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Technical descriptions of English windmills

WARWICKSHIRE A-N

WARWICKSHIRE

BERKSWELL, Balsall Common

Tower mill, standing today

SP249759

Built in 1826, Balsall Common mill incorporates materials from a post mill, perhaps that which it was intended to replace and which may or may not have remained in use for a time after its successor was completed. The oak stocks and crosstrees were used as floorbeams and the head and tail wheels as the brake- and great spur wheels respectively.(1)

 This is probably the most typical surviving West Midlands tower mill, in anything approaching a complete state at any rate. It was last worked by wind in 1926 and by engine in 1948; the cap remained on and the internal machinery intact, making possible eventual restoration which began in 1973. Repairs were carried out recently and the present owners are maintaining the mill in good condition. It is one of six in the county of Warwickshire which remain mechanically complete within.

 The small red brick tower, whitewashed inside, contains three floors plus the very low dust floor. It has a boat-shaped cap characteristic of the region, which is tarred with a petticoat of vertical boarding and is winded by hand.

 The cap frame, which appears to be the original, consists of the breast beam, sheers, bowed sprattle beam, tailbeam and a final lateral timber above which the spindle of the winding gear passes. The whole turns on an iron curb with an iron rack. The former is live; there are five rollers, one under the breast beam, one each at the forward ends of sheers and one each on the sheers where the tailbeam is mated with them. Six truck wheels are provided: one each at the forward ends of the sheers near the rollers and one on each sheer where the sprattle and tailbeam meet it. They are mounted in wooden shoes bolted to the sides and undersides of the timbers.

 The mounting for the large 12-spoked wooden winding wheel is within the cap, below which the lower half of its circumference protrudes. It was turned by pulling on a chain aound its grooved rim. Its square iron spindle, whose other end is located in a  box on the tailbeam, carries a nut meshing with a six-spoked iron toothed gear which transfers the drive to the rack.

 The mill ended its active life with two common and two spring sails which have been restored with a full complement of shutters in the springs, although it does not at present work. These are mounted on a wooden windshaft the section of which varies, being cylindrical (and thickened at the neck), squared for the brakewheel, then octagonal, then square again, and finally cylindrical at the tail. The large clasp-arm wood (iron bound) brakewheel, secured on the shaft by wedges and packing, is delightfully old. The rim is deep and in two sections, with an iron cog ring bolted on. The brake and brake lever are wooden. The vertical post in which the lever is pivoted is located at the forward end of the left sheer above the truck wheel.

DUST FLOOR

The iron wallower with its webbed central boss and eight arms has a wood friction rim for the sack hoist bollard, on which it operates via a cone clutch. The hoist is moved in and out of gear by a lever, worked by rope from below, which raises or lowers the horizontal member of its support frame in which its bearing is located. The upright shaft is octagonal and wooden.

BIN FLOOR

The walls here are lined with vertical boards. The northern half of the floor is taken up by a bin divided into two compartments. There is another bin on the south side between the two main ceiling beams, which run north-south; its framework is made up of four posts depending from the ceiling beams and boarded over. The sack trap is on the east side and the stairwell on the south-east.

Windows are provided on the east and west sides. There is a segmented wooden ring around the opening in the floor which the upright shaft passes through.

STONE FLOOR

The main floor beams here, which run east-west, are the whips from the old post mill. There are windows on the north and south sides and the stairwell and ladder to the bin floor are on the southeast. Two pairs of underdriven stones are located to the north and south. The northern pair is complete with its original all-wooden furniture. The casing and furniture for the southern pair have been dismantled and lie in a pile on the west side of the floor, where there is a modern turnip chopper fed by chute from the bin floor and driven from the spout floor, with an opening provided for the belt.

GROUND/SPOUT FLOOR

Like many spout floors this is a veritable conglomeration of assorted machinery, which is sometimes difficult to interpret.

 There are windows on the northwest and southwest sides and opposite doors on the west and east. The ladder to the stone floor is on the southeast; on this side in the wall there is a square aperture suggesting a filled-in window. On the southwest side is a meal ark fed by a chute from the stones. The timbers carrying the bridge beam of the upright shaft run east-west, with an iron reinforcing strap going diagonally from the bridge beam to the southern timber. The clasp-arm wood great spur wheel is fitted with an iron cog ring and beneath it is a wood disc which received the governor drive belt. The stone nuts are large and of solid wood, iron-bound. Vertical rods with hand grips are provided for manually taking them in/out of gear.

 The tapered stone spindles are mounted on wooden bridge trees running parallel to the dummy floor beams and carried on hangers from the ceiling. There appears to be one governor for both pairs of stones, mounted on a block of wood on the northern side face of the southern main dummy floor beam. The steelyards go south-west to a link, with a hand tentering screw, on the western end of the southern bridge tree, and north to the eastern end of the northern bridge tree via two links. Each of the wind stone spindles is fitted with an extension in the form of an iron rod passing through the bridge tree to end in a hand screw.

 On the east side the great spur wheel meshes with a third nut, of the same type as the others, on an iron secondary upright shaft encased in wooden trunking, with below the nut a solid wood pulley of slightly larger diameter. This is the final stage of the engine drive, which entered the mill in the form of an underground shaft. The vertical shaft is steadied by a bearing bolted to the side face of the northern main timber of the upright shaft support frame. A belt went from the lower pulley to one of two small pulleys on a north-south layshaft which is flanked by the two longitudinal timbers between the main dummy floor beams on the west; from the other, southern pulley a further belt passed up to the stone floor where it drove the turnip chopper.

 The eastern of the two longitudinal timbers serves no apparent purpose but the other supports the spindle of a very large solid all-wood iron-bound upturned face gear which drove the wire machine as at Norton Lindsey mill. Here the mechanism appears to be incomplete. The cogs of the face gear mesh with an iron-bound all-wood solid bevelled cogged nut on a square iron layshaft going north-east to a bearing on the northern bridge tree. Below the face gear on its spindle is a large wooden flanged disc which obviously received a belt though it is not clear from where. At Norton Lindsey the drive was from a crown wheel on the floor above, but no such arrangement is present at Berkswell. The wire machine itself is on the north-west side. Part of its reel appears to be missing.

 Between the two longitudinal timbers is a lateral timber in which is located the bearing of the short spindle of a pulley whose purpose is unclear, although to the south and left of it is a kibbler with a wooden hopper and iron-toothed gearing, probably dating from the late nineteenth or early twentieth century. However it appears to be be friction driven from the rim of the face gear of the machine on the right hand side.

 On the southern main dummy floor beam, beneath and towards the right side of the great spur wheel but not in a position where anything on it could have been driven by the cogs of the latter, is a vertical iron spindle carrying a solid wood flanged belt drum, below which is a plain solid wood disc. The belt, which is still present but not engaged, appears to have gone from the wood disc at the foot of the upright shaft although this would have left no room for the governor drive. The upper bearing of the spindle is located in a stub timber between the dummy floor beam and a hanger. 

The two halves of the reel of a very large wire machine, not that installed here (there would have been no room for it) may be seen leaning against the wall.

Based on survey carried out by G Blythman 3rd August 2013

(1) Adam Marriott, Windmill Hoppers website August 2013

CHESTERTON

Tower mill, standing today

SP349593

From Arthur Titley and H D Haines, “A Warwickshire Windmill and Some Notes on Early Millwrighting”, 1953:

 “The windmill which is the subject of these notes is that at Chesterton, about five miles to the southeast of Leamington, in the direction of Banbury and the Edge Hills. It is interesting because the date of its original construction is known, and although it is not now in working order much of its machinery is still in place and in an excellent state of preservation, and possesses many features of undoubted antiquity. The mill is on the estate of Lord Willoughby de Broke, and bears upon the small gable of the rotating head the date 1632 and the initials EP, those of Sir Edward Peto or his son Edward, members of the family to whom the estate then belonged. At a short distance away is still to be seen the walled garden that belonged to the mansion, which has now disappeared, but was then the chief seat of the Peto family. The mill stands upon high ground, from which a fine view is to be had of the surrounding country. Close by passes the old Roman Fosse Way.

 The building of Chesterton windmill is supposed to have been originally an observatory built for Sir Edward Peto and, together with the Manor House of Chesterton (now pulled down), designed by Inigo Jones, although there is no documentary evidence to this effect. At least it is in his style and of his period and was evidently the work of a man of ability. At the date of its erection scientific interests had begun to engage the attention of men of wealth and leisure. The windshaft gable of the revolving ring shows some evidence of being an addition when the shaft was put in; otherwise the revolving ring appears to have been an original part of the building.

 The lower storey of the mill is pierced with six arched openings. The outer and inner faces of the arched openings are areas of circles struck from the common centre of the building; their sides are radial from the same point. The bases and imposts of the piers and the arches are moulded. A moulded string-course runs round the tower below the windows and a cornice caps the walls. The windows have external mouldings and moulded mullions and transoms. On the first floor are placed the two pairs of stones, and above the second floor are the windshaft and principal gearing. There seems originally to have been no room provided for the sacking and weighing of the meal, but a two-storied wooden erection of much later date, below the level of the first floor, served this purpose during the latter useful days of the mill. It seems probable that originally the meal was sacked upon the same floor as that upon which the stones were placed, and that the sacks were lowered into carts backed under the arches below. There is no evidence that any form of flour dressing machinery was ever used.

 The floors are reached by open oak stairs, and under the confined space below the flight by which the upper floor is reached is situated the governor, or “lift-tenter”, for varying the load upon the mill by raising or lowering the top stones as the wind fluctuates in strength. Upon the top of the circular wall of the tower is the stationary curb upon which the head of the mill rotated as it was turned to face the direction of the wind. This curb has been reconstructed at some time and is faced with a cast-iron roller-path of inverted channel section, attached to the oak curb below it by means of wood screws. Carried by 15 cast-iron rollers running upon the roller path is the corresponding oak curb upon which is built the heavy framing which carries the windshaft, and the framework of the lead-covered roof. Nine rollers bearing upon the vertical faces of the roller-path kept the head to its track, and it can be seen that it was the decay of the oak upon which the channel is fixed that, by allowing the track to spread, caused the final stopping of the mill.  The head of the mill was rotated by hand by means of a winch with worm and spur gear and a pinion which engaged with the beech cogs of a circular rack lying on the wall within the roller-path. The spindle of a wind-vane upon the apex of the roof was continued to the interior of the mill, and by an indicator enabled the miller to see the direction of the wind.

 The windshaft is of oak, having cast-iron gudgeons. The one forming the main bearing is what is known as a “cross-tailed gudgeon”; that part of it which forms the attachment to the oak body of the shaft is cast in the shape of a cross. A cross-shaped mortice was cut right through the shaft to fit this; iron rings bolted together in halves were placed upon the body to prevent its expanding; and wrought iron wedges were driven in between the cast-iron and the wood. The main journal is next to the cross, and outside this the poll end is formed with two box-like openings at right-angles to each other, to take the timber stocks to which the common sails were fixed.

 In “Graphic Illustrations of Warwickshire” by Alex. Blair, 1829, is a woodcut showing the stocks passing through mortices in a timber windshaft, so that the present poll end must have been an addition of later date.

 The carriage upon which the main journal is supported is of cast-iron let into and bolted to the oak head-stock which is in turn borne upon the framing of the head. This carriage is fitted with a semicircular bottom brass prevented from turning by means of two projections cast upon it fitted into corresponding recesses in the body of the carriage.

 The gudgeon at the tail end of the shaft, which takes the thrust due to the pressure of the wind, appears to be of wrought-iron about two and a half inches square with the end turned to form the journal and a collar to take the thrust. A mortice is cut from one side of the oak body of the shaft to take the square shank of the gudgeon, and the superfluous space is filled up by an oak filling piece and a bolt passes through the lot. Iron rings driven upon the circular end of the body and iron wedges driven in at the side of the gudgeon complete the fixing. This end of the shaft is carried by a bottom half brass let into the cross-beam of the head framing with a wrought-iron forged cap held by bolts and coach screws to the beam. The thrust is simply taken upon a square piece of brass backed up by an iron plate and wedges. The brakewheel is particularly interesting as showing what is probably the method of construction used for many centuries. Its rim is built up of four segments of elm morticed and tenoned together, their straight inner edges forming a square when in position. Four annular segments breaking joint with these are attached to one of their faces by means of iron bolts and 120 oak pegs or tree-nails, in a similar way to that in which the planking of wood ships is fixed to the framing. Through the double thickness thus formed mortices are cut for the sixty beech cogs which drove the trundle or wallower upon the vertical shaft. Round the periphery of the rim of the wheel thus formed are bolted oak laggings with the grain running circumferentially, to form the rubbing surface for the iron brake strap which completely surrounds the wheel, and by means of which the mill was stopped.

 The rim of the wheel is carried by four “compass” arms which consist of two timbers halved together at their crossing and let into and bolted to the first mentioned rim segments having straight sides. In order to enable these to be put together, the square of the shaft has two mortices cut through it at right angles. The length of these mortices is a little more than one and a half times the thickness of the arms in the direction of the axis of the shaft. This enables the second pair of arms to be put through the shaft when the first pair are home. The second pair being them driven into position upon the first, folding wedges of oak were driven into the vacant spaces of the mortices and all made tight. Small wedges were also fitted upon the opposite side of the arm to adjust the face of the wheel so that it ran truly.

 The shaft is strengthened near the arms by an ingenious arrangement which enables it to be cramped up equally on each side of the square. Four square screwed bolts with eyes forged at one end are placed with the screwed end of one inserted through the eye of the next, so that when the four eyes are tightened the size of the enclosed square is equally reduced.

 It is interesting to notice that the lever actuating the brake is weighted at its end, so that when the lever was in its normal position the brake was on. It was taken off by pulling a rope which was attached to the end of the lever and passed over a pulley sheave, so that the arrangement embodied the underlying principle of modern safety devices, that the normal position was the safe one. This arrangement is shown in an illustration of a windmill in Ramelli’s book of 1588.

 The wallower or trundle is a lantern pinion, a common construction in old millwork. It consists of two wood discs made in halves and hoped with iron bands. The discs are held apart by four wood distance-pieces and bolts passing through them. The beech “rounds” forming the teeth are turned to two diameters where they lie in the thickness of the lower disc, and to fix them wedges are driven into saw-slits in their lower ends.

 The ends of the upright shaft where the wallower is fixed upon it is square. Below the trundle it is sixteen-sided and of a larger dimension. Four of the sixteen flats of the shaft are continued into the thickness of the lower disc of the wallower, the remaining flats being beveled off to meet the square. Four key-like projections are thus left, which form a secure driving attachment to the trundle, as well as ensuring its vertical position.

 The gudgeons of the upright shaft are similar to that forming the thrust bearing of the windshaft, but are formed without the end collar. The gudgeon at the upper end is carried in two-part brasses secured to the centre beam of the head framing by means of a staple iron. The legs of the staple pass through the beam and through an iron plate and are threaded at their ends to take the nuts which fix them. The gudgeon at the lower end is borne by a footstep brass the horizontal position of which is adjusted by four set-pins in the bridging box at the floor level.

 A wooden great spur mortice-wheel with compass arms made and fixed in a similar manner to the brakewheel drives cast-iron pinions or stone nuts upon the wrought iron spindles of the two upper stones. The spindles are carried by bridging boxes in the same way as the vertical shaft. These are fixed upon oak bridge-trees, one end of which lie in mortices cut in the vertical posts of the hurst frame that supports the stones and their gear. The free ends of the bridgetrees are supported by other timbers known as “brayers” or brays, the fixed ends of which lie in similar mortices but are provided with a vertical screw adjustment. Their free ends are attached to long iron levers the ends of which lie in holes in lugs on the sliding collar of the governor, an arrangement we have not met with elsewhere. In Lincolnshire tower mills we have seen as many as four pairs of stones controlled by one “lift-tenter”, but in this case the levers from each pair of stones were connected together before reaching the governor, thus simplifying this detail. Quite commonly too, separate governors are provided for each pair of stones.

 A sack hoist was worked from a friction disc upon the vertical shaft, one end of the barrel shaft being carried in a wooden compound lever by which the necessary pressure was obtained.

 Each pair of sails is built up of three timbers. One of these, the stock, passes through the cored opening in the poll end so that it projects on each side. A shoulder is worked upon one arm forming a stop against the gudgeon. A wood cleat is nailed in the corresponding position on the other arm, and wood wedges driven in between the stock and the casting complete the fixing.

 Upon each of these projecting arms of the stock is fixed by means of three through bolts and two iron straps, the whip which is morticed out to take the cross-bars. Three longitudinal strips bolted to the crossbars complete the framing upon which the canvas was spread. At the inner end of the each frame an iron bar carried iron rings to which the inner edge of the sail was lashed. When the sail was furled these rings sliding upon the bar allowed the canvas to be rolled up upon the whip. The sails were of canvas, with a leading-in weatherboard of wood.

 The cross bars project upon the advancing edge of the whip and carry a permanent “weather-board” which is canted outward to a greater angle than the rest of the sail by means of wedge-shaped wood packings.

 The machinery of the mill appears to have been reconstructed in the year 1776 as that date is cut together with the initials IL upon the timber of the windshaft. By that date a good deal of cast iron work had been introduced into millwork, but it is not known when its use in engineering work began. We know that Smeaton first made windmill shafts and similar parts of cast-iron about 1755, and we also glean from his remarks that such details as the cross-tailed gudgeon we have described were familiar to millwrights in 1767 when he constructed his waterwheel and pumps at the London Bridge waterworks.

 It is possible that a careful examination of old mills and a search for evidence of the date of their building or reconstruction might throw light on the period of the first use of cast-iron and brass for the smaller parts of machinery. In Tudor and earlier times it was usual for the shaft to be entirely of wood except the gudgeon taking the thrust. In these old shafts, moreover, the stocks were fixed in mortices cut through the end of the shaft itself. The illustrations in Ramelli’s work, while showing many details of the timber shafts, gearing and framework of millwork in Tudor times, afford little or no evidence as to what material was employed for the actual bearings. Even today the upper ends of mill spindles in windmills in which the stones are driven from above often run in simple blocks of hardwood. It is hard to believe however that the main journal of a windshaft and the bearing upon which it turned were ever both entirely of wood, seeing the great weight that had to be carried. Leupold (1725) gives an illustration of one of these shafts in which the main journal is formed in the timber and iron strips were let longitudinally into the neck so that at least half the bearing area was metallic.”

An article on the mill by D Ogden and G M Fuller in Industrial Archaeology Vol.13 no.4, Winter 1978, contains a technical description.

HARBURY

Tower mill, standing today

SP372600

MWWG Journal no 10, 1990:

Harbury Windmill

Part 2 – The Survey, by Barry Job

The decision to survey Harbury Windmill was prompted by the submission of a planning application to convert part of the mill to residential use.  In its later years the ground floor of the mill had been used as an engineering workshop. In association with this use a number of unsightly buildings had been added around the mill base.  One of these apparently incorporated an old brick barn but this has been much altered and rendered over.  Otherwise, these outbuildings are of no merit and the planning application intended replacing them with a two-storey dwelling constructed of reclaimed bricks connecting with the two lower mill floors. The lower mill floors would also be incorporated in the dwelling but as these are empty of mill machinery the effect of the conversion on the mill might be regarded as minimal. The machinery on the higher floors is largely intact and it was thought that the conversion would restrict access. Consequently the MWWG were informed of the proposed conversion through Bill Seaby of the Warwickshire Museums Service, with a view to a group of Midland Wind- and Watermills Group members carrying out a survey of the mill.  Permission to gain access was kindly given by the new owner Mr P Mason and a number of members arrived at Harbury on the morning of 15 April 1989.

 In the last few years the original boat-shaped cap, which had been latterly clad in corrugated iron sheet, was removed and replaced with an apex-roofed structure pierced by windows to the front and rear. Whilst this had the merit of being weathertight and being similar in basic design to the original it lacked any of the curves of a boat-shaped cap.  Other alterations carried out at about the same time included the replacement of windows and doors and removing the remains of the stage timbers with the resulting holes in the tower being bricked up.

 Whilst appreciating the difficulties of carrying out a mill survey with a number of people, the restricted time available necessitated a team approach.  The intention of the survey was to record the details of the mill tower and all of the machinery within it, but not the outbuildings or the new cap.  Thus the members divided into small groups to measure and record their allotted part of the mill.  A centre line was projected onto every floor of the mill to allow offsets to be taken and to establish a uniform approach. An electronic surveying instrument was used to measure the vertical height to each floor.  This quickly showed that the height to the curb was some sixty feet.  Thus with the original cap in place the total height would be approaching seventy feet.  For the sake of uniformity of presentation it was decided that one person would supervise the scale drawings.  It is hoped that any errors which have crept in whilst transcribing the measurements are not too serious. 

Thanks must go to Bill Seaby for initiating this interesting exercise, to the Group Members and friends who were present on the day to give their support. 

Part 3 – Description, by Barry Job

Standing in Mill Lane, this large windmill dominates the small village of Harbury. The height of the tower, some 60 feet to the curb, necessitated the use of a stage at third floor level to reach the four common sails, each sail must have been over 30 feet in length.  The batter of the tower is continuous but it appears to have been constructed in two sections.  The first two floors are of stone and have an octagonal interior which contrasts with the circular interior of the four other brick floors. The tower is pierced by a number of windows and a number of doors; three on the ground floor, one on the first floor for loading wagons and two on the third floor to reach the stage.  In the window jamb on the first floor are the initials IBMD and RC and the date 1814 while set in the opposite wall is a weight stone presumably to convert from Gallons to Pounds and from Bushells to Stone and Pounds.

 The first 3 floors are devoid of machinery but presumably this was not always so.  Only on the third floor are the original sack hoist flaps to be seen but on the other floors their position is shown by various trap doors.  However on the first and second floors this lies to the south whereas it lies to the north on the other floors.

A pulley bolted to a ceiling beam on the second floor was probably fixed to accommodate this awkward change of position.

 The third floor contains one bolter, its bearings being suspended on timber framework from the ceiling.  The matching machine on the opposite side of the floor is missing.  The drive is taken from the spur wheel above. The timber drive shaft carried a clasp arm gear wheel with the wooden teeth set at an angle to the horizontal to drive the iron cog on the inclined bolter shaft. Also on this floor directly below the stones are the belt drives to the flyball governors which control the tentering gear.

 The fourth floor is the stone floor which carries a pair of French Burr stones of 49 inches in diameter and a pair of Derbyshire Peak stones of 52 inches in diameter.  These still retain the major items of stone furniture although their lack of wear suggests that they may be replacements.  No evidence of the grain feed arrangements is present. The stones were overdriven by wrought iron quant posts and stone nuts, these were located at the driven end in a glut box fixed to cross ties.  Meshing of the stone nut with the spur wheel was retained by a wedge in a rectangular groove in the box.  A safety chain was fitted to the glut box to limit movement of the quant during disengagement. At right angles to the stones is the wrought iron bolter drive shaft. The top of the shaft is bolted to a moveable timber arm slotted into two support beams.  The arm is extended to form a handle, the whole being locked during the operation of the bolter by a wedge. 

 The timber great spur wheel is of clasp arm construction and is keyed to the main shaft by timber wedges.  It is butt and lap jointed and is secured by 12 bolts.  The massive oak vertical shaft is bound at the lower end with two iron bands.  It is supported on a 3-inch diameter iron insert which rotated in an adjustable cast iron bridging box bolted to cross supports in the floor. Here the shaft is 16-sided but it becomes 8-sided and then square on the next floor.  Set in an awkward position close to the wall and under the bin floor steps is a winch for raising the stones for dressing. Timber supports carry an iron bound octagonal timber windlass drum. Two square holes have been let through the drum for the insertion of operating bars, which unfortunately are missing.  Hooks fitted in the ceiling beams above the stones would have carried pulley blocks.

 The fifth floor is the bin floor but all of the grain storage and feed equipment has been removed. All that remains to be seen is the vertical shaft, with a low rectangular curb around the hole in the floor where it passes through to prevent grain spillage falling to the floor below, and the sack hoist trap now fitted with a close fitting cover.  Access to the cap, which is some distance above, would have been by ladder but this is missing.

 Set in the ceiling are two main support beams which would have carried the cap floor joists but these are also missing.  In addition, they carry the wrought iron tie bolts which secure the curb ring.  Two other joists carry a support tie for the hoist mechanism.  This is of the conventional friction type; the drive being taken from an iron flange bolted beneath the wallower.  The six-spoked wallower is all of iron and engages with the wooden teeth of the brakewheel.  This is of heavy construction with a morticed and bolted frame.  The timber ring with the 74 teeth pinned through the back is supported by four timber segments on the front side and a continuous ring of iron flanges in two sections on the other.  The iron band brake is in sections and is operated by the weight of the heavy pivoted brake beam.  The brakewheel is wedged onto the windshaft and is also supported by tie rods.

 The massive oak windshaft, like the brakewheel, is showing the ravages of time and appears to be original. Shrunk and wedged iron bands strengthen the ends and help to secure the heavy iron poll end which is over 3 feet long and will accept sail stocks of 12 inches by 16 inches.  The other end of the windshaft is held in a tail bearing secured to the cap frame. The frame consists of morticed and bolted oak timbers of about 12 inches square. It is braced by tie rods and has four cap centring wheels bolted across the inner corners of the frame.  Each wheel is held in a cast iron box, the bottom of which can be unbolted to lower the wheel down from its axle.  Each wheel is braced by long tie rods to the adjacent wheels.  They run against the inside of the curb ring.  On the top of the brickwork the weight of the cap is taken by eight iron skids.  Only six skids are shown on the drawing for clarity, the alterations of the cap with the removal of original timbers and the substitution of a simpler cap structure has produced a situation which requires further work to decipher the original dimensions of the cap. Inside the brickwork the curb ring consists of cast iron segments, interestingly carrying various numbers of teeth to give a total of 159. Secured between the two rear beams of the cap frame is an iron pinion engaging with the curb ring to wind the cap and a rim gear on the same shaft. Unfortunately the pinion which drove the rim gear is missing although its angled support frame is still in place. There must have been further supporting framework extending to the rear to carry the pinion shaft and the large chain wheel to be seen in old photographs.

 Thus Harbury windmill is fortunate in having the majority of its machinery in position.  It is true that many detailed items are missing but the major interior components are present and it is tempting to consider that with the addition of sails and staging the mill could then be turning under windpower once again. 

NAPTON-ON-THE-HILL

Butt Hill, tower mill, standing today

SP458613

This mill is prominently situated on what may be an ancient site; a windmill is recorded here in 1543 and Adam de Napton and his wife Ellen settled two mills on themselves in 1348. The present structure is thought to date from the late eighteenth century.(1)

 The four-storey brick tower is built on a stone foundation, the bottom floor being entirely below ground level and entered by a cutting in the mound on which the mill stands as well as through an arched opening on its western side. The lower walls are 21 inches thick and the whole building is of very substantial construction.(2) The cap was domed with a short finial and latterly clad in sheet iron, which helped to preserve it intact for the best part of a century after work ceased here c1900. A pair of common sails likewise remained into the 1970s. Winding was by hand with the curb of wood and the rack on the inside. Some of the machinery survived when Simmons visited in the mid-twentieth century but unfortunately the mill was later gutted apart from the wooden windshaft and clasp-arm wood brakewheel, which are still present. The wallower, from which the sack hoist was presumably driven as Simmons does not mention a crownwheel and there was no provision for doing it off the great spur wheel, had gone by the time Simmons called. The square upright shaft and double clasp-arm great spur, the latter 5ft in diameter and located under the ceiling of the third floor up, were both of wood. There were three pairs of stones originally; two, a peak and a burr, remained along with one set of governors. They were overdriven via all-iron nuts on circular quants. A fourth nut on a vertical shaft descending to just above the sunken ground floor took the drive from an engine via a bevel nut meshing with another, 2ft in diameter, on a horizontal shaft passing through a tunnel from the engine house on the north side of the mill below the level of the mound.(3)

 In the mid-1970s the mill was externally restored with a rather hideous mock cap and sails, the former similar in shape to the original but containing a non-authentic window. A few years later the mill was converted to a house, with an extension built on, but at the same time its appearance was considerably improved by the fitting of a more authentic cap and common sails.

(1) R J Brown, Windmills Of England, Robert Hale 1976

(2) HESS

(3) Ibid

NORTON LINDSEY

Tower mill, standing today

SP224632

Notes on the structure and machinery of Norton Lindsey windmill, by W A Seaby, MWWG Journal 1982:

“The brick tower, built in alternate courses of headers and stretchers, is unusual in having very little batter.  It is therefore unlike those of Berkswell (Balsall Heath, Napton, Harbury and Thurlaston, or the somewhat more barrel profiles of Rowington Green and Packwood.  The tower windmill which formerly stood on Shrewley Common (demolished 1949) was also a structure with little inward slope towards the top, but its diameter was greater in relation to its height than at Norton Lindsey, which probably remains the most slender tower in brickwork surviving in the Western Midlands. 

The principal measurements are as follows:

                                                            ft  in        metres 

Vertical height including cap              42  6        12.96  Vertical height to top of brickwork           33  6          10.22

Height of cap and dust floor               18  0         5.49

Height of bin floor                              4    6        1.37

Height of stone floor                           8    0         2.44

Height of meal or ground floor          11   9         3.59

Interior diameter of curb                    12   9         3.89

Diameter at top of brickwork (outside)   14  9          4.50

Diameter at top of brickwork (inside)      2  9          3.89

Diameter of bin floor                         13  6          4.11

Diameter of stone floor                      14  6          4.42

Diameter of meal or ground floor       15  3         4.65

Exterior diameter at ground level       18  3         5.57

Length of wind shaft                           11  3         3.43

Length of main shaft                           25  0         7.63

 When the mill was to be sold by auction in 1804, together with the mill house, there were “five capital new stones, three of which are French”.  This suggests that despite the spare French burr the others were then as now the usual Peak stones.  Almost a century later this advertisement appears: “To let as a going concern.  An old-established Mill, wind and steam, in good order, bakery attached, 2 pairs of stones, 8-horse portable engine, small baking business, house, mill, stables, bakery etc. Rent £25.  Apply W F Blakeman, Norton Lindsey, Warwick.”

 In 1894 A H Summers, the Tanworth millwright, put on a new stock and sail, but from Blakeman’s letter quoted above one wonders if it was this mill or another which caused dissatisfaction.  The sails then measured 37 feet (11.28m), were cloth-covered and turned anticlockwise.  However in the last years of the mill’s existence it was the steam power rather than the wind which kept the mill in operation up to 1906.  A photograph exists which shows this windmill in the early 1890s, with all its four sails, having a different belt wheel – curved spokes instead of six straight spokes as on the existing wheel – and the steam engine shed sited to the south of the mill instead of the north where it was later known to have been.”  Between 1906 and about 1920 two opposite sails were dismantled, the other pair gradually disintegrating over the decades.  Now only two opposite stocks remain. 

 H E S Simmons made an inspection of the windmill on 3rd March 1944 but his description, based one suspects on too hurried an examination, caused him to make several errors in writing up his notes; so that the following account of the internal workings, taken both from Wilf Foreman’s elevations, plans and drawings, and personal inspection with John Bedington, Tom Mitchell and others, is corrected accordingly. 

 The hand-winding gear is operated by a 5ft 6in narrow-rimmed iron Y-wheel, with small gauge spokes placed closely together.  This turned through gearing a somewhat heavy 9-toothed iron nut directly on to the rack running round the top of the wooden curb (see drawing made from photograph taken in August 1976 before renewal of cap when this nut was removed). 

 The former cap, also of boat form but easily identified in photographs by a short post or finial protruding above its centre ribs, was steadied against the inside of this curb by trolley or truck wheels placed four a side in pairs.  The neck bearing is mounted on a deep and heavy round baulk held in position by massive iron brackets; the poll end is of the usual metal form.  The windshaft itself is of oak, octagonal in section, 1ft 6in diameter, except where the brakewheel is fitted, that part being 1ft 9in.  The brake wheel, with iron brake bands, is mostly of elmwood and of clasp-arm type, 7ft 8in diameter and having 71 fruitwood teeth. Engaging it is the 3ft 6in wallower also of elm, having 35 teeth, and on the underside of this, where the wheel is bevelled, a 1ft 9in solid wood drum is friction-driven for the sack hoist, the bollard with its former teeth sawn off, being extremely well worn.

 Throughout the mill the main timbers and gearing appear to be original and for the most part are in reasonable condition considering their age.  Immediately beneath the dust floor level the bins are enclosed in a low space and, where it passes through the bin floor, the upright post is boarded round.  This main shaft, 15 in across, is of Scots pine; it is octagonal except where wheels occur and the sections are then square.  Cut somewhat crudely on this timber, in the stone floor below, are the initials JS 18-3, the third figure of the date being dug out; possibly it was originally a diamond-shaped O, but looking now more like an elongated one.

 Two pairs of 4ft stones, Peak and French, both retaining their casings, are underdriven in the usual manner; but the grain chutes, horses, hoppers and damsels, etc., have gone.  Also on this floor, beneath the ceiling, a 6ft cross-arm wheel, set on the upright, and constructed of elm and pine wood was used with a belt and jockey pulley to operate an oak shaft some 10ft 9in long set near the wall on the west side.  At its lower end a spur wheel 3ft 3in diameter, with 56 wooden teeth engaging a 17-toothed iron pinion and spindle, worked an inclined dressing machine fitted close beneath the ceiling of the meal floor. {All this apparatus is still intact.}

 The 8ft, very heavy and almost solid elm great spur, having 100 “crab” teeth, is also set close below the ceiling of the ground floor.  Bolted on its underside is a 4ft bevel-toothed iron ring (face gear) having 112 teeth so that the same stones could be driven by either wind or steam power.  The latter operation was by means of a 28-toothed iron pinion and shafting to a 4ft diameter iron belt wheel set against the outside wall, the spindle having a backwards and forwards movement for disengagement.  The 27-toothed stone nuts are of wood, each 2ft diameter, with iron spindles, both being controlled by a lag governor, including steelyard, adjuster, chain and timber brayer.

 The doorways east and west are 6ft 9in high by 3ft 10in wide, each having a low arch with internal timber lintel.  The jambs and 2ft inner buttresses either side are carried out in rounded-off brickwork; but the former double doors have been replaced by single doors made from elm boards.  On the ground floor there are windows to the NNW and SSE, each 3ft 6in high by 2ft 6in wide; on the stone floor are a pair set N and S above the millstones; and windows E and W on the dust floor. All have low brick arches externally with rounded-off brickwork jambs internally.  Frames and glazing have been renewed in recent years and the woodwork painted white externally.

 The original wooden stairway, much repaired, remains at the lowest level; but there is now a ladder, set on the upper Peak stone, to reach the bin floor. A set of treads, two of which have broken away, leads to the dust floor; and there is a second ladder reaching some loose boarding laid across the sprattle beam and the main timbers at the top of the tower.  At ground level the flooring is paved with bricks; other floors have wide boards, somewhat holed and patched but supported on joists in the normal way.  The trap doors of the sack hoist are still in evidence on the east side of the mill.

 It only remains for me to thank Mr and Mrs Paul Waterworth who have given every facility for the carrying out of this combined survey.  Norton Lindsey is one of the few windmills of the western Midlands where the wood mechanism appears to be largely in its original state, although out of commission for more than 75 years.  It is to be hoped that the mill may long continue in sympathetic hands and that the interior repairs to ensure safety of machinery, floors and stairways may be carried out in the not too distant future.” 

(See original article for footnotes)