Mill
Operation
Grain would arrive at Lyneham mill by horse and cart in sacks
from the surrounding farms or the local estate. In dry summer
harvest weather, carts were often drenched in the water to
allow the dry wooden wheels to tighten by swelling as they
got wet. Lilybrook stream provided the water to power the
mill paddle. To ensure adequate water supplies were available
all seasons, the stram water was routed to the Mill Pond,
which acted as a reservoir or accumulator of water. Sluice
gates were controlled to allow adequate volumes of water to
turn the wheel.
The sacks of grain had to be taken up to the top floor and
this was done by the "sack-hoist". Its chain was
lowered from the locum that projected out from the top of
the mill. The sack hoist was operated by a series of pulleys
and gears powered by the waterwheel.
Once at the top, the grain was emptied into either a "hopper"
or a "bin". The bins were used for storage and the
hoppers (on the second floor) for feeding the grain to the
millstones. The grain fell through chutes from the hopper
into a smaller hopper on top of the stones (on the first floor)
from where it would be guided into the centre of the stones
by the "slipper." a moveable wooden chute. The slipper
was agitated constantly to ensure a smooth flow of grain into
the stones. This was done by the "damsel" (the four-armed
shaft projecting up from the centre of the stone)- so called
because of the constant chattering it made against the slipper!
Many mills had an arrangement whereby the front doors opened
on two levels. The carter unloaded sacks from the top of the
cart straight into the first floor of the mill and the cart
became emptier, the lower sacks were then unloaded into the
ground floor.
Mills usually had between two and five pairs of stones, which
were encased in wooden "tuns". Stones were of two
types, each for a different application. Derbyshire Peak grit
stones wore down fairly quickly and were only fit for grinding
animal feed as they left stone dust in the ground product.
French burr stones were the best quality and were almost exclusively
used for grinding wheat into flour because they contained
crystals of very hard quartz. These crystals created sharp
grinding edges that did not chip into the flour and the stones
needed less frequent sharpening ("dressing"). French
burr stones came from only one quarry just outside Paris and
were only found in small pieces - none big enough to make
a complete millstone - so each stone was made of several skilfully
shaped pieces held together with plaster of Paris and an iron
ring heat-shrunk around the outside of the stone.
Each of the stones is divided into sections called "harps".
The harps have a complex grinding face cut into them consisting
of "lands" (the raised sections) and "furrows"
(the grooves) which had to be dressed regularly using a "mill-bill"
and a good eye! Once the lands were properly flattened during
the dressing process. they had to be "stitched".
This required up to 12 fine lines per inch to give the best
grinding surface for white flour.
When the stones were together as a pair they had to be perfectly
balanced, perfectly level, and precisely the right distance
apart - the thickness of a piece of brown paper at the centre
of the stone and of a piece of tissue paper at the circumference.
This gap was adjusted by a process called "tentering;"
the top stone could be lifted on the "spindle" by
a turn-screw on the ground floor.
Only the top stone ("runner-stone") rotates in
any pair, with the "bedstone" fixed to the floor.
The runner-stone is balanced above the bedstone, hanging on
the "mace" (or "rynd") which is supported
on the spindle. When the grain falls into the centre of the
runner-stone it is forced outwards by the pattern on the surface
of the stones and the action of centrifugal force. It is crushed
between the lands and falls from the edge of the stone as
flour. The flour passes down a chute where it can be bagged
on the ground floor as 100% wholemeal flour.
White flour is produced by a machine called a wire-machine
or "bolter". A series of sieves, made from finer
and finer mesh are used to separate the 100% flour into bran,
semolina, and white flour.
All the power for the mill stones and auxiliary machinery
was provided by the waterwheel. There are three types of waterwheel,
overshot, breastshot and undershot. An overshot wheel is powered
by the weight of the water falling over the top of the wheel
into buckets. With a breastshot wheel, the water enters the
buckets level with the axle and the wheel produces only about
one third of the power of an overshot wheel. The third type
of waterwheel is undershot, where the water passes under the
wheel; it is the force of the water hitting the paddles that
turns the wheel rather than the weight of water in buckets.
The majority of mills in Wiltshire are either breastshot or
undershot, mainly because the terrain is no more than undulating
and does not provide the high head of water required by an
overshot wheel.
An overshot wheel needs a head of water that can only be
provided by artificially raising a river. This would require
the building of a "leat" the diversion of the river
along the side of a valley, until a sufficient height of water
had been reached to work the waterwheel. This was a huge feat
of engineering considering the mass of soil used to construct
the river banks and the similar mass of clay and chalk used
to waterproof the bed of the river; remarkably built by hand.
The water was built up and stored by closing the two sluices
to stop the water flowing downstream. The water would fill
the "launder" (or "pentrough") above the
wheel which could then be opened to turn the machinery. Alternatively,
if the river filled too much the sluices could be opened to
allow the water downstream without turning the wheel.
A waterwheel rotates at about 10 revolutions per minute (r.p.m.)
and the power is then transmitted through the wheel-shaft
to the "pit-wheel" in the hurst frame. The pit-wheel
drives a smaller "wallower" which in turn drives
through the "crown-wheel" and "pinion",
along the main horizontal lay-shaft to the "stone-nuts."
Each stone-nut is attached to a stone "spindle"
which drives the runner stone. By this stage the gears have
increased the speed of revolution from 10 r.p.m. at the wheel
to about 120 r.p.m. at the runner-stone.
The Decline Of Village Mills
Until the mid-19th century, many villages had wind or watermills
to grind flour for the community. Before Henry VIII's dissolution
of the monasteries in the mid-fifteenth century, most mills
were owned either by the Church or by the Lord of the Manor.
Milling rights were jealously guarded, and villagers would
have been allowed to grind corn only at their landlord's mill.
The law at that time required flour to be ground only at your
Lord's mill - known as his "Right of Soke". The
miller charged up to 10% of the grain, and the landlord frequently
took a further cut.
At that time bread made with flour from English wheat was
very different to that which we know today; it was very much
heavier and little risen. The best milling wheat would later
come from America where, because of the climate, the grain
was harder and produced a stronger flour (containing a higher
proportion of gluten).
After the repeal of the corn laws in 1846, plentiful supplies
of American wheat became available. This gave a significant
advantage to mills based near the major seaports. At about
the same time, a more efficient milling process was invented
in Germany; in this the grain was crushed between two steel
rollers, rather than ground between millstones.
By the mid to late nineteenth century, many of the old watermills
and even windmills were adding steam, gas or oil engines in
an attempt to compete with their modern counterparts. They
could not survive however against this early form of mass
production and by the beginning of the twentieth century most
were reduced to the grist milling of animal foodstuffs.
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