Pool - Middleton Hall Tamworth

The Waters of Middleton Hall
Figure 1. The Pool from the south east
Introduction
Middleton Pool was formed by damming the Langley Brook.
This is one of the most significant tributaries of the River Tame and
one of the least-affected by pollution. Such pollution as there is now
in the waters of the brook is the result of the upstream use of
fertilisers by farmers. The brook, which rises close to Langley Hall
in the Falcon Lodge housing estate on the edge of Sutton Coldfield is
joined by Colletts Brook, which rises close to Bassetts Pole before
passing below Middleton Village and entering the Middleton Hall
Estate. Together the two brooks drain about 15 square kilometres so
that about nine million tonnes of water pass through the pool in a
typical year. This makes the Langley Brook one of the most
significant sources of water power in the vicinity of Birmingham. As
shown in Figure 2, the fall from the sources to the pool is about 50
metres, the pool being about 70 metres above the sea level.
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Figure 2. The Langley and Colletts Brooks catchment area.
The pool did not occur naturally. It was man made as a
means of storing the water to power machinery, as will be described
later. Before this there would have been a stew pond – a small fish
farm – because the brook runs through a former deer park, where it
was usual to have a source of fish to complement the meat that was
taken from the Chase.
In the following, what we know about the pool will be
recounted. It will show how Middleton Hall played a part in the
growth of Birmingham, how electric power came to this remote
location and describe the consequences of violent storms. It will also
describe the ravages caused by gravel extraction.
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The Earliest Records
These come from the Domesday book of 1086, where it is
recorded that Hugh de Grantsmesnil had a mill at Middleton. This
would have been on the Langley Brook, but where is not recorded.
Two mills were recorded in 1291. One was presumably at Fisher's
Mill, the other somewhere higher up the stream. The first series
Ordnance Survey map of 1872, for which the data is from between
1814 and 1817, shows Fisher's Mill (Figure 3).
Figure 3 1872 OS Map showing the waters around Middleton.
In Figure 3 the Langley Brook and Middleton Pool are shown
in blue, the Fazeley Canal in green and the River Tame in light blue.
The map shows no other mill nor was another recorded after 12911.
The moat around the house was fed by the small local stream
below the pool when it was first created. This was probably at the
time of the building of the first manor house in the late thirteenth
century. It passed just in front of where the Jettied Building stands,
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down the west side of the West Lawn and close to the South and East
Wings. The moat walls are still in evidence from the north west
corner and round the west, south and east sides of the house. The
moat was originally across the front of the house, as evidenced by the
findings of a dig2 that revealed the footings for a bridge and showed
that the moat had filled up with waste material, including meat bones
and bottles.
It is probable that the stew pond was enlarged in the sixteenth
century when the first Francis Willoughby was responsible for the
making of iron in the park.
Birmingham: Middleton's Part in its Rise
John Leland3, the first man to record his travels around
England, reported that there were many blacksmiths working in
Birmingham in 1538. Leland reported that they got their coal and
iron out of Staffordshire. Before the sixteenth century Birmingham
was scarcely populated. It was the displacement of peasants from
their land following the Act of Enclosure in 1515 that began its rise.
Prominent among those displaced were the blacksmiths, who were
not needed by landowners raising sheep and it was they who found
ways to survive in the Midlands, despite the dearth of water power
and the fact that nothing much would grow.
Initially the
blacksmiths would have obtained their iron from smithies where
small quantities of iron were produced using the bloomery hearth
process (see the appendix). These were scattered around, mainly, as
Leland observes, in Staffordshire, most of them around and north of
Walsall.
The Birmingham blacksmiths' businesses soon grew to
exceed the ability of the smithies to meet the demand, the few
smithies being able to each produce only about a ton of bar iron
every eight days.
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The far more productive blast furnace process was already in
use in Kent, Sussex and the Forest of Dean, but there were no roads
and transport was impractical.
The first blast furnaces in the Midlands were established by
Lord Paget who had three ironworks in Cannock Chase in 15534.
There is an immediate link to the Willoughby family of Middleton
Hall because Lord Paget had been the guardian of the heir to the
Willoughby estates. Thomas, whose father Henry Willoughby, had
been killed supporting the Earl of Warwick in putting down Kett's
Rebellion* in Norfolk in 1549, had married Paget's second daughter,
but he died in 1561 while hunting at Middleton; he was then only 18.
On his death his younger brother, Francis, became the heir to the
estates at the age of 12.
Francis was a tragic figure5 desperate to take his place among
the great of the land. He lived beyond his means, contracted perhaps
the worst marriage recorded in the Tudor era, had at least six
daughters, but no son and heir and took on more debt than he could
service. He had inherited the coal mines at Wollaton, which gave
him a significant income, but he needed more to achieve his ambition
of building a house fit for a Queen and appropriate to the status to
which he aspired.
His estate at Middleton shared the problems of infertility
common to the land in the Midlands and appeared to have little to
contribute to his ambitions but he did have the Langley Brook
flowing through the grounds. Water power is rare around
Birmingham. The density of water mills to the east of the town was
about one for every five square miles and the flow of water alone
could not be relied on as it might be in hilly districts. A significant
reservoir was required for each mill.
Footnote
* Some would say that Kett's rebellion was about land enclosures in Norfolk,
perhaps another link between Middleton and the growth of Birmingham
5
Francis must have been aware of Lord Paget's works. He
therefore knew that the requirements for making iron were supplies
of ironstone, charcoal, clay and water power. He had the possibility
of water power, his land could produce the coppiced woodland
needed for charcoal, and clay is available in most places. Three out
of four must have seemed a fair start for him, so he set his steward,
John Tyrer on researching the requirements for building his own
ironworks, as evidenced by a letter dated December 6th 1571 in The
Middleton Collection6. Richard Smith7 believed that a hammer mill
and blast furnace project was started at Middleton around 1577.
There is no reference to the creation of Middleton Pool as the result
of this project but it is most likely that this was when the pool was
enlarged. There was not enough water to complete the manufacture
of iron from a blast furnace, and a second pool was leased at Hints,
about seven miles away.
Figure 4. Part processed bloom found in Middleton Park.
There is clear evidence that the first operation at Middleton
used the obsolescent bloomery hearth process, which is described in
the appendix. For this, water power was not necessary and the part6
processed bloom shown in Figure 4 was found in a place where
water power was not available, on the south side of the pool and
close to the Coleshill to Tamworth road. To make a business in tune
with his ambitions Francis had to progress quickly to the larger scale
operation using a blast furnace. This was located at the outflow from
the pool, where a nine foot head of water has been created by the
dam. The remains of the furnace base are still to be seen today, as
shown in Figure 5.
Figure 5. Remains of the blast furnace beside the Langley Brook.
That this is the location of the furnace can be in no doubt. Firstly its
location is the obvious place, but also because the materials shown in
Figure 6 were all found by the base after a small amount of the
overburden had been removed. They are limestone, iron ore and part
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processed ironstone or slag. There is no limestone or iron ore within
miles of Middleton and they could only be there as a result of an
iron-making operation.
Figure 6. Mineral and slag samples from the base of the blast
furnace shown in Figure 5.
The slag sample shown at the upper left has a significant amount of
metallic iron in it, as shown by the small magnet that is suspended on
a vertical surface.
The creation of the enlarged pool was a major undertaking. It
is formed by a brick-faced earth dam, although the face is now
hidden and it cannot be ascertained that its bricks were laid in the
sixteenth century. The dam is over a hundred yards long. When
built it would have been a simple structure, discharging via a sluice
that contained the mill race. A waterwheel linked to a tilting
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mechanism would have worked the bellows.
The last furnace at Middleton continued in operation until
about 1620, by which time it was no longer controlled by the
Willoughby family. Willoughby also invested in furnaces at
Oakamoor in Staffordshire and Duffield in Derbyshire.
The blacksmiths laid the foundation for Birmingham's
manufacturing achievements, soon becoming the main suppliers of
guns, swords, and housewares. Their success depended on the
supply of iron that was led by Lord Paget and Sir Francis
Willoughby and soon followed by Lord Dudley and others.
Post Industrial Middleton
So many of the beauty spots of today are actually postindustrial. Derbyshire and the Lake District show many traces of
lead and other mineral extraction and valleys in Lancashire and
Yorkshire were thriving wool and cotton locations as the water
power available was used to drive weaving frames and jennies.
Middleton became a post-industrial site earlier than most, mainly
because its industry was ill conceived. Richard Smith's analysis of
Francis Willoughby's venture concludes that he would have done as
well or better by selling his coppiced wood for charcoal production.
As elsewhere, the result of the industry was to change the
environment. The enlargement of the pond into a pool was the most
obvious but access to the Hall was also altered.
There is now a road over the dam, which the first series
Ordnance Survey map shows to have been there early in the
nineteenth century. However, for most of its history, the Hall was
approached from further south along the Coleshill to Tamworth road.
In Figure 3 a track is shown running below the pool. There is no
trace of this today although it must have existed at the start of the
nineteenth century. The evidence now suggests that there was an
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approach to the house along a track between the pool and the local
stream that fed the moat. We can be sure that the Willoughbys and
their visitors would not have entered past the iron works when it was
operating and it is probable that the main entry route only switched
to the road over the dam after John Peel had the deer removed from
the park around 1850. The last tenant of the Lords Middleton,
Egbert de Hamel would have used the road over the dam as he went
to and from his ribbon works in Tamworth on horseback.
Enlarging the pool to create a reservoir brought the water
closer to the Hall and at some stage the moat was connected to the
pool by a link, shown in Figure 4. There is no evidence that the moat
ever again surrounded the house after the section across the front was
filled in during the Tudor era. The first series Ordnance Survey map
shows it round three sides of the Hall.
Figure 7. Plan showing the link from the pool to the moat.
Until the twentieth century it is unlikely that the water around
Middleton was used at all after iron-making ceased, except for
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leisure pursuits, such as fishing, wild-fowling and swimming. After
Percival Willoughby took up residence at Wollaton early in the
seventeenth century, the Hall was used as the family home for his
son, Francis and again in the next generation by the third Francis, the
famous naturalist. They lived on the income from their properties and
from the coal that was mined at Wollaton. A fourth Francis inherited
the estates when Francis the naturalist died at the age of 36, but did
not gain control of his inheritance for a further ten years when he
reached the age of 16. He then chose to live at Wollaton. Wollaton
remained the main Willoughby family home for several generations.
There were significant changes to the buildings at Middleton
when the fourth Francis' brother became the first Lord Middleton in
1713 but these did not affect the pool or the moat.
The Tenancies
The hall was tenanted throughout the nineteenth century. As
far as is known, only one tenant made any significant changes
affecting the water courses. John Peel was a cousin of his neighbour,
Sir Robert Peel. Both men sat as MPs for Tamworth, Sir Robert
more consistently than John. While John was a tenant between about
1850 and his death in1872 he had the deer removed from the park
and he filled in the moat. A photograph (Figure 8) taken by a
member of the Warwickshire Photographic Survey at the end of the
nineteenth century shows the result.
It was during the tenure of the last of the tenants that the
greatest of the events affecting the waters of Middleton occurred. It
was on the last day of the nineteenth century. The twentieth century
truly came in with a bang, quite different from the Millenium Bug
scam that was invented to frighten people and generate revenues for
the parasites in our society at the turn of the twentieth into the twenty
first century. (Companies were required to pay their auditors to carry
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out an audit of their computer systems to ascertain the level of risk.
There was no risk.) Egbert de Hamel wrote “During the great gale
that signalised the last day of the nineteenth century the rush of water
into the lake at Middleton was so strong that it made a clean breach
34 feet expanding to 42 feet wide and six feet deep, through the dam
that carries the carriage drive, the escaping torrent of water being so
powerful as to excavate a hole 12 feet deep below the surface of the
field at the foot of the embankment and to carry large ashlar stones
and masses of the displaced masonry for considerable distances. The
storm resulted in the most disastrous floods all over the country that
have occurred for five and twenty years.” There were no human
casualties at Middleton.
Figure 8. The moat after John Peel.
The location of the breach is shown in Figure 5, where some
of the masonry displaced by the flood is still in evidence. The breach
was limited by the brickwork and the furnace base remaining from
the ironworks and the concrete at the top of the picture gives a good
indication of the extent of the damage. Also seen in the photograph
of Figure 5 are some of the features introduced to try to maintain the
dam after its repair. To the left of the furnace base is a cast iron pipe.
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This was connected to a head gear, shown in an early twentieth
century photograph in Figure 9, which operated a sliding gate valve
and allowed the pool to be drained in order to allow the brick face of
the dam to be kept in good condition.
Figure 9. Along the dam early in the 20th century.
It is probable that this was the only modification to the dam
following the flood of 1899 and the valve may also have been used
for removing silt from the lake, as well as for dam maintenance.
There are now a number of features along the dam, their positions are
marked on Figure 10 below, but these were probably of later
construction. The main outflow is at 1 on the picture.
Egbert de Hamel was the last of the tenants of Lords
Middleton and when he died in 1924 the Middleton estate,
comprising some 3600 acres, was sold to John Averill.
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Middleton Hall's Last Family
Averill was a businessman who worked his estates. He had
farms on the estate and at Bishops Castle, Evesham and in Wales.
These were managed by employees, not rented out. Averill also had
a brickworks in Tamworth. At Middleton he sold the water lilies
from the pool, which can be seen to be abundant in the photograph of
Figure 9. They were used in London and Manchester hotels as table
decoration and were in demand in Manchester for Jewish funerals.
There are still people in Middleton village who recall going to the
Hall to help with collecting the blooms from flat bottomed boats.
They were then packed and taken to Tamworth station for carriage to
their customers.
Figure 10. Features of the pool,
We know from the reminiscences of the last survivor of
Averill's children that the pool was never very deep. The family
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would swim in the only deep part, which was near the entrance to the
link to the moat (3 in Figure 10). However there was enough water
flowing through it for the original purpose of the reservoir, the
provision of power, to be revived in more modern form. A water
wheel was installed to drive a dynamo that was used to bring electric
power to the Hall. In Figure 11 the building (at 4 in Figure 10) that
housed the waterwheel is shown.
Figure 11. The Pump-house in 2001.
Until 2001 nobody at Middleton knew that this building
existed. It was completely covered in brambles, ivy and hawthorn
scrub. When this was cleared the inside of the structure was full of
silt and the stream from the wheel had been filled in. The picture
shows what it was like after much hard work and before the building
was repaired. The structure suggests that the section at the right was
added after the main part, which housed the water wheel. This is
confirmed by the discovery of a ram-pump in a rough hole in the
wall between the two parts. This is shown in Figure 12.
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Figure 12. The Ram Pump.
As found the ram pump was buried in and full of silt, but the
nuts holding it together were brass, so it was possible to get them off
and dismantle and clean it. It only needed the replacement of the
gaskets and valves for the pump to made workable. To get it to work
a water supply had to be arranged. A ram pump is supplied with
water from a tank and further clearance of the back of the dam
revealed the original brick tank. Its connection to the pool was full
of silt and had to be cleaned, but once this was done and the tank was
cleaned out the supply to the pump could be restored. The delivery
pipe was still there and the pump was got working.
A ram pump is a controlled water-hammer which is able to
raise to a great height a small amount of the water that falls a few
feet from the supplying tank. At Middleton the pump was originally
used to supply water to the Walled Garden. This it did through a
pipe that crossed the end of the pool and entered the garden, used at
that time as a market garden, close to the gazebo, a distance of over
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100 yards. The pipe to the garden was no longer complete when the
pump was restored so a small tank was placed on top of the pumphouse to provide an outlet for the pump.
There are three different types of conventional water wheel:
under-shot, where the water in a stream pushes flat vanes projecting
from the perimeter as it passes below the wheel; over-shot, where a
chute delivers the water to the top of the wheel, filling bucket shapes
vanes, the weight of water turning the wheel forward, and back-shot.
The back-shot type is the most efficient and the Middleton wheel was
of this type. In the back-shot configuration the chute delivers the
water just before the top of the wheel, filling buckets, the weight of
which turns the wheel backwards. The wheel is placed against a wall
that curves around the lower quadrant of the wheel, so that the water
cannot escape until it passes out beneath the wheel. The shape of the
wall in the pump-house fits a wheel of 5 feet diameter. Sadly the
wheel no longer existed. Nor did the dynamo, although a beam at
about six feet from the floor still has the fixings that would have
attached the dynamo.
The water supply to the wheel entered the pump-house
through the back wall and it is said that it connected to a long curved
pipe of large diameter with a bell mouth that took water from just
below the surface in the middle of the lake. This no longer exists.
The electricity delivered to the house would have been no
more than a few hundred watts, probably carried-in having been
stored in lead acid accumulators. It could only have provided
lighting and the radio; cooking would have been on coal or wood
fired ranges until mains electricity arrived after World War 2.
At 5 in Figure 10 is another conduit that passed through the
dam, shown in Figure 13. It does not allow water through it now but
it was evidently installed for a purpose. When it was is built is not
clear but the presence of blue brick, which would have been
17
manufactured by John Averill's factory in Tamworth, suggests that it
was after 1925. In 2002 John and Richard Averill, grandsons of John
Averill, who had lived at the Hall when they were boys, were visitors
to the Hall. They recounted how they had the job of occasionally desilting the pool through this channel. They could only have kept a
small area of the pool free of silt, so it is possible that it was
associated with keeping the swimming area available.
Figure 13. Brick culvert through the dam.
A number of other features were introduced during Averill's
ownership of the property. These were almost certainly introduced
following the first legislation to deal with reservoir safety, which was
passed in 1930 following a number of disasters. The most significant
was the overflow provision, which as located at 2 in Figure10. The
map shown in Figure 3 suggests that there may have three small
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streams below the dam. The one furthest north, at 2 in Figure 10, is
where an overflow culvert has been installed. It is of a poorly
designed letterbox form that acts to introduce turbulence in the
emergent flow that has the effect of under-scouring the back of the
dam when the stream is in flood as may be inferred from Figure 14.
Figure 14. Overflow sluice in flood.
Another feature probably introduced by Averill is shown in Figure
15. It is located a little north of the pump-house and its function is
unclear. It is a tank about five feet deep with a feature above it, seen
here as a row of bricks, which is the edge of a covering slab that had
been placed over what was almost certainly a valve chamber. From
this chamber a culvert passed under the road to the pool and a 12”
pipe descended into the tank. Another 12” pipe provides an outlet
from the tank and continues for several yards until running out into a
stream below the main Langley Brook that feeds into a fish pond.
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Figure 15. Tank below the dam, possibly a fish trap.
One conjecture is that the tank is a sort of fish trap that prevents
undesirable species getting into a pool where fish for the table were
reared. The tank had been covered by some wooden beams that had
rotted and become overgrown with brambles. It was discovered
when a volunteer's foot went through an unseen hole.
No Longer a Home
Frederick (Dick) the son of John Averill had another house near
Burton-on-Trent and was not at Middleton much after he inherited
the Hall in 1948. He sold it in 1966 to the Amey Roadstone
Corporation along with the parts of the estate that lie along the Tame
Valley. One of the fishermen that has fished the pool for many years
told that Amey blew up the pipe that supplied water to the pumphouse, laid a membrane over the face of the dam and vastly
strengthened the dam by loading its face with large silica cobbles.
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The quarrymen call these cobbles 'duckers', they are the material
yield of gravel extraction that is too large in size to be crushed. The
purpose of facing the dam with them was obviously to deal with the
implications of successive Acts of Parliament relating to the safety of
Reservoirs and to obviate the need to maintain the brick face of the
dam. This dam will not fail under the impact of a major storm,
provided that the back of the dam is maintained.
The progressive silting-up of the pool has been accelerated by
two major events. Firstly the planners allowed the farmer on the
other side of the A4091 to dig a fishing pool beside the Langley
Brook. The displacement of earth in such a major excavation cannot
have failed to add to the material carried downstream. Secondly the
line of the M6 Toll crosses both the Langley Brook and its tributary,
Colletts Brook. It was not until the Middleton Pool became red with
the sand that the roadworks displaced and the Trust lodged a
complaint that the road builders created settlement ponds along the
line of the road. It is one of the idiocies of the planning system, or
lack of it, that there was no protection built-in against the
consequences of these works on waters, like this one, which is a
protected water and an SSSI. The protected status mean that foreign
species cannot be introduced into the water, but nothing prevents the
fish-pond higher up the stream from being stocked to jeopardise the
pool's indigenous population.
Silting has now reduced the deepest part of the pool to about
2 ft. The surface area of the pool has significantly reduced and much
of the flow into it is through a wet woodland. The banking of the
front of the dam deflects any surge so that it overtops the dam at the
lowest point, which results in the water overflowing the dam, where
it is strengthened by the pump house and is at its widest. The
resultant flow is then away from the only habitation nearby, which is
New House Farm. There will be no recurrence of the excitement of
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the last day of the nineteenth century, when the dam was burst by the
volume of water that came straight down the Langley Brook, hitting
the weakest part of the dam head-on.
Amey also created a major change in the view from
Middleton Hall (Figure 16) by extracting gravel almost right up to
the south wall of the Hall. The South Pool is not fed by any stream,
it is a water-table pool that has occasional wildfowl on it and is often
invaded by an unpleasant red algae.
Figure 16. View from the South Wing of the Hall
The only other consequence of the acquisition by Amey, who
had no interest in the Hall itself, was to create a water course along
the line of the moat to deliver a supply to the gravel workings below.
This was a bodged job. Visitors like to call the water course a moat.
It does not qualify on any reasonable grounds for that description. It
would provide no hindrance to invaders and it is not ornamental.
The water has to be at least 4 ft deep if there is to be any hope of
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controlling infestation by reeds, but Amey simply scooped out
enough earth along the line of the former moat to deliver the water to
a sink hole at the south east corner of the property. This feeds into a
stream and a series of narrow pools that continue down the slope
towards the valley to the quarry. It is a major problem for the Trust
to keep it running.
Ecology
As a Site of Special Scientific Interest, the grounds in which
Middleton Pool lie depend to a large extent on the fact that the
Langley Brook is one of the cleanest streams near to the Birmingham
conurbation. There are English (white clawed) crayfish, grasssnakes, newts, swan mussels and several varieties of water-snails as
well as a good cross-section of coarse fish, including pike, in the
pool. There were carp, but all have been removed by the fishing club
that uses the pool to another of the local pools.
Figure 17. Left – white clawed crayfish. Right – grass-snake.
The flora include king-cups and water lilies, although the progressive
silting has reduced the, once abundant, population of lilies(Figure 9)
to a few stragglers. There are several varieties of reed and horsetail
as well as watercress and irises.
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Figure 18. Left – Kingcups, Right – Water Lily
Above the water the damselflies and dragonflies are abundant in their
season and the pond dipping for various water bugs is a common
feature of the open days when children's pursuits are the main
attraction.
120 species of bird have been observed on or over the water
of the pool, but in recent times this number has reduced as the silting
of the pool has made it unattractive to many of the diving birds. Of
the divers only coots and great crested and little grebes frequent the
pool. There has been no compensating increase in the variety of
wading birds although the common species are more often seen as
the silt banks create new feeding grounds for them. A pair of swans
reared cygnets every year of the Trust's first 29 years until the cob
was killed by a vandals pellet through its eye. The widowed pen
took her young to the back pool and the main pool was immediately
colonised by a new pair.
The creation of the RSPB's Middleton Lakes reserve next
door will eventually attract a wider variety of species and maintain
the interest in the study of the science of ornithology that was started
around 1660 at Middleton.
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Appendix
Ironmaking Processes
The first iron-making at Middleton in about 1575 used the
already obsolescent bloomery hearth process. In this process iron
oxide was heated with charcoal to produce iron mixed with
impurities, mostly sandy material in this area. The iron made this
way was never molten; it was subsequently heated and hammered to
squeeze out some of the impurities and formed into billets or bars to
be sold to blacksmiths for horse shoes, farm tools, swords and guns.
All of the processes were carried out manually. The materials
required are iron ore, charcoal and clay to make the furnace. No
water power was needed; the bellows to make the fire hot would
have been hand operated.
Figure A1. Schematic of a bloomery hearth.
As can be seen from Figure 5 the bloomery hearth is a simple
structure. It is made of clay. In operation, kindling was used to light
a fire, charcoal was then introduced as a fuel and it was topped off by
a mixture of ironstone and charcoal. At a temperature anywhere up
to 1000C the carbon reacts with the ironstone to leave a mixture of
iron with the extraneous impurities.
To achieve the high
25
temperatures needed, the fire was driven using manual bellows via
the blowhole. The lable 'tapping arch' wrongly implies that the iron
flowed out. It would have been blocked with bricks that were
removed at the end of the process, when the metallic mass would be
pulled out. This feature was often not used. The metal was then
taken out of the mouth of the furnace
Figure A2 Illustrating the blast furnace configuration (left) and
location (right)
Some time before 1590 the operation was upgraded to use the
blast furnace. This technology had been available for almost a
hundred years. It is much like a bigger bloomery hearth furnace that
uses a forced draught to achieve temperatures high enough to melt
the iron. It is probable that it was to develop the power for this
process that the stew pond was enlarged to act as a reservoir from
which water power could be taken to operate the bellows. The
schematic diagram in Figure A2 is a more modern design than would
have existed at Middleton, but the principle is the same. On the right
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hand side of the picture, taken from the Wealden Iron research
Group's web-site (http://www.wealdeniron.org.uk/) the configuration
used in the Weald of Kent and Sussex is shown. It almost perfectly
replicates the layout at Middleton.
Blast furnace operation requires one additional raw material,
limestone. This was not available at Middleton, so had to be brought
by horse or ox drawn cart from Derbyshire. In the heat of the
furnace the lime reacts with siliceous materials to make a fluid that
floats on top of the metallic iron and is easy to separate. This is an
important advantage of the higher temperatures, since iron containing
silicate particles is poor stuff. (Bloomery hearth produced iron
would have been better if produced from a lime containing iron ore).
A disadvantage of the blast furnace process is that the iron
absorbs carbon from the charcoal. This has two important effects. It
lowers the melting temperature of the iron and it is therefore easier to
achieve the molten state but the iron produced is very brittle and
cannot be worked into swords and other tools. As a result the
manufacture of the iron required by the Birmingham smiths had to
use additional processes to remove the carbon. The finery in which
the carbon was removed consisted of a furnace in which the iron
billets were heated with mill scale, that is iron oxide that has fallen
off the heated billets during forging. The hot billets were repeatedly
heated and hammered so that the iron oxide could react with the
carbon containing iron to reduce the level of residual carbon. To
carry out this operation a further source of water power was needed.
The lack of water power in the Midlands led in the Middleton case to
a second water wheel being used at Hints about seven miles away,
requiring the cast iron sows to be transported 7 miles there and the
resultant billets 7 miles back. A billet found behind the Tudor Stables
at Middleton indicates that the stockyard was there.
The Middleton iron works was unique at that time being the
27
only place at which iron was produced where there was no ironstone.
Initially the ironstone supply came from the Staffordshire sources
controlled by Lord Paget, who doubtless profited most from
Willoughby's venture. Later a supply was found in Warwickshire,
near to Polesworth, but the transport costs would have resulted in the
operation being very marginal at best. This situation was not
improved when the second site at Hints was leased to carry out the
finery hearth and chafery hearth processes.
References
1
VCH Warwickshire vol 4 (http://www.british­
history.ac.uk/report.aspx?compid=42672)
2
Hodder M. Transactions of the Birmingham Archaeological Society 97,(1988),41­56.
3
Chandler J. “John Leland's Itinerary: Travels in Tudor England” Stroud:Alan Sutton, (1993)
4
Pelham R.A., Univ of Birmingham Hist. J.,IV (1953­54),18­
29
5
Middleton Hall Booklet., MHI­03. “The First Francis Willoughby”.
6
HMC Middleton MSS p 494
7
Smith R.S., Renaissance and Modern Studies, 11 (1967), 90 – 140.
8
de Hamel E. Transactions of the Birmingham Archaeological
Society, 27, (1901), 16-28.
28