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Technical descriptions of English windmills




Post mill, standing today


One of four surviving Midland post mills, and typical of the Leicestershire/Nottinghamshire region, Kibworth mill is of considerable age, the main post bearing the inscription “Daniel Hutchinson Miller 1711”. Whether or not this was the date of its erection, it is known there was a mill on the site in 1635(1). The present mill exhibits many dates and graffiti from the eighteenth century and later, and there are a number of empty mortices in the timbers. The fabric of the structure is largely original. It retains the wide weatherboarding found on many old post mills, with an outer layer of thinner boards added during twentieth-century repairs. Last worked during the First World War, it was restored in 1936 and is now owned by the Society for the Protection of Ancient Buildings having previously been the property of Merton College, Oxford. At the time of writing further repairs are envisaged during which the buck will be painted white as it was during the mill’s working life.

 The mill is a small one, with a boxlike body standing above a cylindrical single-storey brick roundhouse. The buck is fairly long in relation to its height; it was extended at some point to accommodate the dresser in the tail of the bin/stone floor. It has just two floors, a combined bin and spout floor (it appears that in fact there were no bins, the grain being emptied directly into the hoppers) and the spout floor. There are two very small windows, one on each side, high up on both floors; they are little more than openings in the boarding/framing, in the shape of rounded arches. There is an absence of diagonals in the framing, as with most other Midland post mills. Lower side girts, extending to the main corner posts, are fitted. The front corner posts are of gunstock head type.

 I did not carry out a complete examination of the framing during my visit to the mill in 2012. The spout floor left side framing contains eight uprights with the last between the main and extension corner posts, the others being broken by the lower side girt. The fifth upright terminates at the window. There are four uprights in the breast framing on this floor, the middle two flanking the prick post. The front side rail is raised above the floor. One corner post has a noticeable rebate in it.

The original tailpole remains, now much gnarled with age and partly sheeted with metal.

 Again like other Midland post mills this one turns on a curb, here of wood, on top of the roundhouse walls, with a skirt over it depending from the roof which is attached to the underside of the buck. The main corner posts, the lower ends of which are shaped, protrude down into the roundhouse. The crosstrees, which have rebates in their upper faces near the post, are set low. The piers partly protrude through the roundhouse wall. The ends of the sheers are propped with steel rods from the roundhouse floor and the mill cannot turn to wind. One of the quarterbars is plated with wood to reinforce it. Lying on the floor is what looks like part of an iron gearwheel, with the arms arranged in swastika fashion, while a badly worn millstone leans against the wall.

 A painting done in the 1860s shows the mill with two spring and two common sails. The springs had been replaced with commons by 1913, as shown in a sketch of that date, but one pair was converted back to springs subsequently.(2) It is in this form that the sails have been restored, the spring pair without shutters. They are carried in an iron poll end on a nicely shaped wooden windshaft.


The wooden clasp-arm brakewheel has an iron cog ring fitted. The brake lever appears to be missing but the iron brake band remains. The sack hoist, consisting of a solid wood disc and wood bollard, was apparently driven, by friction, both from the lower edge of the brakewheel rim and the upper edge of that of the tailwheel. The sprattle beam is connected to a pair of roof timbers by two vertical members between which is a hinged timber carrying the bearing for the sack hoist bollard, the whole forming the hoist support frame. The hoist is moved into/out of engagement with the brakewheel (and presumably the tailwheel) by pulling on a rope attached to the timber.

 The tailwheel is a very old wooden clasp-arm, again with iron cog ring bolted on. On the right looking towards the tail it meshes with a four-armed iron mortice gear on a long horizontal shaft, which is square and of iron, going down the side of the mill to near the brakewheel where it terminates in a large solid wood gear the cogs of which have been sawn off. This would have driven a now vanished machine on the spout floor through a second, vertical shaft which has likewise disappeared. On the other side an extension of the teeth of the tailwheel cog ring beyond the rim drives the dresser behind it through a system of shafts and gears which is obviously of late date. The first stage is a four-armed iron mortice bevel nut on a short iron layshaft ending in another four-arm bevel gear, again iron mortice, meshing with a third bevel nut on a vertical iron shaft. At the lower end of the latter shaft a further four-arm iron mortice bevel gear engages an all-iron nut on the dresser spindle.

 Two pairs of stones are driven, one in the head and one in the tail, through iron mortice nuts. The head pair are complete with furniture but the tail pair are missing horse, hopper etc. and the vat has been partly removed to expose the runner. The quant is askew.  

The sack trap is on the right.


The ladder is on the left side to the rear of the crowntree. There is a spout on the right just forward of the crowntree, going to the wall.

 The governors are mounted on the stone spindle extensions, another Midlands feature. The bridgetrees run fore-and-aft; they form T-shapes with the brayers which are at right angles to them. The head brayer is mounted between the two vertical members of the breast framing which flank the prick post. At the other end the bridgetree depends from a hanger from a joist abutting the front side face of the crowntree. The steelyard goes diagonally from a link on the left end of brayer to the governor. At the “north” end the hanger for the tail bridgetree depends from a joist behind but not abutting the crowntree. At the “south” end the brayer is on hangers from a ceiling beam. The steelyard goes diagonally to the governor from the link on the right end of the brayer.  

Visit to mill by G Blythman was on 30th September 2012.

(1) Nigel Moon, Windmills Of Leicestershire And Rutland (Sycamore Press 1981)

(2) Ibid


Tower mill, standing today


One of the four windmills remaining in a complete state, more or less, in the county of Leicestershire, this was built in 1800 as a subscription mill and ceased work probably by 1895(1). Fortunately it remained in fairly good condition and was eventually purchased by John Goodacre, the present owner, who has carried out repairs as necessary to ensure that it stays sound and weatherproof. It is open to the public on certain days during the year, or by appointment. Hopefully it can be restored to full working order one day, if the funds become available.

 The 60ft(2), six-storey red brick tower has a steep batter. There was formerly a stage at second-floor, with the footings for the diagonal supports at first-floor, level but this has now gone apart from one of the supports which survives in the roof of the granary at the rear of the mill, the latter enclosing it(3). The cap is the last remaining example of a type that was characteristic of some mills in the county; low and flat and in the shape of a rounded cone, with a short finial. It was clad in iron sheeting in 1867, which helped to protect the interior timberwork and machinery, and more recently this covering has been replaced with a rubber solution. As is usual practice in the East Midlands/Lincolnshire region the weather beam or rode balk is exposed. No photograph of the mill in working order survives, but it is thought to have had two common and two spring sails; never patents, as the windshaft has not been bored for a striking rod. The fantail has gone and the timbers of its supporting structure have been sawn off short, but within the cap part of the winding mechanism remains; a worm on an inclined iron shaft engages the upper of two iron gears on a vertical shaft, the lower gear meshing with the internal rack.

The curb is live. The truck wheels are carried in large wooden shoes.

 The clasp-arm all-wood brakewheel is mounted on a square iron boss, with eight short arms, cast integral with the iron windshaft. The bevelled all-wood wallower has a friction ring for the sack hoist. Some of its cogs have been cut right through horizontally, for what reason is not apparent.

 It will be noted that the shafts and gears of the largely wooden machinery are particularly massive; it looks like someone wanted to make a good job of it. The substantial upright shaft, circular in section, is strengthened with four iron hoops at top and bottom.


There is a window on the north side. The ladder to the dust floor is on the southeast next to the stairwell. About three-quarters of the floor is taken up by bins: the remaining quarter, the southeastern, is floor space plus the ladder and stairwell. The upright shaft descends through an opening in the partition between two of the bins. 


There are windows on the north and northeast sides.  

The upright shaft terminates in a large raised wooden beam in the floor, the overall impression recalling the arrangement in a watermill. The beam has been cut off short to allow the third pair of stones to be installed, necessitating the insertion of additional supports underneath it(4). The great spur wheel is another substantial all-wood affair, with clasp arms rebated in order to grip the rim. 

 Three pairs of stones on the northwest, northeast and southeast sides are overdriven through solid all-wood stone nuts on square quants. One nut and quant lies displaced on the floor. On the north side a fourth nut on a wooden secondary upright shaft took the drive to the sifter on the spout floor (though Moon says it was the steam drive), at which point the shaft, which terminates in the ceiling of the first floor, changes to iron. All the nuts are massive, the largest I have ever seen on an English windmill. On the north and south sides the wall is stepped inwards, for what reason is not clear.  


There is a single window on the north side. The ladder and stairwell are on the southeast. There is a loading door on the west side.

 A pair of horizontal timbers span the floor east-west and the bridgetrees for two pairs of stones are mounted between vertical posts which are footed in the floor with the upper ends tenoned into the horizontal beams, forming H-shapes. The bridgetree for the third pair is off the northern horizontal timber, at a right angle to the other two bridgetrees, with a brayer at the other end with which it forms a T-shape and which depends from hangers from a ceiling joist. No brayers appear to be provided for the other two stones; it is possible that iron tentering bars were fitted. All the bridgetrees are wooden.

The quant extensions with the belt drums remain but the governors have gone apart from one that lies on the floor.

The wall is recessed on the northwest side to provide a mounting for the sifter.


According to Moon a fourth pair of stones, driven by steam, was formerly installed here. It is thought a horizontal shaft entered the mill from the granary building; there are cut-off beams which may have supported the gears transferring the drive to the secondary upright shaft (see above).

 Preserved on this floor, though displaced, are the arms and spindle of the sifter along with the drive gears, a bevelled nut and a larger, solid bevel wheel, both all-wood.Notes were not taken of the ground floor layout.

(1) Nigel Moon, Windmills Of Leicestershire And Rutland (Sycamore Press 1981)

(2) Ibid 

(3) Ibid

(4) Ibid 


Tower mill, standing today


The tower has six floors. It had four patent sails, two double- and two single-shuttered, which revolved clockwise, also an ogee cap and a lofty eight-bladed fan. The hand-turning gear of the fantail was operated from inside the cap. On the dust floor is an all-iron wallower with forty cogs. This drives the sack hoist by friction from its underside. The upright shaft is iron and made in segments. Below, a wheat cleaner remains which is belt-driven from the great spur wheel on the floor below this. The spur drives a wooden cogwheel which drives a four-foot diameter iron belt wheel on the cleaner floor which drives the cleaner by a belt.

 On the stone floor are the four pairs of stones. Three are overdriven and consist of two French and one Peak, the fourth is an underdriven French stone. The great spur wheel is all-iron, in one casting, and has 105 cogs. The three stone nuts are all wood. The spur also drives another wooden cogwheel which drives a secondary upright shaft to the two floors below.

 The main upright shaft terminates on the stone floor. The secondary shaft carries a belt wheel on the floor below which drives the underdriven pair of stones. Beneath the spur is a wooden pulley which once belt-drove a set of pulley wheels on the wall. These in turn belt-drove the reel flour separator on the next two floors. On the plaster of the wall is written “J Elson millwright Stamford August 1921”. The stone vats are of wood and circular in shape. The fourth pair of stones would seem to be a later addition, for they are out of alignment with the great spur wheel, which meant they had to be underdriven. They have a more modern bridge tree and governor system. Finally, there are traces of a hole being knocked in the wall of the stone floor, possibly to get this set of stones in. One stone has “T Child Leeds” inscribed on it.

 The governors, one for each set of stones, are situated on the roller floor. The bridges for the three sets of overdriven stones are of wood and of the conventional type. The secondary shaft, as well as belt-driving the underdriven set of millstones, also belt-drives a small roller mill, made in Zurich to Wegmann’s patent. This has two pairs of porcelain rollers. The adjustment for the space between the rollers is a spring and screw thread which came in in about 1879. This plus the fact that the rollers are smooth, a feature Wegmann dropped in 1878, seems to point to the machine dating from the late 1870s or early 1880s.

 The reel on this floor is belt-driven, as already mentioned from the spur wheel. The flour seems to have been fed direct from a French stone. The flour which reaches the end of the reel is brought back the way it has come by a belt-driven Archimedean screw. This feeds it into another reel for further sieving on the floor below. The roller is fed from a bin filled from the stone floor. An iron column takes the weight of the upright shaft on this floor.

 On the dresser floor is situated the reel mentioned above and a further bolter and wire machine. This second bolter is fed direct from the roller plant. The bolter itself is belt-driven from the bottom of the secondary shaft, which drives an iron pinion which drives the dresser itself. It has a maker’s plate which says “Pinner, Maker, York”. There is also a loading door on this floor giving access onto the stage. On the ground floor the old weighing machine survives. There were originally two entrance doors, but one has been blocked up.

(Nigel Moon, Windmills Of Leicestershire And Rutland, Sycamore Press 1981)


Tower mill, standing today


The tower is built of ironstone. The windshaft is of iron and the clasp-arm brakewheel, the brake, the wallower and the upright shaft of wood. The sack hoist is a friction drive off the wallower. On the third floor is a crownwheel with 72 cogs. What it drove has been removed but it was most likely a grain cleaner, as the surviving chutes from it feed directly down to the millstones. On the second floor are the storage bins, which were filled from the third floor. On the first floor are the three sets of stones, one peak and two French. A line of holes in the floor probably indicate that a dressing machine was at one time situated there.

 The great spur wheel is of wood with iron segment teeth bolted on to its rim to drive the stone nuts, and on its underside are iron cogs which connected with an iron pinion wheel which was in turn driven by a belt wheel which connected to the engine. On the ground floor are the three governors, one for each set of stones, and the wood bridgetrees and tentering gear.(Nigel Moon, Windmills Of Leicestershire And Rutland, Sycamore Press 1981)