Water mills have been around since Roman times in the uk. Over 5,000 were listed in the doomsday book.
In common with all machines they were constantly rebuilt and altered over their working lives as parts wore out and technology advanced, such that much of the mills that are left today represent a patchwork of the mills and local social history.
Most mills that are left have a history dating back to the doomsday as sites tend to be reused over and over again.
There are three basic types of water wheel, the overshot, the undershot and the breastshot. the over shot is the most efficient followed by breast and lastly the under shot. most remaining wheels fit into one of these categories.
Overshot
In the overshot the water enters at around 12 oclock (top of the wheel) and it uses the water's weight in trough shaped buckets around the wheels rim to rotate the wheel. It would use little water for a high out put but requires a large head (fall in water levels) to operate. a good example of an overshot wheel is the wheel mill at the Weald and Downland museum in Sussex. such wheels can be up to 90% efficient.
Undershot
The earliest development of the water wheel is the undershot wheel, in this case the flow of the water strikes flattened boards or paddles and turns the wheel. The wheel requires a very low head to rotate but is very inefficient. It was widely used in larger rivers such as the Thames, Severn or Avon where high flow and low fall was available. Later developments in design by a French man named Poncelot increased efficiencies by improving hydrodynamics and water flow onto and from the buckets. Even then the wheel was generally under 50% efficient.
Breast shot
Breast shot wheels are a compromise between the two designs using curved buckets, the water usually enters around axle level with the water flowing under the wheel not over it. They are quite common and relatively efficient. Some of the earliest cotton mills used this type of wheel in gigantic proportions being 18 feet diameter and 23 feet wide! A good remaining example is left at quarry bank mill Styal and develops several hundred horsepower. The final development of the water wheel was the turbine. There are many different variations of turbine but are generally beyond the scope of this here as most corn mills rely on older technology. We have however been involved in mini-hydro projects and are happy to discuss any requirements for installation/ electricity generation. Water power is making a researgence in the C21st. with over 40 small scale micro power sites up and running on some of the 40,000 possible former mill sites in the uk.
Windmills
There are three main types of windmill in the UK. The earliest development dating back to the 12th century is the post mill. The post mill is so called because the whole mill is balanced on a post allowing the mill to face into the wind (something all windmills must be able to do). the mill is frequently depicted in psalters and church carving from the time and has changed little in the remaining 800 years. The last postmill built in the uk was in kent in 1863. post mills were limited in size and relatively frail as they regularly blew over. postmills were wooden structures so without maintenance quickly disintergrated there are less than 50 left in the uk today.
The Tower mill was a later development in which the machinery was housed in a more durable masonary or wooden tower (smock) and the cap (top) rotated on a bearing to allow the sails to face the oncoming wind. this was the pinacle of windmill development in the uk with automatic turning devices such as the fantail and multi sails being used in East Anglia and East Midlands.
As can be seen left, (Pakenham mill) the large "vane" on the rear of the mill is the fantail which keeps the mill into the eye of the wind and the patent sails in the open posistion. The advantages of masonary towers meant that mills could be built larger and with heavier caps. The tower was less suceptable to the weather and although frequently tarred to keep out the weather couldn't get blown over like a pot mill.
The smock mill was a deviation of the tower mill and was generally built on the south eastern areas of the UK, mainly Sussex, Essex, Suffolk, Surrey and Kent, though they did exist in other counties they were seen as a cheaper and more portable tower mill. there were many instances of mills (both post and smock types) being dismantled and moved either with the body or buck (if a post mill) intact pulled on a large trolley by horses or oxen. The windmill at Terling in Essex was a good example of this. It was moved by sawing down the cant posts (main structural timbers in the corners of the octagon) and moving the floors and side pannels and bolting it all back together as you would a modern flatpack shed. its this moving of the mill which caused terlings eventual demise as the octagonal cone twisted like a helix and jammed the curb (bearing that the cap rotates on). The windmills heyday was over by the late C19th. and the last complete mill was built in 1895. the advent of the internal combustion engine and small metal mills for animal feeds coupled with food hygene acts meant that commercial flour was impossible so pig feeds kept most of the remainder going. some well into the 1970s!
Again as with water power wind power is making a come back with windfarms and turbines springing up in many areas of the uk, often contraversial due to their visual impact they provide a modern take on an old problem harnessing the fickle wind.
In common with all machines they were constantly rebuilt and altered over their working lives as parts wore out and technology advanced, such that much of the mills that are left today represent a patchwork of the mills and local social history.
Most mills that are left have a history dating back to the doomsday as sites tend to be reused over and over again.
There are three basic types of water wheel, the overshot, the undershot and the breastshot. the over shot is the most efficient followed by breast and lastly the under shot. most remaining wheels fit into one of these categories.
Overshot
In the overshot the water enters at around 12 oclock (top of the wheel) and it uses the water's weight in trough shaped buckets around the wheels rim to rotate the wheel. It would use little water for a high out put but requires a large head (fall in water levels) to operate. a good example of an overshot wheel is the wheel mill at the Weald and Downland museum in Sussex. such wheels can be up to 90% efficient.
Undershot
The earliest development of the water wheel is the undershot wheel, in this case the flow of the water strikes flattened boards or paddles and turns the wheel. The wheel requires a very low head to rotate but is very inefficient. It was widely used in larger rivers such as the Thames, Severn or Avon where high flow and low fall was available. Later developments in design by a French man named Poncelot increased efficiencies by improving hydrodynamics and water flow onto and from the buckets. Even then the wheel was generally under 50% efficient.
Breast shot
Breast shot wheels are a compromise between the two designs using curved buckets, the water usually enters around axle level with the water flowing under the wheel not over it. They are quite common and relatively efficient. Some of the earliest cotton mills used this type of wheel in gigantic proportions being 18 feet diameter and 23 feet wide! A good remaining example is left at quarry bank mill Styal and develops several hundred horsepower. The final development of the water wheel was the turbine. There are many different variations of turbine but are generally beyond the scope of this here as most corn mills rely on older technology. We have however been involved in mini-hydro projects and are happy to discuss any requirements for installation/ electricity generation. Water power is making a researgence in the C21st. with over 40 small scale micro power sites up and running on some of the 40,000 possible former mill sites in the uk.
Windmills
There are three main types of windmill in the UK. The earliest development dating back to the 12th century is the post mill. The post mill is so called because the whole mill is balanced on a post allowing the mill to face into the wind (something all windmills must be able to do). the mill is frequently depicted in psalters and church carving from the time and has changed little in the remaining 800 years. The last postmill built in the uk was in kent in 1863. post mills were limited in size and relatively frail as they regularly blew over. postmills were wooden structures so without maintenance quickly disintergrated there are less than 50 left in the uk today.
The Tower mill was a later development in which the machinery was housed in a more durable masonary or wooden tower (smock) and the cap (top) rotated on a bearing to allow the sails to face the oncoming wind. this was the pinacle of windmill development in the uk with automatic turning devices such as the fantail and multi sails being used in East Anglia and East Midlands.
As can be seen left, (Pakenham mill) the large "vane" on the rear of the mill is the fantail which keeps the mill into the eye of the wind and the patent sails in the open posistion. The advantages of masonary towers meant that mills could be built larger and with heavier caps. The tower was less suceptable to the weather and although frequently tarred to keep out the weather couldn't get blown over like a pot mill.
The smock mill was a deviation of the tower mill and was generally built on the south eastern areas of the UK, mainly Sussex, Essex, Suffolk, Surrey and Kent, though they did exist in other counties they were seen as a cheaper and more portable tower mill. there were many instances of mills (both post and smock types) being dismantled and moved either with the body or buck (if a post mill) intact pulled on a large trolley by horses or oxen. The windmill at Terling in Essex was a good example of this. It was moved by sawing down the cant posts (main structural timbers in the corners of the octagon) and moving the floors and side pannels and bolting it all back together as you would a modern flatpack shed. its this moving of the mill which caused terlings eventual demise as the octagonal cone twisted like a helix and jammed the curb (bearing that the cap rotates on). The windmills heyday was over by the late C19th. and the last complete mill was built in 1895. the advent of the internal combustion engine and small metal mills for animal feeds coupled with food hygene acts meant that commercial flour was impossible so pig feeds kept most of the remainder going. some well into the 1970s!
Again as with water power wind power is making a come back with windfarms and turbines springing up in many areas of the uk, often contraversial due to their visual impact they provide a modern take on an old problem harnessing the fickle wind.