May 2013 - Work in Progress

Work has progressed at speed in all areas of the site during the months of April and May. Within the historic core of buildings real change can be seen as the roofs have been removed and timber repairs undertaken. Elsewhere, the newly rebuilt Stove House 5 has shot up and is beginning to look like a building once more.

Rebuilding the flues in Pan House 3

The stove of Pan House 3 has slowly been repaired where it had begun to collapse on all sides.

The original flues that ran under the pan into the stove house (See Building a Pan House and building a Stove House http://thelionsaltworks.blogspot.co.uk/2013/05/how-tobuild-open-pan-salt-works.html) had collapsed. These were rebuilt entirely. 

The remainder of Pan House 3 wall that had been dismantled was rebuilt and steel lintels put above the existing doorways.

Removing the roofs and repairing the trusses

The roof of Pan House 3 and 4 have been removed. This involved carefully taking off the sheets. 

This has allowed the timber repairs of the roofs to progress. Many of the roof trusses have had to be patched repaired and whole elements replaced where they have rotted away.

New steelwork has been added to strengthen and support the original trusses.

Clearing Stove House 2

The ground floor of Stove House 2, was entirely redesigned in the late-1960s. This involved the insertion of an automated salt scraping and drying mechanism. Although not unique, (systems like this were built in Winsford), it was highly unusual as salt had begun to be made by the Vacuum Salt Process (still used today at British Salt, Middlewich).

The mechanism involved an automatic salt-scraper across the pan and a series of conveyor belts around the ground floor, which carried the salt into the warehouse. 

The salt passed slowly along the conveyor belts and was dried by hot air recycled from the stove in Pan House 2.

The whole of this area was covered in debris that had to be cleared prior to building work in Stove House 2.

Building Stove House 5

Stove House 5 was dismantled in 2009, in order that it could be entirely rebuilt as the new visitor and conference centre. This adopted the original location and plan but had a new concrete base (see March Update http://thelionsaltworks.blogspot.co.uk/2013/05/march-2013-foundations-and-wall-repairs.html).

The framework for the new structure was largely new but reuses the previous brickwork and wood frame and panelling throughout. The framework was built of steel off-site and brought to site like a giant ‘Meccano’ set. It was then constructed using cranes and cherry-pickers by a small crew of steelworkers in just one week.

Concrete was poured to create the first floor of the building.

Between the steel frames, breeze-block work has been built and this has been clad in brickwork, using the original bricks removed from Stove House 5 in 2009.

The original wooden frames of the roof have been stored in a large temporary building since 2009. they have been laid-out to be rebuilt in the new building.

How to...Transport Salt

The transport to the site went through change over time that correlated with the wider change in transport.

Canal and River

Much of the 19^th-century open-pan salt works in Northwich developed along the line of the Trent and Mersey Canal. Initially the Alliance Works and the early Lion Salt Works relied on the canal network to transport salt along the canal to the Anderton Boat Lift and down the River Weaver. Photographs show salt being loaded onto canal barges outside the Lion Salt Works in the late-19^th century.

The works had its own fleet of narrowboats which shuttled back and forth along the Trent and Mersey Canal between the works and the Anderton Boat Lift carrying 30 ton consignments of salt to the waiting Weaver Flats and barges. Their names were Duke, Earl, Ernest, Tempest and Typhoon.

From here it was relayed to larger barges that ran along the River Weaver. Buried remains of salt chutes form part of the Scheduled Monument of the Anderton Boat Lift (SM no. 1021152). These would be used to transport salt directly into the waiting barges below. The Thompson’s also owned a fleet of Mersey Salt Barges including the Herald of Peace and Weaver Belle.

The 19^th century maps suggest that coal was delivered to the open pans of the Alliance Works from a private basin. Likewise coal was delivered directly into the earliest Lion Salt Works from the canal. Coal could be directly delivered from the canal to Pan House 1. In addition a tunnel ran from the canal into the centre of the works. The tunnel allowed coal to be delivered to the series of four fishery pans.

Rail - Salt Trains/ Carriages

The works also relied on the rail network in parallel with the canal. Salt was transported from the Alliance Works to the main rail network via a series of tramways. These tramways ran to the Marston Hall Mine (north-west of the LSW), The Adelaide (Open-Pan) Works (north of the Trent and Mersey Canal) and The Alliance Works which developed a series of sidings that ran into the centre of the works. From here the tramway snaked around and joined sidings in Northwich on the main Chester – Manchester line (name railway).

After the Alliance Works closed in c. 1900, new sidings were put in place that served the Lion Salt Works. They ran around the southern boundary of the site and finished in front of Pan House 3 and 4. The sidings were not designed for trains to use but were instead designed for salt wagons that were brought up to the works by a series of winches from the mineral railway that served the Marston Mine. The wagons used to wait in a sidings at the bottom end of Cross Street (the house today is called The Sidings).

A single windlass is still visible in the Pump House. This was powered by the steam engine in the pump house and drew the wagons up the gradual incline from the end of Cross Street. A series of pulleys and couplings are likely to have allowed the carriages to negotiate the twisting route of the siding.

The Wagons

Two types of wagons operated at the works.

• Open roofed coal wagons. See picture. These brought coal directly to the barricades of the pan houses where it was unloaded ready for use in the stoves.
• Covered salt wagons. The salt wagons were covered in order to protect the salt from rain. The pitched-roofed variety dates to the 1900s. Later salt wagons after the 1940s had roofs that were barrelled.

The salt wagon now located at the site is not original to the works but was brought to the site by the Lion Salt Works Trust in the 1990s.

The van was probably built in Wakefield in c. 1900 by Charles Roberts and Co. The remains of painted lettering on the side of the van show that it was originally part of a fleet owned by Chance and Hunt Ltd of Oldbury, Wednesbury and Stafford. The company was absorbed by Brunner Mond and Co Ltd in 1917 before being taken over by ICI Ltd in 1927. The remains of ICI lettering are still visible overwriting the original lettering. Previous surveys (1991) have noted that it is possible to see the words [repairs advise] and [Winsford].

At the end of its working life it remained at ICI sidings in Northwich until 1977. It then passed into the hands of the Conway and Llanrwst Railway Society, North Wales. In 1987 members of the Foxfield Light Railway helped transfer the van from Dyserth Quarry to Blaenau-Ffestiniog, where it formed part of a private collection belonging to Mr R Morris. The wagon was brought to the Lion Salt Works in September 1991 and has remained on the private railway sidings since.

Road – The Loading Bay

During the final years salt was taken directly from the works to the docks at Liverpool using road transport. Vans would back up to loading bay beside Stove House 4. Salt would be packed directly from Stove House 4, the Packing Area and Stove House 2 into the vans. This was how the Lagos Salt was exported.

How to...Process and Package Salt

After the salt blocks had reached the warehouse it was processed and packaged in a number of ways. Some of the processes were manual whilst others used a variety of 'Heath Robinson' machines to process the salt.

The Crushing Machine

The crushing machine was originally located in the warehouse of Stove House 2 at the north of the site. It was powered by a steam engine that sat on a brick base outside the stove house. The steam engine in turn was powered by steam from the boiler in the Engine House/ Brine Tank. It probably dates to around c. 1900 when Stove House 2 was built.

The crushing machine was moved to Stove House 4 when it was rebuilt in 1956. Henry Thompson the final owner and manager of the works recalled in 2009 how he dismantled and rebuilt the crushing machine in its new location.

Power

When it was rebuilt it was powered by an electric motor sat on a stand east of the crushing machine. This powered a series of two belts and wheels.  A large flywheel mounted on the northern side allowed the motion of the belts to be continued. All the mechanisms within the work were powered from this individual mechanism.

Cogs

A series of cogs powered the internal mechanism. These were a 30 cog, 28 cog, 74 cog gears on the northern side (see north elevation) and two series of 28 cog gears on the southern side (see south elevation).  This powered the internal crushing mechanism.

Bucket Lift

A belt ran to an upper wheel on the southern side that powered the chain lift that raised the salt buckets on the western side. These brought blocks of salt from the flue level of the stove house and deposited them automatically in the central crushing mechanism.

The Crushing Mechanism

The upper part had two large toothed/ hooked barrels that turned towards each other crushing the blocks of salt. The lower mechanism had paddles that separated the crushed salt into four individual chute. The salt ran down the chutes and was bagged at the bottom.

Why was the salt crushed?

Two sorts of salt were produced in the work. Fine and Coarse Salt (see salt science). It was the blocks of fine salt that were placed in the buckets and crushed. 

Some salt was sold as blocks whilst others were crushed. This was part of the marketing of the salt. Some salt was sold in small blocks like loaves of bread and were not crushed. This type of block salt was common throughout the 19^th and early 20^th century. It continued to be popular in the later 20^th century in the Cheshire region where housewives continued to prefer the block salt. These blocks were cut up by a series of saw blades (see the cutting machines below).

The blocks allowed salt to be preserved for longer in damp households. Salt hardens when it is in damp air and granular salt will usually harden into a block. If the salt was bought in block form a small amount could be removed and used as and when needed. This was usually crushed using a rolling pin.

The blocks would also be crushed to provide ready-made granular salt. The salt produced in blocks from the fine pans would be suitable for the table and would often be sold in sacks ready for repacking as table salt.

The salt that was sold to Africa known as Lagos Salt was crushed prior to sale. It was not the block salt produced in the fine pans but was salt from the warehouses that were crushed from its hardened state prior to sale.

The Cutting Machines – The Packing Area

The cutting machines used large circular saws to cut the block salt into smaller blocks that were sold in packets (like loafs of bread). This was the traditional way salt was sold since the 19^th century. It was then crushed in the house using a rolling pin or mortar and pestle. This practice survived into the 20^th century in Cheshire into the 1970s when local housewives preferred to buy their salt in blocks.

 A further modern crushing machine was located in the Packing Area. This was powered by two electric motors with opposing ridged barrels. The salt fell onto a small conveyor belt and passed through the wall to Stove House 4 where it was sorted through the hopper in Crushing Machine 2.

Stove House 5 Excavations

History of Stove House 5

Stove House 5 was built in 1965 by Henry Thompson. It was the last of the five Stove Houses to be constructed on site. The associated Pan House 5 lay to the east. The pan and stove house began to decay badly and the pan house entirely collapse in the 1990s. The stove house survived but a huge gap had opened in the south-east corner and the whole complex was dismantled in 2009.

The Restoration

As part of the restoration the stove house is being rebuilt and will form the museum entrance and shop on the ground floor with conference facilities on the first floor. The rebuilding of Stove House 5 involves the excavation of the entire footprint and the pouring of a concrete raft to take the weight of the new building.

Archaeological Excavations

Scheduled Monument consent requires an archaeological excavation to be conducted before the construction of the concrete slab.

Archaeological Excavations have been undertaken in January and February 2013 by Oxford Archaeology North. This involved the machine excavation of an area 20m by 20m in size. The remains of brick buildings were then cleaned by hand and then surveyed, drawn, photographed and recorded.

The Alliance Works

The Thompson family originally had an earlier works located east of the current buildings. This was known as the Alliance Works and existed from 1856 until 1889 when it was sold to the Salt Union. http://thelionsaltworks.blogspot.co.uk/2012/11/the-lion-salt-works-history-of-site.html Records of the earlier salt works are limited, but excavation undertaken in 1994 identified these buildings for the first time. Earlier excavations in 2011 by Oxford Archaeology North identified the remains of flues from a Stove House. http://thelionsaltworks.blogspot.co.uk/2013/05/how-tobuild-stove-house.html

The current excavations have revealed the remains of the boundary wall between the earlier Alliance Works and the later Lion Salt Works. Along this boundary was a small cottage. The cottage may have been where the Thompson’s lived and managed the earlier works. It also appears to have acted as a pan smithy for repairing the pans of the Alliance Works. A large hearth was located within the remains of the buildings. 

In addition a large machine pit suggests there was a steam engine north of the building. A series of cobbles formed a yard to the west of the cottage.

The Fishery Pans

Documentary Research has revealed that a series of four ‘fishery pans’ existed on the site in the early 20^th century that were replaced by Stove House 4 in the 1950s. Fishery pans – so called because they provided coarse salt for preservation in the fishery industry [ADD LINK TO MAKING SALT] – were much simpler and consisted of a single open pan over a stove. Four existed on site.

Excavation revealed the foundations of one of these fishery pans. No flues were revealed but the remains of brick piers along the edge of the stove and the base of a further large chimney was excavated at the north of the stove.

Stove House 5

Overlying the remains of the fishery pan was the brick walls of Stove House 5. 

March 2013 - Foundations and Wall Repairs

Repairing the pan bases

The metal pans in which the brine was boiled [How to make salt insert link] rested on large brick bases called stoves. This was where the fire was lit. Unfortunately the weight of the pans caused the walls of the stoves to fall outward. Brick piers have been built along the sides of the pans by the Thompson Family but these have not prevented the walls collapsing outwards.

In order to repair the stoves it has been decided to sandwich them in concrete. Slabs of concrete are built either side and then they are held together by metal rods called cintec anchors.

The cintec anchors

The cintec anchors have been carefully drilled through the stove in several places. 

These are encased in a fabric and plastic sock and then encased in concrete themselves. Two slabs are put on either side of the stove walls connected to the rods by metal plates. These are tightened and this holds the walls of the structure together.

Excavating the footings for the stove house steel work

The stove houses have two levels: the drying level and the warehouse level [How to Build a Stove House insert link]. The warehouse floor is held up by rails supported by metal columns. Unfortunately the metal columns have corroded badly and cannot now support the floor above safely. Instead a whole new steel superstructure will be built to compliment the earlier rails. One of the jobs has been to build a new series of concrete strip foundations on which the whole structure will rest. This involved excavating narrow strip footings between the flues of the drying level.

Rebuilding the northern wall of Stove House 3

In 2002 the wall between Stove House 3 and Stove House 1 entirely collapsed. It had been weakened by parts of the structure being removed to make the warehouses one large space. Rain and water got into the structure through the leaky roof and it subsequently collapsed.

In order to support Stove House 3 at its northern end an entirely new wall had to be built. This reused the footprint of the original wall, which itself was part of a much earlier wall associated with the Red Lion Hotel http://thelionsaltworks.blogspot.co.uk/2012/11/the-lion-salt-works-history-of-site.html.

Building Stove House 5 – The Concrete Base

After the completion of the excavation the work began on the construction of Stove House 5. Stove House 5 was dismantled in 2009 as it was in very poor condition. It was to be rebuilt using original materials combined with a new steel superstructure and would act as the visitors centre and conference facilities for the new museum. 

The first job was to build a large concrete raft designed to take the weight of the new building. The old building had been built on very shallow foundations and this was part of the reason why it had collapsed.

 

How To…Build an Open Pan Salt Works

What makes up the buildings of an open pan salt works?

What does each building do?

In this part I will try to explain how an open pan salt works … well works!

This page is being constructed in parallel with the site restoration so if you can’t find a link it probably has not been written yet. Hold tight it will be on its way.

Brine Extraction

In order to make salt you need the raw product and this was extracted from the ground by a brine shaft or bore hole. The salt would be raised from the ground by means of a pump. But often the pressure of the underground stream would be strong enough to lift the brine from the ground alone.

On the site at the Lion Salt Works we have a number of buildings associated with Brine Extraction.

• ·        Originally there was a brine shaft with a headstock.
• ·        This was replaced by a nodding donkey and pump.
• ·        The brine passed around the site in pipes.
• ·        Finally the brine is stored in the brine tank.

How to extract brine from the ground? [http://thelionsaltworks.blogspot.co.uk/2013/05/how-toextract-brine-from-ground.html]

Salt-making: The Pan House

The Pan House was where the salt was made. This involved heating the brine in the large metal pan.

How to make salt by the open pan method? [insert link]

It consisted of a brick stove where fires were lit, the pan and the wooden structure around.

How to build a Pan House? [http://thelionsaltworks.blogspot.co.uk/2013/05/how-tobuild-pan-house.html]

The Lion Salt Works had five pan houses in the 1980s (numbered 1-5).

• ·        Pan House 1 was demolished in the 1980s before the works closed in 1986 and is now a garden.
• ·        Pan House 2 has largely fallen down but the pan and stove survive.
• ·        Pan House 3 and 4 survive intact and are due to be restored.
• ·        Pan House 5 was dismantled as part of the 2009 enabling works.

Salt-making: The Stove House

From the pan house the salt passed to the Stove House for drying. This was a large brick building that used the heat from the stove in the pan house to dry the salt in blocks. The upper part was a warehouse for storage and processing.

The Lion Salt Works had a stove connected to all the pan houses that survived into the 1980s (again numbered 1-5). Four of these survive whilst the fifth will be rebuilt.

• Stove House 1 (AKA The Link Block) – this originally connected to Pan House 1 and was one of the first built on site in the 1890s. It has almost entirely collapsed.
• Stove House 2 survives on site next to the canal. It again dates to the 1890s. It has a timber first floor unlike all the other stove houses.
• Stove House 3 runs next to Ollershaw Lane and dates to 1900. It is made of brick with distinctive rail tracks used to support the warehouse floor.
• Stove House 4 was built in 1956 to replace a series of four common pans [see link].
• Stove House 5 was built in 1965. It has been dismantled but will be rebuilt as a purpose built area of the new museum.

How to build a Stove House? [http://thelionsaltworks.blogspot.co.uk/2013/05/how-tobuild-stove-house.html]

Salt-making: The Warehouses and the Salt Store

The warehouses were purpose built into the stove houses. These were used to process and pack the salt.

The lower grade common salt was stored in a large store house. The only surviving salt store on the site is the Coronation Salt Store located on the western side of Ollershaw Lane.

How to process and package salt? [http://thelionsaltworks.blogspot.co.uk/2013/05/how-toprocess-and-package-salt.html]

Transport to and from the salt works

The transport of raw material to and from the Lion Salt Works was very important. The most important raw material needed apart from brine was fuel for the stoves. This was originally coal but was changed to oil in the 1970s.

The transport that brought the coal to the works also took the salt away. The change in transport use can be seen throughout the works.

• ·        The canal side
• ·        The rail lines
• ·        The loading bay

How to transport salt? [http://thelionsaltworks.blogspot.co.uk/2013/05/how-totransport-salt.html]