HISTORY

The Etruria Industrial Museum Site 
The Etruria Industrial Museum is the home of Jesse Shirley’s Bone and Flint Mill (Etruscan Mills) which was an important supplier to the pottery and agricultural industries from the early 1800s to 2011. It is located at the junction of the Trent and Mersey and Caldon Canals which since their opening in the 1770s has provided an ideal location for various industries due to its excellent transport link. Etruria Wharf, located on the site of the present car park, was very important in the conveyance of goods to and from the various factories in Etruria, Shelton and Hanley. A horse drawn wagon tramway ran across what is now Etruria Vale Road, between the houses on the opposite side of the road and up the hill to Hanley.  A statue of James Brindley (1716 – 1772) the most famous canal engineer of the era is located opposite to the visitors centre.

As well as Jesse Shirley’s Mill there is a working forge, canal warehouse and check office, the summit lock of the Trent and Mersey canal, the only staircase lock in Staffordshire and the site of the first public hospital in what was to become Stoke-on-Trent built in 1803 and called the Dispensary and House of Recovery. The site was later occupied by an early gas works.

From the late eighteenth century the area was occupied by Ball’s dye works. In 1820 Bourne and Hudson began boiling and calcining bones on the site which provided size sold as glue and calcined bone which was transported for grinding to Bell’s Mill, rented premises in nearby Cobridge Road. In 1842 John Bourne bought the mill and on his death in 1852 his step sons, Jesse and Joseph Shirley inherited. It was Jesse that built the new mill in 1856 which can be seen operating today.

Jesse Shirley’s Bone and Flint Mill

 During the first part of the 18th century the beneficial use of ground flint and bone was discovered. Flint (i.e. silica, up to 50% of the total) can be added to clay to produce earthenware products, it gives the ware strength, whiteness and prevents shrinkage during firing to make a hard cream product. The problem with grinding flint using the technology of the day was that it produced clouds of dust; the workers quickly died of “Potters Rot” (silicosis of the lungs) and would not undertake the work. Consequently, the wet pan grinding method was developed to reduce harmful dust; this is illustrated at Jesse Shirley’s Bone and Flint Mill.

Cattle bones were found to be the most suitable for adding to clay (again up to 50% of the total) to produce bone china. It is the bone which gives the ware its characteristic translucent quality, it is whiter than other ware and its high strength allows it to be finer.
About 1747 it was discovered that Cornish stone (a partly weathered granite) mixed with china clay would form a porcelain body. Small quantities of Cornish stone were also processed on site.
The two processes for bone and flint were similar and the ground products revolutionised the ceramics industry; existing water powered corn mills were converted and new water mills were built. Wind could not supply the continuous high power required, but steam power was an obvious application as steam engines became more powerful and reliable. Thus building of the steam powered Jesse Shirley’s Mill was commenced in 1856 at the Junction of the Trent and Mersey Canal and the Caldon Canal as canals offered cheap transport of these heavy raw materials.

Jesse Shirley was born in 1819. In 1834 he was employed by his step-father John Bourne at his firm of Bourne and Hudson Bone Works, originally as a writing clerk. When John Bourne died in 1852 he left the business to brothers Joseph and Jesse Shirley. It was the latter who had the present Mill built in 1856/1857. The road access to the site was poor but the location was chosen because of the proximity to the canals and the availability of a wharf so providing easy access to many local potteries and to all parts of the country.

Bone, usually from cattle would originally have been sourced locally but as demand increased it was sourced from various parts of the country and latterly from overseas. Flint was from the south and east coasts of England and near continent.

Calcining Kiln

The kiln was used to calcine (roast) flints and bone to approximately 1000 degrees centigrade to change their nature and make them suitable for grinding to a fine powder.

Flints are an unlikely raw material for pottery as they are hard and black in their natural state. If they are calcined above 1000 degrees centigrade crystalline water is driven off to leave a softer, lighter and whiter product.

The calcining kiln consists of two chambers with a hovel built above them to create a draught to aid combustion. Filling the kiln was a very skilled job requiring layering of fuel and either bone or flint. Flints would be built up in layers with slack (small pieces) coal using approximately 1 hundredweight (51Kg) of coal per 1 ton (1.02 tonnes) of flint. It would be allowed to combust for 8 to 16 hours (depending on the fuel and climatic conditions) and then left to cool before being withdrawn through draw holes at the bottom.  Production of ground flint ceased at the Mill in the 1930s

Bone was treated in a similar way after first being boiled to remove tissue, this would produce glue, a saleable by-product.  Wood was used as the fuel as bone is more combustible and is prone to contamination from iron pyrites in coal.  Calcined bone is softer and whiter than in its natural state.

Crusher Room

This is now entered down steps, but originally the floor was level with the canal wharf outside. Mining subsidence has lowered the whole area by about 6 feet (2 metres) and the canal wharf has had to be raised to maintain the canal level – see the blocked up lower part of the windows in the Gear Room. Here are the two draw holes for the kiln.

The crusher was installed in the 1930s after the calcining kiln seen today was decommissioned. It is of the oscillating jaw type, belt driven by a small horizontal steam engine of unknown manufacture and date and was used to crush oversize flints and Cornish stone.

Gear Room

Power is transmitted via the flywheel axle of the engine through a ratchet which enables the engine to be barred backwards by hand if it has stopped on a dead centre without moving any of the machinery backwards. Rim gears transmit the power to long line shafts which run the length of the room, one shaft is currently driven. Along each line shaft are five bevel gears which drive vertical shafts taking the power to the pan room above.

To separate coagulated particles in the ground mix it was run off from the pans in the upper room through wooden launders to one of three wash tubs where rotating paddles stir the mix and ‘blunge’ it through the vertical bars of the paddles.

The mix was then run into one of two rectangular settling arks. Much larger arks holding 25 tons (25.4 tonnes) of liquid were beyond the gear room wall and have been lost during development of the site. As the solid particles settled wooden bungs in a vertical plank were knocked out to run off the clear water. This left a thickened slop which could be put into barrels and sold or pumped to drying beds (which have been lost) where water was evaporated off and the solid product sold as blocks. Above the arks is a rare ‘Pulsometer’ steam pump. It has two chambers, steam pressure empties one side whilst the vacuum from condensed steam draws fresh liquid into the other side. A steel ball then rocks over a knife edge to allow the process to be repeated on the other side.

Pan Room

Material to be ground was hoisted through a hatchway in the floor from the Gear Room below. The slack chain hoist was driven from the extended vertical shaft of the small end pan. The material was tipped into one of ten pans and water was added. The pan floor is composed of chert blocks with the gaps filled with pitcher’ (broken biscuit ware). Power from the floor below rotates sweep arms which push large chert blocks or ‘runners’ around the pan. The material is pushed and tumbled around the pan and is ground in the process.

The larger diameter pans contain runners of up to 1 ton (1.02 tonnes) in weight and a hand crane at one end of the room was used to lift these into the pans. After about 8 hours for flint, less for bone, the material was ground and could be run out of the pan to the floor below for further processing.

Boiler Room

Steam is generated in a ‘Cornish’ boiler built at the nearby Cliffe Vale Boiler Works in 1903. It is hand fired with coal and contains about 2,500 gallons (11,000 litres) of water,  indicated in two water gauge frames with the steam pressure by a Bourdon gauge. The dead weight safety valve releases pressure at 60 pounds per square inch (4.2 kg force per sq. cm), although the boiler is operated at less than half that pressure. It is important to maintain the water level in the boiler and new water from a large iron tank in the roof was originally pumped in, against boiler pressure, by two Weir steam pumps. Examples can be seen against the side wall. Today electric pumps are used.

Steam is taken off from the top of the boiler through a large diameter pipe and taken to the engine room next door

Boiler Room

Steam is generated in a ‘Cornish’ boiler built at the nearby Cliffe Vale Boiler Works in 1903. It is hand fired with coal and contains about 2,500 gallons (11,000 litres) of water,  indicated in two water gauge frames with the steam pressure by a Bourdon gauge.

The dead weight safety valve releases pressure at 60 pounds per square inch (4.2 kg force per sq. cm), although the boiler is operated at less than half that pressure. It is important to maintain the water level in the boiler and new water from a large iron tank in the roof was originally pumped in, against boiler pressure, by two Weir steam pumps. Examples can be seen against the side wall. Today electric pumps are used.

Steam is taken off from the top of the boiler through a large diameter pipe and taken to the engine room next door

 

Engine Room

“Princess” is a double acting condensing rotative beam engine to the design of James Watt. She was purchased second hand and installed when the mill was built in 1856/7. Her previous history is unknown but she is thought to have been built by Bateman and Sherratt of Salford, Manchester in the 1820s who were rivals and competitors of Boulton and Watt.

Steam enters the single large vertical cylinder through a main steam valve and is directed to one end of the cylinder via valves which are operated by a rocking shaft beneath the floor which is, in turn, operated by an eccentric from the flywheel axle. Exhaust steam is converted to water in a condenser (cooled by water from the canal) located beneath the floor. This creates a vacuum in the condenser which is opened to the other side of the cylinder thus the pressure difference between steam pressure on one side and vacuum on the other moves a piston within the cylinder. The valves change over and the process is repeated on the other sides of the piston. The two gauges on the wall show the strength of the vacuum and steam pressure.

For the engine to be double acting (pull and push) the beam must have a solid connection to the rod which emerges from the cylinder head through a ‘metallic’ gland packing. The piston rod must travel in a vertical straight line but the end of the overhead beam which transmits the power transcribes an arc as it rocks. This would try to pull the rod backwards and forwards which it cannot be allowed to do. James Watt overcame this problem with his great invention – parallel motion; a trapezoidal connection. At the other end of the beam is the sweep rod which connects via a crank to the axle which carries a flywheel of 20 feet (6.1 metres) in diameter and 10 tons (10.16 tonnes) in weight. The flywheel’s momentum carries the engine over top dead centre and bottom dead centre when the piston is at the end of its stroke and is not providing any power. The axle extends through the wall into the gear room.

Restoration

In June 1978 Jim Kelly, then the Keeper of Social History at Stoke-on-Trent Museum, called for volunteers to restore the Mill and machinery.

It had been in continuous use from 1857 until work stopped when modern machinery on site had been commissioned to replace it in 1972. During that time it had seen little alteration, it had become neglected during its latter days, but was essentially as it had been built well over a century before. The first working party took place on 22nd October 1978 and voluntary work has continued to the present day, some of the original volunteers are still on the team over 34 years later.

The site’s historical significance was recognised in 1975 with it being designated a Scheduled Ancient Monument with the buildings being grade 2* listed. The site was officially opened to the public by Fred Dibnah on 6th April, 1991. It continues to be maintained and operated by volunteers.

Canals

It is by no coincidence that Jesse Shirley built his Bone and Flint Mill in Etruria on the junction of the Canals. The waterway links would provide a clean, safe and cost effective means to transport materials to his customers who were bone china manufacturers and included many household names such as Wedgwood, Aynsely and Doulton.

Trent and Mersey Canal

In 1761, Josiah Wedgwood showed an interest in the construction of a canal through Stoke on Trent for the fast and safe transport of his pottery. Wedgwood’s plan was not to connect the two rivers by canal, but to connect the potteries to the River Mersey, and thereafter the port at Ellesmere.

In 1771, Wedgwood built the factory village of Etruria on the outskirts of Stoke on Trent, close to the Caldon canal. The plan of a canal connection from the Mersey to the Trent was authorised by an Act of Parliament in 1776 and the first sod was cut by Josiah Wedgwood in at Middleport. The engineer James Brindley completed the canal in 1777, including more than 70 locks and five tunnels.

Up until 1777, pots had to be carried on the short journey from Etruria, over the top of Kidsgrove Hill, and to the other side, where the canal had been constructed to Ellesmere Port. The only obstacle that still had to be tackled by the canal company was the hill at Kidsgrove through which the Harecastle Tunnel was being dug.

The Trent and Mersey canal was built to link the River Trent at Derwent Mouth in Derbyshire to the River Mersey.

The Harecastle Tunnel was actually two tunnels. The first built by James Brindley measured 2,880 yards (2,633 m) long. Barges were ‘legged’ through by men lying on their backs and pushing against the roof with their feet. This was a physically demanding process and created major delays. The civil engineer Thomas Telford was commissioned to build a second, and wider, parallel tunnel with a towpath. This 2,926 yard (2,676 m) long tunnel was opened in 1827.

In the 1900s, the Brindley tunnel was closed due to severe subsidence, but the Telford Tunnel – although also prone to the same problems – remains in use, and is the fourth-longest navigable canal tunnel in the UK.

Caldon Canal

The Caldon Canal commences at Etruria, immediately adjacent to the top lock of the Stoke flight on the Trent and Mersey canal. A statue of James Brindley, the engineer for the Trent and Mersey main line, stands near the junction.

Following the course of the River Trent, the waterway climbs to a summit level at Stockton Brook, which carries it over the watershed between the Trent and Churnet Valleys. Thereafter the canal descends through locks at Hazelhurst and then Cheddleton, into an initially broad flood plain.

The first plans by Trent and Mersey Canal Company to construct a canal from the summit level to Leek were considered in January 1773. This would have been a tub-boat canal, as the boats were designed to carry just 5 tons, and rather than using locks, inclined planes were to be used at points where the level of the canal needed to change.

Two more plans were considered, and the third included extra reservoirs which would supply the summit level of the existing main line. Having secured contracts with several owners of limestone quarries in the Caldon Low area, the company sought an Act of Parliament to authorise construction of the new works, which it obtained in May 1776.

Canal Warehouse, Check Office and Gauging Dock

The warehouse was used in the 1800s by the Canal Company and later by British Waterways (now the Canal and River Trust) to store goods and equipment. Attached is a gauging dock where boats had their cargoes ‘gauged’ and check office where they paid the toll charge.  

Summit Lock of Trent and Mersey

This lock is the highest on the Trent and Mersey it is downhill all the way from here. The Caldon canal is a feeder canal conveying water from Rudyard Lake ,near to Leek in the Staffordshire Moorlands to replenish the water lost in both directions.

Staircase Lock on the Caldon

Officially known as the Bedford Street Double lock, this is the last existing staircase lock in North Staffordshire.

 The Forge

The original forge stood on the site for over 150 years before being re-built in 1969. Many of the original bricks were reused but turned round so that the original interior paint can be seen on the outside. Originally there were stables attached. It was used commercially until the 1960s when it became derelict. Today it is used by an artistic blacksmith who gives demonstrations during special events including steaming weekends.

Dispensary and House of Recovery

The first public hospital in North Staffordshire

The 18th century saw the region which was to become Stoke-on-Trent change from a small rural community to an industrial conurbation. With increased population density and industrialisation the health of the inhabitants was poor. The sick were treated at home using ‘old wives’ remedies, self help books, advice and prescribing of drugs by the local Apothecary or the intervention of a Surgeon – if one could be afforded. Industrial diseases such as ‘potters rot’ caused by inhaling silica dust mainly from the grinding of flints and the use of flint dust during the firing process and lead poisoning were common. Medical science was developing and it was apparent that improvements had to be made in health care, especially for the poor.

Voluntary Hospitals began in London; the first ‘The Westminster’ opening in 1719. They were characterised by their independent status and reliance on philanthropy and other private sources of funding. Administration was by committees of lay governors serving in a volunteer capacity and they were staffed largely by physicians and surgeons working in honorary and unpaid posts who dispensed free medical attention and drugs to the poor as out patients. The movement spread across the country and in July 1802 a meeting was held at the Swan Inn, Hanley to consider “establishing a Medical Dispensary, and a Ward for the reception of Fever Patients.”

In the field near to the lock is the site of the first public hospital in North Staffordshire opened in 1804. The inspiration to found a hospital came from local employers including Josiah Wedgwood II. The Dispensary is where patients came for diagnosis, treatment and inoculation against smallpox which had been recently been introduced following the pioneering work of Dr Edward Jenner. Medical science and the processes of life had been greatly advanced by the work, especially on gases, by such notables as Erasmus Darwin, Joseph Priestly, Humphrey Davy and Antoine Lavoisier all known personally to the Wedgwood family. The latter had given generous donations to Dr Beddoe’s Pneumatic Institution in Bristol which had treated Tom Wedgwood and the son and daughter of James Watt and where Humphrey Davy worked. Josiah II offered to rent (purchased in 1812) a plot of land between the Trent and Mersey, and Caldon canals to the committee.

The Staffordshire Advertiser, an influential local newspaper took up the cause and around £800 was raised, a small amount compared with the £27,000 raised by Derby for their hospital but sufficient to commission Mr Bellhouse of Manchester to draw up the plans for a building comprising two parallel wings and to commence constructed by Mr Coxon of Hanley. Additional funds were raised, including a legacy of £800 and Josiah Wedgewood II became treasurer with the accounts being handled at his manufactory pro bono. The Dispensary opened in April 1804 and the eleven bed House of Recovery, a euphemism for a fever ward, shortly after. Later it was decided to admit general and accident patients so providing an infirmary. Additional building work was undertaken.

The paid employees consisted of an apothecary, who was in effect the general practitioner attending patients, dispenser of medicines and secretary to the trustees, a matron, and a small number of nurses and support staff. The work consisted of dealing with general illness, diseases caused by lead and dust and accident cases related to the pottery, mining and iron industries. Good work on the prevention of illness progressed with a program of vaccination against smallpox (developed by Edward Jenner in 1796-8) and encouragement to factory and mine owners to improve safety.

The institution continued to operate until 1819 when it had been realised that larger buildings were required and the site was not suitable for expansion. A new infirmary was erected in Etruria close to the Newcastle to Leek road with much better access. The new institution operated until 1869 when it was moved to the healthy and quiet suburb of Hartshill. It became the North Staffordshire Royal Infirmary and with the City General Hospital is now the University Hospital of North Staffordshire.

During 2013 Volunteers of the Museum lead by Sheffield University archaeology student Hannah Holbrook and kindly supported by the University, will carry out a geophysical survey of the site in the hope of finding the foundations and establishing its exact location and ground plan.