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Y Tabernacl
Open Day
21st May, 2008

Yr Hen Danerdy

The Old Tannery in Machynlleth


air photo

Aerial view of Machynlleth with the old tannery building visible towards the top, behind the white-painted Tabernacle. Photo CPAT 03-c-0759

Machynlleth had a long association with the tanning industry which can be documented from the 17th century until the early 20th century, although it is likely to have a much longer tradition. During the 19th century the tanning industry seems to have been centred around Heol Penrallt, and in particular the area known as Maes Glas. It seems likely that the building now known as Yr Hen Danerdy was constructed as a purpose-built tannery in 1819 and remained in operation until the end of the 19th century.

A programme of building recording was undertaken at Yr Hen Danerdy, on behalf of the Machynlleth Tabernacle Trust, with financial support from the Heritage Lottery Fund. The survey was conducted in connection with proposals to convert the building into a new gallery and store for the Museum of Modern Art, which occupies the former Tabernacle chapel immediately to the south of the former tannery.

The Tanning Process

The processing of leather has always been an unpleasant activity, resulting in foul odours and noxious waste, which must have been all too apparent to the inhabitants of many Welsh towns. A number of related trades were involved in the leather industry, with the supply of raw materials, the production of leather, and the manufacture of leather goods.

There were many variations in the process of tanning, depending on the quality of the hides and the intended end product, although the most common procedures are outlined below. The tanning process required a good supply of clean, soft water, and many tanneries were located close to streams and rivers, although in Machynlleth this was not the case and the supply must have been provided by a spring.

The process started with the skinners who provided the cattle hides and sheep or goat skins. Before the actual tannage could begin much had to be done to prepare the hides, starting with washing. Once clean, the hides were usually soaked in large pits containing lime and water, the pits containing the solution in a variety of strengths which depended on how many times it had been previously used; the process took between 7 and 14 days until the hair could be easily removed.


Right: Illustration of a tanner's beam and knives.

The hides then transferred to the 'beam house' to be unhaired, which was done by placing them on a sloping table of wood or iron with a convex section called a 'beam', and scraping them with a special knife. Once the hair had been removed the hides were thrown into cold, soft water before undergoing 'fleshing' to remove any fatty tissue, again using the beam, but with a different tool.

The industry was notorious for the use of animal excreta in solution, although this was mainly for some soft leathers to remove excess lime by soaking them in 'mastering pits'. The use of pigeon or hen dung was known as 'bating', while the use of dog dung was known as 'puering'.

The purpose of tanning is to produce a product which is sufficiently soft, resistant to water, and not liable to decompose. The actual tanning process involved the immersion of hides in pits containing the tanning medium for varying lengths of time, depending on the grade of the leather. The most common tanning medium was produced using large quantities of finely ground, dried oak bark, added to cold water to make liquors of varying strengths. The hides started in the weakest solution, being gradually moved from one pit to the next with the strength gradually increasing. The freshly prepared medium was the strongest and, like the lime solution used earlier, the strength decreased the more the solution was used.

The tanned hides were then washed and scoured before being dried in a controlled atmosphere, normally undertaken in a room with adjustable slatted windows which allowed a good circulation of air without any direct sunlight.

Following the completion of the tanning process the currier was responsible for finishing the leather by softening, colouring and generally refining it to create the intended final product.

The Tanning Industry in Machynlleth

Like most market towns in Wales Machynlleth had a long association with the tanning industry, which can be traced for a period of around 300 years from the earliest known documentary evidence, a reference to tanners in 1610, until the early years of the 20th century. The parish registers of 1782-1792 provide a clear indication of the importance of the industry, recording 15 people engaged in skinning, tanning and currying, with a further 30 saddlers and shoemakers, accounting for 15% of those recorded.

The earliest indication of a tannery in the Maes Glas area comes from a record of rents in the town in 1686/7 which includes an entry on Heol Penrallt for Ismaell Jones, paying 3/6d for 'his house, tanhouse, barne and garden, lands of Cathrin Evans, widow'. In 1763 a summary of rentals for the Wynnstay Estate records a 'house, tanhouse and gardens', owned and occupied by Humphrey David, paying 1/-, which appears next to an entry for Maes Glas.


Right: A contemporary postcard of Machynlleth shows part of the eastern range of the tannery in the bottom right, although sadly most of the building is obscured by the rock outcrop.

The 1861 census records David Evans, a tanner aged 22, as a visitor to Penrallt Street. By 1871 he resided in Penrallt Street near the Skinner's Arms and is described as a tanner and currier, and ten years later a more precise location is given adjacent to the tannery in Wesley Lane, the passage from Heol Penrallt which runs between the former Wesleyan Chapel and the tannery.

The earliest cartographic depiction of the tannery in Maes Glas is the Ordnance Survey 1st edition 1:2,500 map of 1889, surveyed in 1887, which is broadly contemporary with the tenure of David Evans. This shows an L-shaped building partly enclosing a yard area within which five pits are depicted. Another tannery is recorded further to the east, off Brickfield Street.

Building Survey

digital survey

Digital survey of tannery interior. Photo CPAT 2506-082

The detailed building survey was largely completed using digital surveying techniques, with additional detail added by conventional measured survey.

The purpose-built tannery originally consisted of an L-shaped building formed by two ranges. The eastern range measured 24.2m by 8.2m, aligned north to south, and extending as far north as Maes Glas. The northern two thirds of this range was demolished perhaps 40 years ago, although part of the external walling still stands to over 2m in height. The southern range survives intact and measures 16.8m by 6m, aligned east to west along the northern side of a passage leading east from Heol Penrallt. There was an enclosed yard area on the northern side of the building, within which five pits were depicted by the Ordnance Survey in 1889.

The surviving structure has been largely gutted internally, having been used in later years as a store room. There are few internal features which are contemporary with its use as a tannery, although the original trusses and some of the window frames do survive. The internal floor level has been raised, particularly in the southern range, by the deposition of a significant quantity of rubble, probably from the demolition of the eastern range, on top of which is a modern concrete floor. There is also a significant depth of rubble in the yard area.

The building has two storeys and is stone-built. The ground-floor openings all have brick arches, while those on the first floor have timber lintels, with the exception of a window in the west gable. There is a small and unobtrusive date inscription on a quoin at the southern end of the east elevation, which reads 'John Williams 1819', and it seems reasonable to assume that this represents the date of construction.

digital survey

Right: Date inscription 'John Williams 1819'. Photo CPAT 2506-064

The southern range is divided into five bays by three trusses and a partition wall which separates the eastern bay from the rest. The western three bays were originally open at ground- and first-floor level, although the floor has since been removed and replaced in part by a rough platform at the western end. On the ground floor there was a single doorway in the southern wall, which is now blocked, and four matching doorways in the northern wall, opening onto the yard. The stone partition wall originally had a central doorway which was later blocked; presumably at the same time new openings were inserted against the southern wall, through both the partition wall and the west wall of the eastern range.

N elevation

Above: North elevation of the southern range showing louvred windows on the first floor and ground-floor doorways into the tanning area. Photo CPAT


Right: Louvred window in southern elevation of southern range. Photo CPAT 2506.101

The first floor was undoubtedly the drying room, or airing loft, with opposing louvred windows. The louver boards were fitted into the frame by means of a wooden peg in either end which allowed them to pivot.

The three trusses are of simple form but with unusual curved struts between the tie-beam and principal rafters, which support the ridge pole and two purlins on either side. Each truss has two mortices in the underside of the tie-beam which would have held posts. By comparison with the Rhaeadr Tannery, it may be assumed that these supported the tenter rails on which the tanned hides were hung to dry.

The eastern bay clearly had a different function, being separated from the main area by the partition wall. On the ground floor there is a large doorway opening on to the yard with another doorway, now blocked, giving access to the eastern range. The joists for the first floor still survive, with their configuration suggesting that there may originally have been a trap door or stairs in the centre of the room, which was later boarded over. On the first floor there is a single window in the north wall with a blocked central doorway through the partition wall, and an extant doorway leading into the eastern range.


Right: Southern Range Truss 2 viewed from the west. Photo CPAT 2506.002

The surviving southern end of the eastern range appears to have formed a single large room on both ground and first floors. On the ground floor the eastern wall now has a large inserted doorway which has removed any evidence for earlier openings. Doorways in the west wall originally led into the southern range (now blocked) and the south-east corner of the yard, while the southern wall has a single barred window, the original opening for which appears to have been reduced in height.


Eastern Range king-post truss. Photo CPAT 2506.019

There is a single, pegged king-post roof truss with iron straps, which supports the ridge pole and two purlins on either side. The southern gable has six ventilation slots and there is a further single slot in the west wall, which unusually opens into the adjoining southern range rather than the exterior. Their presence indicates that this room was used for storing the oak bark which may have been brought in ready milled, or as bark strips to be dried and milled on site. A doorway in the east wall would have been used for loading the bark from the lane below, while other doorways led to the northern part of the range, the yard with presumed external stairs, and lastly into the southern range.


Internal partition wall in the eastern range exposed following the demolition of the northern section. Photo CPAT 2506.048

Although most of the northern section has been demolished a substantial part of the northern end survives, including a blocked first-floor doorway which would have provided access directly from Maes Glas, the building having been terraced into the slope at this point. The window opening in the partition wall which now forms the northern gable end suggests that the lost portion of the range included a loft space.

Ground Penetrating Radar Survey

A ground penetrating radar (GPR) survey was undertaken by ArchaeoPhysica to investigate the interior of the southern range, with an additional profile across the external yard in an attempt to confirm the location of the pits depicted in 1889.

digital survey

Right: Ground Penetrating Radar Survey inside the southern range. CPAT 2506.068

A recently-excavated test pit inside the southern range, adjacent to the blocked southern door, demonstrated the nature of the upper deposits, comprising a 0.15m-thick concrete slab, on top of a considerable depth of building rubble. The GPR survey demonstrated that the rubble layer is around 0.8m thick, and probably lies directly on the original floor of the tannery at around 0.95m beneath the surface of the concrete. However, in the eastern room of the southern range the original floor appears to have been much higher, possibly just below the concrete.

The survey was very successful in identifying structures relating to the tannery, including two rows of three tanning pits cut into the bedrock, each measuring around 1.8m by 1.5m. Two possible drains were also identified, one of which corresponds to a blocked opening visible in the exterior of the south wall.

digital survey

Above: Ground penetrating radar survey results at around 1.5m below the concrete floor( ArchaeoPhysica)

The single profile across the external yard appeared to confirm the approximate position of the five pits, although the data was not sufficiently clear to provide good definition. However, it did confirm that masonry belonging to the demolished side walls of the northern range survives just beneath the present ground surface, while the interior is likely to be between 0.5m and 1m below the surface. The yard appears to be buried beneath up to 1m of rubble, which also covers the external pits.

The geophysical survey report is available as a downloadable PDF


As we have seen, Machynlleth had a long association with the tanning industry. Although this can be documented from the 17th century until the early 20th century it seems probable that tanning was an activity which goes back to the medieval origins of the town. During the post-medieval period the tanning industry seems to have been centred around Heol Penrallt, and in particular the eastern side of the street, in an area known as Maes Glas, although by the late 19th century there was also a tannery known as Brickfield House further west in the Garsiwn area. As well as tanners, there were a variety of other related trades in this area, including skinning and currying. There is, however, little physical evidence of the industry today, which adds to the significance of Yr Hen Danerdy. The only other indication of the industry is the name of the public house on Heol Penrallt - 'Skinners Arms'.

Although the documentary evidence clearly indicates the presence of tanning in this area from the 17th century it is not possible firmly to associate the industry with this particular site. It seems likely that the building now known as Yr Hen Danerdy was constructed as a purpose-built tannery which may be dated on the evidence of a date stone inscribed 'John Williams 1819', and is consistent with the style of the king-post roof truss in the eastern range.

rhaeadr tannery

Right: Photograph of the Rhaeadr Tannery with tanning pits in the foreground

Although the tannery was small in comparison to others in mid-Wales it was certainly large enough to have processed both cattle hides and sheep skins and appears to have remained in operation until the closing years of the 19th century. During the latter part of its life the tannery was probably run by David Evans. The Brickfield tannery on the western edge of the town remained active into the 20th century, possibly because of its location, with the more central location of Maes Glas eventually proving rather less popular for such a noxious business. During the 20th century the building was for a time used by the Dyfi Valley Lime Company for bagging lime.

Based on the surviving evidence, and through comparison with the contemporary Rhaeadr Tannery, it is possible to give an indication of how the tannery would have operated, although there is insufficient evidence to determine the function of all the rooms within the building. The first stage would have been to soak the hides in pits containing a lime solution, and comparison with Rhaeadr suggests that these may have been some of the external pits in the yard, although one pit may have been reserved for clean water. The unhairing and fleshing operations would have been carried out in the 'beam house', which may have occupied the now demolished section of the eastern range, or possibly either the western end of the southern range or the small room at the eastern end, both of which are roughly equivalent in size to the beam house at Rhaeadr.

ventilation slots

Above: Ventilation slots in the south wall of the bark store. Photo CPAT 2506-063

The tanning medium was a mixture of ground oak bark and water and the ventilation slots on the first floor at the southern end of the eastern range suggest that this is where the bark was stored. There is no evidence for any milling machinery and it is possible that the bark was brought in ready milled. Having been suitably prepared, the hides were then placed in the tanning pits, which are likely to have been the six pits identified by the GPR survey inside the southern range, the hides being moved from one to the next into solutions of increasing strength. The tanned leather was then hung to dry on tenter rails on the first floor of the southern range. The room was well ventilated, with the air flow controlled by adjustable louvred vents. This range is also likely to have been the location of the currier's workshop, where the leather was finished according to its final usage. However, at the time the building was constructed it was illegal to combine the processes of tanning and currying and the latter must therefore have originally been conducted elsewhere.

The tannery would have required significant quantities of clean, soft water, and it has not been possible to confirm a source at Maes Glas, which is some distance from the nearest watercourse. It has been suggested, however, that water may have been provided by a spring on the slopes of Pen-yr-allt. The disposal of waste water would also have posed a problem and must have utilised a drainage system leading onto Heol Penrallt via the passage along the southern wall of the tannery. The GPR survey identified two possible drains beneath the southern range.

The surveys have been undertaken with the aid of a Planning Grant by the Heritage Lottery Fund to enable the Machynlleth Tabernacle Trust to submit a full planning application for the conversion of the building into a new gallery and stores. This is only the first stage in the process and fundraising continues to ensure that the project is successful. For further details about the project and the Museum of Modern Art, follow this link

The full survey report is available as a downloadable PDF

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