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Technical descriptions of English windmills



All extracts from The Windmills Of Thomas Hennell by Alan Stoyel (Landmark Publishing, n.d.) are quoted by permission of the author.


Tower mill, gone SJ317845

A tall mill with a stage, Bebington mill had the hand-winded boat-shaped cap typical of the region, and ended its active life with four spring sails. The machinery was wooden apart from the iron wallower and the iron cog ring on the brakewheel though Hawksley implies the stone nuts were iron mortice. Four(1) pairs of stones were overdriven on the third floor and the sack hoist was off the great spur wheel. Hawksley notes “one pair {of stones} driven through countershaft gear”. There were an additional two pairs of stones on the first floor worked by steam.(2) Latterly the sails were missing, the cross having been sawn off, along with the cap roof.(3) The mill was demolished in 1968.

(1) Stoyel, TWOTH

(2) HRH in HESS September 1938

(3) Photographs in Mills Archive


Tower mill, standing today SJ287894

The Wirral peninsula was once renowned for its windmills. Bidston mill, built in 1794, is the most intact and best-preserved example, not only in that region but in the entire historic county of Cheshire. In fact it is one of the two most complete in the whole of the north-west, the other being Thornton in Lancashire. As such it is an extremely important survivor. Fortunately it is well maintained by a local preservation society. Due to its importance as a landmark among other things it has been restored on several occasions during the past 120 years, the first being in 1894 (it was one of the earliest examples of windmill preservation in the country). The elevated site, although attractively wooded, is perhaps a little too good for wind and the latter has played havoc with the external woodwork on occasions.

 The mill is a small one, and typical of the “primitive” type of north-west windmill, with common sails and hand winding, which bears marked similarities to those in North Wales and especially Anglesey. The cap is characteristic of the region, boat-shaped like those in Norfolk but with a straight ridge and gables triangular in section. A deep skirt of vertical boards protects the curb from water ingress, and the breast beam and the front ends of the sheers are exposed. Continuations of the sheers beyond the cap support a horizontal timber (currently stayed with metal rods to the tower, which means that the cap is effectively fixed) between which and the rear transverse member of the cap frame  is mounted the twelve-spoked wooden winding wheel whose rim is grooved to receive the luffing chain or rope. Though it was not possible to inspect the mechanism at close quarters, it seems that it operated on the rack indirectly. A pinion on the end of the winding wheel axle, not visible from below, engages an 8-spoked iron gearwheel on a short spindle mounted between the tailbeam and the rear transverse member. A nut on the spindle then meshes with the teeth of the rack, which is on top of the tower. The sails are hung on an iron cross.

 The brick tower is rendered with four iron crosses, forming the corners of a square, on its exterior in which tie rods within the mill terminate. Large stone blocks frame the sole entrance door, one forming its lintel. The windows are few and very small, being little more than hatches, and on the upper floors only, so unless some have been blocked up during past restorations this must have been a very dark and gloomy mill to work in. 

 Access to the dust floor is prohibited, but it is possible to glean some details by looking up from the bin floor. The final three courses of brickwork are stepped forward slightly with square openings, infilled with a wooden blocks, at intervals. The curb appears to be of the dead type. I could not make out the position, number or type of the truck wheels but the cap is steadied by a special framework suspended beneath it in the usual northwest fashion and constructed to allow the upright shaft to pass through it, unless this is simply part of the structure of the dust floor. Massive reconstruction at this level following gale damage does, however, make it hard to determine what was historically a part of the mill and what dates from repairs after it ceased work. The slender iron windshaft carries a split pulley of small diameter in place of the missing brakewheel. The latter, probably a solidly constructed wooden clasp-arm like the other large gearwheels in the mill, meshed with a wallower of that design, still extant. This wallower has a segmented rim with a bevelled upper face. 

 The wood upright shaft is short (the mill being overdrift), square in section and very substantial. In fact what strikes one is the massive construction of the whole of the main machinery and timberwork at Bidston, even though this is a small mill; it is another typically north-western feature. It has ensured that there has been much less need for replacement of original material below curb level. 


There are windows on the northwest and southeast sides. The upright shaft thickens out, with chamfering of the corners, just below the centring frame for the cap, where it is reinforced by a square of four iron bars. Four pieces of wood are tenoned into it where it passes through the hole in the floor to form a circle so that it is flush with the opening.

 The main ceiling (dust floor) beams rest at their ends on stepped brick columns built out from the walls; it was not apparent whether these were an original feature. The beams run northeast-southwest. Shorter timbers fixed laterally between them form a square around the upright shaft. Two further lateral timbers run between the main beams and the walls on the north and east sides, at a right angle to the former. Fixed between the undersides of the lateral timbers on the south-eastern side, which are rebated to take it, close to the “southern” main ceiling beam, is a timber with an empty mortice in it. Various square notches are cut in the inner faces of the north-western lateral timbers.

 The sack hoist was on the southeast side. It is now missing but its supporting framework remains. Two vertical posts, which extend down to the stone floor, are fixed to the inner side faces of the south-eastern lateral ceiling beams. In them are hinged a pair of horizontal timbers, one above the other and connected by an iron strap. The upper timber supports the bearing for what would have been the sack hoist spindle. Presumably, pulling on a rope attached to the lower timber, though it is located rather awkwardly for this, would move the hoist in and out of gear with whatever drove it. However, it is not in a position where it could have been engaged, by friction or cogging, with the wallower and I could see no evidence, though I may be mistaken, for a former crown wheel. If as Gareth Hughes believes(1) the hoist was driven by the inner of the two pulleys on the auxiliary drive shaft on the stone floor, which is directly beneath where it was and protrudes slightly onto this floor, then it would be a matter of tensioning or slackening the belt rather than putting something in or out of mesh with something else, unless there was some intermediary mechanism.


The absence of windows here is surprising, given that this part of a windmill was usually well lit, and reinforces my suspicion that they must have been blocked up at some point though I could see no indication of this. The stairwell and ladder to the bin floor are on the east side. The main timbers of the dummy floor supporting the upright shaft run northeast-southwest. Their ends rest on stepped brick buttresses as with the dust (and bin) floor beams; here the latter do not extend the full height of the floor. The footstep bearing of the upright shaft rests on a wooden bridge beam which is curved on its underside. Iron reinforcing brackets have at some point been fitted where this is tenoned into the rebated longitudinal timbers.

 The great spur wheel is another solid wooden affair, with deep clasp arms shaped to fit around the rim at top and bottom. An iron cog ring is bolted to the side face of the rim. Two pairs of stones, on the northeast and southeast sides, are overdriven via large iron mortice stone nuts, each with four short arms, on long square quants whose upper ends turn in lateral timbers between the main ceiling beams, which are directly above and run parallel to those of the dummy floor. 

 On each side of the dummy floor a lateral timber is fixed between the longitudinal timber and the wall, on a line with the bridge beam. On the south-east side the great spur wheel meshes with an all-iron bevel nut on a square iron layshaft, running above and parallel to the lateral timber, which at the other end carries a solid wood double pulley, one section of which is of smaller diameter than the other.

 Both stones are without their furniture. The north-east one rests on a raised wooden plinth which has rotted away in places. Lying displaced on the floor are a solid wood flanged pulley, with a rim consisting of seven segments with angled inner faces, and an iron shaft with a solid wood belt drum at one end. I suspect these items are part of the sack hoist mechanism (see above).


The entrance door is on the southeast side. There may have been another on the opposite side which is now filled in; it seems odd there should be only one given the danger to an unwary miller of being hit by the turning sails. The main ceiling beams run northeast-southwest. At the northeast end a cross-braced frame, probably of recent construction, helps support them. The bridge trees, which are curved, and brayers are mounted on hangers suspended from their lower or side faces. The governors are mounted on the stone spindles, in such a fashion as to seem almost integral with them. Like everything else in the mill they are robustly constructed. They have doubled arms, each pair being connected by lateral bars, and there are no links as such, the balls sliding along a rod which passes through them and through a thickened, drum-shaped section of the spindle, and presumably lifting the steelyard in the process though it is not clear by what mechanism. Short curved steelyards run to links on the ceiling timbers, but the second stages of each, which operated on the brayers to depress the bridgetrees, are missing. Both bridge trees and brayers are wooden.

 Against the wall on the northwest side, suspended from the ceiling, is a large and rather impressive groat machine, whose wooden casing, open at the bottom, resembles in appearance the winnowing cupboards once found on farms and often displayed in agricultural museums. The machine was driven from the outer of the pulleys on the auxiliary drive shaft on the stone floor(2). A belt passed down from there to a solid wood drum above and in front of the entrance door, on a very long octagonal wooden layshaft for which a hanger from a lateral timber in the ceiling acts as a steady bearing. On the opposite side of the floor the layshaft carries first a flanged wood pulley, partly rotted away, whose purpose is unclear and then a large eight-spoked all-iron gear engaging with a similar but smaller, and six-armed, gear in the same plane. This is mounted on a spindle which passes through the casing of the machine, within which a bevel nut meshes with another on an inclined shaft carrying a reel like that of a wire machine. Within a cowling is a four-bladed iron fan for blowing away dust. Separately driven, it is on a short square iron layshaft which ends outside the machine in a small solid wooden pulley which would have received a belt though from where is uncertain. Just in front of the machine the end of the main drive layshaft is located in a horizontal timber between two hangers. The other end turns in an angled timber, acting as a lever for putting it in/out of gear, which is pivoted in two vertical posts fixed to the inner faces of the main ceiling beams and terminating in the lintel of the door. 

On the northwest side to the left of the groat machine a curved timber, which serves no apparent purpose, runs from a ceiling joist to the wall.

(For all floors orientations are approximate)

Survey based on visit by G Blythman on 4th September 2010

(1) Windmill Hoppers 15/9/2012

(2) G Hughes, as above

GREAT SAUGHALL (aka Capenhurst mill)

Tower mill


A broad tower mill with a rather low, flat cap.  At one point it had a pair of spring sails and a fantail, which was unusual for Cheshire. It ceased working by wind by 1910 but retained windshaft, brakewheel, three sails and most of the machinery until the early 1970s when it was unfortunately converted to a house. At least the exterior has been quite nicely restored with replica sails and cap, although the latter is not the same shape as the original.

 A sketch by Thomas Hennell shows a governor of the usual northwestern type, mounted on the stone spindle extension (the stones being overdriven)(1) . There was a wire machine(2).  

(1) Stoyel, TWOTH

(2) R J de Little, The Windmills Of England, Colewood Press 1997


Bevan’s Mill

Tower mill, standing today


Threapwood mill is a short, squat tower mill with a parallel-sided section at the top incorporating the dust floor. Last thought to have worked c1880, it has been derelict for well over a century and is now in a ruinous condition and becoming overgrown both inside and outside. An area of brickwork is very badly damaged and has several large cracks running from it. The cap roof, which was typical of the region, and the large and impressive chain winding wheel were removed in 1933(1). The windshaft is of wood with an iron poll end and the brakewheel of clasp-arm type. Both were still in position in 1974 when the mill was seen on an SPAB visit, but by 1986 when G Blythman visited the windshaft had fallen to the bottom of the mill smashing the brakewheel in half. The floors and machinery had collapsed into a heap from which it was possible to pick out various items such as the upright shaft, which is square and wooden, the wallower (wood also), stones and tentering gear supports. There were three pairs of overdriven stones, one of which had gone when Alan Stoyel visited the derelict mill some time before the internal collapse(2).

 A drawing by Thomas Hennell shows that the great spur wheel was a substantially-constructed wooden clasp-arm. To its right are a pinion and layshaft carrying two wooden pulleys one of which was probably for the sack hoist and the other the machine drive. Stoyel believes the great spur wheel could not have meshed with the pinion as the latter is a face gear, so the nature of the power take-off is unclear.(3) 

(1) SF 1941, in HESS

(2) Stoyel, TWOTH

(3) Ibid


Tower mill, standing today


This is a large and potentially impressive six-storey red brick tower mill which retains its boat cap, windshaft, brakewheel and winding gear and is maintained in good condition. It is typical of the region. Unfortunately all the machinery below the curb is missing, the interior having been converted to living accommodation. Winding was by endless chain; a pinion on the spindle of the wheel meshed with a larger gearwheel on a horizontal shaft carrying a further pinion engaging the rack.(1)

(1) Stoyel, TWOTH