yielded no archival information about the structures below water. It was therefore imperative to investigate the shaft and determine its conservation needs. In 1993 the shaft was reported to be 45 m (148 feet) deep and flooded to 20 m (66 feet) below the surface.14 The steel platforms were in poor condition and said to be supporting the rising main by means of timber blocks described as ‘waterlogged and rotting in part’. In a further inspection in 1997 Dorothea Restorations noted that the windbore had been removed and that: The rising main does not extend into the water of the sump, reflected daylight being visible at the bottom of the bore.’ ‘It is possible to rock the head of the rising main to and fro from the top landing indicating that it is not braced to, nor supported by any of the upper landings.15 It became clear that the historically important eighteenth-century shaft and its early nineteenth century cast iron main had shown signs of distress in the past, and may need to be stabilized. It was therefore imperative to find out whether the shaft was still open, what it contained and its condition. In particular it would be important to know whether the rising main was stable. Initial investigations above water level revealed the top two ladders to be severely rusted and have cracked cast iron treads. The top ladder was removed and stored in the adjoining electric pump-house, the stagings cleansed, and the thickness of the rising-main wall measured by drilling a small hole. It had lost a modest amount of probable original section, but seemed otherwise structurally adequate. The brick lining, made of wedgeshaped bricks fitted without mortar, was generally intact, but bulged in two places. The first underwater investigations were by side-scanning sonar lowered on a manual winch from a scaffolding platform built over the shaft. This showed that the shaft was open to the bottom, confirmed the depth, proved that the stagings and ladders were all in place, and that the upper part of the rising main is leaning, confirming that it had moved northwards about 9 inches (250 mm).16 Scanning the bore of the rising main showed it to be filled with rust debris to a level below the lower clack box. A visual inspection was then carried by a remotely operated vehicle (ROV) in crystal clear water. Clearly visible were each platform and ladder, the heavily corroded cast iron RESTORING THE ELSECAR NEWCOMEN ENGINE 161 main, the walls of the shaft, and the clack boxes from which the covers on the surface had been taken.17 At Barnsley Seam level the concrete lined entrance was viewed but was obstructed by a thin plastic pipe preventing the ROV from entering without risk of its umbilical snagging. At this level a steel walkway fills much of the shaft, built around the rising main which could be seen extending below. Repeated attempts to penetrate gaps failed, and the ROV could not access the bottom of the shaft to view the structure assumed to be supporting the main, none having been found at higher level. Data provided by the sonar and ROV surveys enabled scale drawings to be prepared, and provided enough certainty over the condition of the shaft’s structures to allow a diving inspection. Access to the water was provided by a scaffolding suspended from the surface, and controlled by a mobile dive-control station with continuous communication between dive-master and the diver. Video monitoring of the operation from the surface was achieved via the diver’s helmet camera. Working in good visibility the diver found the pump-stack, stagings and ladders to be heavily corroded but apparently stable. The plastic pipe obstruction at the entrance to the Barnsley Seam was removed and the diver walked a short distance into the access passage proving that it was still open. A future ROV inspection of the seam is thus possible. A close inspection of the area where the rising main passed downwards through the bottom staging revealed a possible access route into the bottom of the shaft, but this proved to be obstructed by a strut and too dangerous to negotiate in full diving gear, so the diver was withdrawn. It was decided instead to probe the depths from the staging using a 2 m wooden rod with the helmet camera taped to its lower end. This revealed a solid, regular surface, 1–2 metres below the staging, covered with a thin layer of lightweight fine debris. The rising main could not be viewed closely but no structure of sufficient size to support its estimated 20T weight was seen.18 Uncertainty therefore remains as to how the rising main is supported. It is known that the lower half is leaning 250–300 mm but the upper section is vertical. It was stabilized by pairs of timber blocks resting on stagings at four levels but that these are unlikely to be carrying weight now. A hard, uniform surface exists just below the bottom (Barnsley Seam) staging and no other support structure is visible. It has therefore been assumed that the bottom of the shaft has been filled with concrete to support the rising main which was known to be unstable. The windbore may have been removed to allow concrete to be tipped into the rising main from the top, which would have been the easiest way of carrying out the stabilization work. Various options for stabilizing the rising main were considered, including ‘soft filling’ the shaft, which would be irreversible, or suspending the structure from the top, which risked putting the castings into tension and cracking them if the shaft settled. It was therefore decided that the best conservation option was to monitor the position of the main to gather more information on its long-term stability and not attempt pre-emptive stabilization until the need is proved. 3. Conservation of the Engine and House—High Ideals The restoration project was overseen by a Partnership Board19 who decided at an early stage that the site would be conserved as found with minimal alteration and modern intrusions. Thus twentieth century alterations were retained, including steel pipe-work, 162 GEOFF WALLIS some incomplete, and the feed-water pump was left in its relocated position. Missing parts were not generally renewed, except for the injection water valve’s lead pipe and the bolts securing the junk-ring to the piston as details were known and they helped visitors to understand the engine. Detailed surveys of the house, chimney base, engine, shaft and immediate environs were carried out in 201120 from which contract documents were prepared and works tendered competitively. Where photographs or other primary evidence showed structures to have been replicated incorrectly in the past they were reinstated to an earlier appearance. Thus the head-frame that dated from the twentieth century was reconstructed to an earlier design from photographs. A determination not to replace steep ladders with new staircases in the house meant that visitor numbers have to be restricted, and as the engine would move with visitors in close proximity, parties would have to be supervised. However, guiding and restricting visitor-numbers allowed a reduction in the level of guarding and lighting, and elimination of interpretation panels from the house. Lighting was limited to dimmable LED’s above stairs and walkways and new guards were installed around the rocking beam and over the open cylinder only. The guards were specially-made detachable frames hooked or clamped on to avoid drilled fixings and were laced with rope infill. Electrical sockets for servicing each floor and their distribution cabinet were hidden in cupboards, and behind a door. The risk of fire in such an important building justified a modern detection system with extinguishers and a detector head which proved to be the most visible of the few additions to the house. The survey of the engine revealed that the piston, cylinder, pipe-work, valves and valve-gear were in relatively sound condition with some historic wear and damage. Metallurgical tests on the metal stitches strengthening the crack around the cylinder base proved the material to be mild steel, offering minimal risk of galvanic corrosion.21 Severe decay in the two softwood beams supporting the rocking beam had caused one bearing to subside 50 mm causing both parallel link-motions to twist and seize, possibly bending their slender wrought iron rods. Dorothea Restorations jacked the subsided trunnion-bearing back to its correct level and supported it on temporary timber blocks. All bearings were dismantled, inspected, cleaned, greased and re-erected without renewal and trials carried out in June 2013. The contractors were delighted to discover that simply standing on one end of the beam caused it to stroke silently and smoothly, its first stroke in more than two decades. The whole of the bob platform was subsequently renewed, new beams being scarphed to sound ones inside the house. Paint at numerous locations was analysed and its dozen strata found to be relatively uniform.22 Metalwork was originally coated with several coats of black lead paint, described as having the ‘appearance and texture of blacking or Zebo’. This had been over-coated with red oxide (or possibly minimum orange), and grey or blue/grey. Later coats are blue, then light green, overlaid by cream which was the finish coat at the time. The joinery of the house carries a similar sequence, with more numerous later coats of green. The antiquity of the historic coatings was uncertain, so it was decided that all extant paint would be retained, regardless of its condition. The timberwork of the house was re-painted green as found, and the engine coatings over-painted with single-pack alkyd oil paint, sheen finish. The colour red oxide was chosen to match two earlier finish coats, and new components such as guards were painted grey to distinguish them from RESTORING THE ELSECAR NEWCOMEN ENGINE 163 the historic structure. Formerly polished metal-work was de-rusted and coated with two applications of microcrystalline wax. Impacts had cracked the indoor wrought iron catch-wing and the outdoor end of the cast iron beam, which had been repaired by plating. The outdoor repair was dismantled, cleaned, painted and reassembled, whilst the indoor catch-wing was load-tested to verify that the cracked end would adequately support its own weight, avoiding the need for an intrusive repair. 4. Animating the Engine An important objective of the restoration project was to activate the Engine to enable visitors to understand more easily the way it performed its role. A number of previous reports had assessed the feasibility and risks of operating the engine, one suggesting that it should be re-steamed. However, this was discounted at an early stage because of the difficulty in providing a sufficiently large balancing load, the degree of intrusion that would be required to restore or renew historic parts, conservation concerns over introducing moisture to the inside of historic metal components, and the costs of capital works, operation and maintenance.23 The brief adopted was that equipment to animate the engine would have to be automatic, capable of remote control by the guide, fail-safe and not put the historic components at risk in case of malfunction or derangement. New equipment would have to be sited discreetly, not require any changes to be made to the historic fabric, and be removable without trace. The least intrusive option was to place a small hydraulic ram inside the empty cylinder of the water pump in the basement acting on the plug-rod. This could only work safely retracting, drawing the indoor end of the rocking beam downwards, so a replica pump-rod was constructed in steel to match the former timber rod, and filled with lead shot to balance the beam heavy outdoors. One of the original forked wrought-iron rods was reconnected so that it again entered the top if the rising main from which it once pumped. The hydraulic power unit was sited in the nearby electric pump-house to isolate its noise and for ease of access. Its operation was controlled by a small programmable logic circuit with proximity switches sited in the basement. The drive operates the engine at half its original speed and mimics the action of operation under steam in which the power or ‘indoor’ stroke is faster than the return stroke. In case of failure the hydraulic equipment stops the engine and holds it secure until manually parked and the system reset.24 The unveiling and opening of the newly restored site took place on 21st November 2014 with a spectacular light-show in which the engine house was bathed in coloured light and its indoor moving parts projected onto the outside walls. A reception celebrated the achievement was attended by many Newcomen Society members. The Newcomen Society President Geoff Wallis and Vice President Michael Grace met the Society’s patron HRH the Duke of Gloucester on March 11th 2014, acquainted him with the restoration of the Elsecar Engine and presented to him copies of section drawings of the engine and shaft. HRH Prince Edward subsequently visited the site to view the restored engine, which is now open to the public and demonstrated regularly. 164 GEOFF WALLIS Notes 1. A. K. Clayton, ‘Newcomen Type Engine at Elsecar West Riding’ (Read at the Institution of Mechanical Engineers, May 1963 (1964). 2. Fitzwilliam Wentworth Woodhouse Muniment, Sheffield City Archives. 3. A. K. Clayton, op cit., p. 103. 4. A. K. Clayton, ‘Newcomen type engine at Elsecar west riding,’ Transactions of the Newcomen Society, 35 (1962–3), 97. 5. A. K. Clayton, op cit., Transactions of the Newcomen Society p. 103. 6. Barnsley MBC Archives a/81c/12/9. 7. J. Mitchell, Elsecar Engine Report, Update, 2010, p. 131. 8. L. T. C. Rolt and J. S. Allen, The Steam Engine of Thomas Newcomen (Moorland Publishing, 1977), Diagrams on pp. 37, 41. 9. The Dudley replica engine was restored by the author in 2011–12 and operates frequently. 10. Barnsley MBC Archives, reproduced in Jim Mitchell, Elsecar Engine Report 2010, Update, pp. 133–138. 11. In a private conversation with the Author in September 2011 Peter Clayton stated that the coating was ‘black rust inhibitor recommended by the navy’. 12. Dorothea Restorations Ltd, (1997) Report The Newcomen Engine at Elsecar, p. 13. 13. Stabilization and construction of concrete head frames at Hemingfield and Elsecar Collieries are reported to have been carried out in the 1940’s. 14. Museum of Science and Industry in Manchester (January 1993), Report on the Restoration of the Newcomen Engine at Elsecar, Barnsley. p. 6. 15. Dorothea Restorations Ltd, op cit., pp. 18 & 19. Atlantis Marine Ltd DVD held by Barnsley MBC archives. 17. Atlantis Marine Ltd, ROV Survey Report, 20–21st September 2011, Barnsley MBC archives. 18. Underwater Survey, Elsecar Mineshaft Video, DVD, Commercial Diving & Marine Services. Barnsley MBC archives. Dive carried out 28th March 2013. 19. The Partnership Board comprised representatives from English Heritage (now Historic England), Barnsley Council, the Heritage Lottery Fund, the project architect and engineer, and other stakeholders. The author was appointed Engine Consultant. 20. The project was initiated in 2009 by Lynne Dunning, Group Leader, Arts & Heritage, Barnsley MBC and Dr John Tanner, Project Manager and subsequently delivered by them. 21. Caparo Laboratories, Willenhall, Laboratory Internal memo, (2011), Barnsley Archives. 22. Hirst Conservation Ltd, Results of Architectural Paint Research to the Beam engine & Engine house, Elsecar Heritage Centre, (November 2011). 23. Dorothea Restorations Ltd, Elsecar Heritage Centre Newcomen Engine & Shaft Conservation Study (November 2011), p. 26. 24. Restoration of the engine and provision of a new cover to the shaft were undertaken by Lost Art Ltd of Wigan, Lancashire. 16. Notes on Contributor Geoff Wallis is a Chartered Engineer, who trained as a mechanical engineer in the aerospace industry before taking up a career in conservation. He was managing director of Dorothea Restorations Ltd for three decades specializing in repairs to historic metalwork and machinery before becoming a consultant. Geoff is a long-standing Member of the Newcomen Society and its Past President. He is a member of the Bristol Industrial Archaeological Society and its current President. Geoff has contributed to a number of books and journals and lectures widely on the conservation of historic metalwork and machinery. Correspondence to: Geoff Wallis. Email: jandgwallis@gmail.com