Posted on

Technical descriptions of English windmills


DEAN-WITH-SHELTON, Upper Dean, tower mill

Standing today

The tower mill at Upper Dean, Bedfordshire is an interesting specimen in several ways, and a remarkable survivor. It stands at TL 041682 on the left side of the road leading from Dean to Shelton, in what are now the grounds of a modern house. To the north there used to run a bridle path which was the main approach to the mill. The first evidence of a windmill here occurs in a Feet of Fines of 1609-10 which records an agreement with respect to a dispute between William Towse and Thomas Grist, plaintiffs, and Thomas Dacres who was thought to have denied them possession of property that was rightfully theirs. The property in question was the manors of Overdeane and Netherdeane, with a windmill in each. The Netherdeane mill was the ancestor of the one which stood there until 1959. On Jeffreys’ map of 1765 both mills are shown occupying the modern sites; the land on which the Upper Dean mill stood was then called “Mill Field”. The mill was in existence at the time of the 1835 Ordnance Survey on which it is named “Dean Mill”. Whether it was the same one as that recorded in the seventeenth century is uncertain but it was probably a small post mill, open trestle at a guess. The present tower mill was built to replace it for William Bliss in about 1850 (Dolman, 1983, says 1856-7 and that the post mill, which did not occupy the exact site of its successor, had been demolished c1830 but this appears to be wrong) and in 1931 a datestone commemorating this, let into the brickwork at the top of the tower, was still decipherable. The names of W Eaton (1857), J E Mehew and William Hall were at one time recorded on the milling floor (described as such by the Bedfordshire Historical Record Society, see below, and presumably the stone floor) and directories give J Peck in 1864, Thomas Eaton in 1869, Thomas Mehew in 1877 and Charles Hall, probably a relative of William who had succeeded him in the post, from 1885 until 1903. Charles Hall was working the mill at the time of its closure in 1906. The property had been purchased by J W Rawson Ackroyd from the then owner “and others interested in it” in 1875, and from him it passed to his daughter Mrs E L Wade of Dean Grange(1).

   After ceasing work the mill then decayed for nearly a century and at the end of that period, astonishingly, still retained one stock with fragments of two of the sails attached – as in fact it still does. Apart from one or two of the Norfolk drainage mills these must be the last unrestored sails on an English windmill, which renders the mill of particular importance. The stock’s survival is due to its being of oak instead of pine which was more usually the case. The original cap roof had gone by 1958 and the remains of the fantail and fanstage fell off shortly afterwards. Part of the winding gear survived until recently but all of it has now gone, unless it has been placed inside the mill. The other two sails had gone by 1931(2) and may have been removed while the mill was still in use. The spider and triangles remain today.

   The process of decay seems to have been a gradual one, and at the same time the mill’s isolated rural location, in the heart of the countryside near the Cambridgeshire/Bedfordshire border and some distance from the nearest main road, served to protect it from the developers. In the early 2000s the latter finally caught up with it but to their credit – and this is rather rare nowadays – the County Council insisted that instead of being absorbed into the new house which was built on the site, the mill should be kept separate and also conserved with a new cap, built I understand by Vincent Pargeter, to keep out the weather and protect the surviving machinery from further deterioration. It is surprising, though also pleasing, that the original derelict sails have been retained; presumably there is some means of preventing the windshaft from falling down inside the mill, as the timbers of the cap frame must be much decayed after many years’ exposure to the weather. New doors and windows have been made and cracks in the brickwork repaired. A full restoration is still awaited but if one is ever carried out the mill’s small size would be an advantage here.

   Where surveying and recording are concerned, the mill seems to have been largely ignored by Rex Wailes and the entry on it in the Simmons Collection is in many ways sparse, for one thing lacking the technical descriptions drawn up of many mills during that period by Wailes, Denis Sanders, Stanley Freese, Ronald Hawksley and Simmons himself. Unfortunately in recent years the interior has more or less collapsed, which among other things makes interpretation of what remains more difficult.

   Regrettably no photograph of the mill in working order has yet been uncovered but from images of the derelict structure in the 1930s it is easy to picture what it must have looked like (Peter Dolman did quite a good drawing to that effect which is in his notes at the Mills Archive). The small three-storey red brick tower has a fairly steep batter; it is 46 feet in height and 18 feet across the base, with 18 inch thick walling(3). There is a large loading door on the second floor on the southern side, but no stage was necessary due to the building’s small size. There were four single-sided anti-clockwise patent sails with leading boards. They came fairly close to the ground necessitating two entry doors, on the western and north-eastern sides.

   The pepperpot-shaped dome cap, with its short finial, was vertically clad with broad weatherboards and had a scalloped petticoat like that of Cranfield mill (demolished in 1966) which was separate and not an extension to the cap boarding. At the rear a small pent-roofed extension gave access onto the fanstage, the upright timbers of which were inclined and braced to the cap roof near their lowermost extremities, not in my view the best arrangement if structural rigidity is desired although there could have been further timbers higher up which disappeared before the photograph was taken. On the spindle of the eight-bladed fan, and near its end was a nut meshing with another on a long vertical shaft which was steadied by a bracket projecting at a slight angle from one of the upright members of the fanstage. Near the bottom end of the shaft a third nut meshed with the teeth of a vertically mounted gearwheel on a horizontal shaft (still extant c2000) which presumably took the drive to the cogs of the rack(4). Full details of the construction of the cap frame and curb are difficult to make out from ground level and I will not attempt to do so other than to say that there appear to be at least five truck wheels, of iron with five arms each. Four are mounted on the undersides of the main sheers at the points where the lateral timbers of the cap frame are fixed to them, the fifth on the rear lateral timber of the frame; if there is a sixth bolted to the breast beam it is not visible from the ground.

   The following account of the internal machinery is based on visits by myself and/or my brother, Mr Mark Blythman, in 1988,  1995 and 2015, and photographs taken on those occasions and by K G Farries on 8th September 1956. When the later photos were taken partial collapse of the interior had already occurred.

   The mill being a relatively late one, most of the machinery was of iron. One exception was the wooden clasp-arm brakewheel, 7 feet 6 inches in diameter(5), which by the twenty-first century had mostly collapsed. The wallower was of iron with a wood friction ring from which the sack hoist was driven; most of this has now rotted away but the hoist itself remains. Its spindle turns in a horizontal wooden batten fixed to the wall of the tower, from whose ends longitudinal timbers go to the opposite side of the mill to give the whole arrangement rigidity. The windshaft, upright shaft, stone nuts and quants are iron.

   The upper floors were probably relatively empty, although it is difficult to tell because of the internal collapse, long before which the grain bins had been removed along with all the ladders in the mill(6). The upright shaft is very slender; the mill being underdriven, it is fairly long and in three sections with two dog clutches. The lowest section, carrying the great spur wheel, is the shortest; it has now broken away from the rest of the shaft and fallen to the bottom of the mill, revealing the clutch to be four-jaw. As might be expected only two pairs of stones, one French and one peak(7), on the second floor were fitted, plus a wire machine on the ground floor suspended from one of the ceiling beams. The stones were underdriven, in order to reduce clutter in what was to be a very small mill.

   The mill being so diminutive, this would have affected in proportion the size of all the gearwheels; the eight-armed iron mortice great spur wheel must have been among the smallest ever seen in this country. The quants are footed in a timber suspended by short hangers from one of the main beams in the stone floor above; one of them appears to have passed up through this or a separate timber just below it which is cut away to allow the stone nut to turn. The tentering screws remain but the governors and steelyards have gone. The stone nuts were lifted in and out of gear by jack rings.

   The size of the mill dictated economy in the arrangement of the working parts, and instead of taking the form of a separate set of gears driven from the great spur wheel or a crown wheel the drive to the wire machine is from a four-armed iron mortice bevel gear mounted on one of the stone spindles below the stone nut. This engaged with an all-iron bevel nut on a horizontal shaft which went across the mill to terminate in an iron mortice gear meshing with the nut on the wire machine spindle. The reel of the wire machine and part of its casing remain intact, but badly rotted. No engine drive appears to have been fitted at any point.

   There is a small, metal-lined circular opening in the wall of the tower on the northwest side, whose purpose remains unexplained although James Waterfield suggests it may have been for an exhaust pipe from a now bygone smutter.

    In Upper Dean what we have is a small, relatively late-built local mill which owes its existence to custom. It did not need to be very large because it was serving a small, isolated rural community (which still is that) where, also, traditional ways would have died hard, as seen not only in the fact that a windmill was built at all but in the lack of any evidence for a steam drive. It would however have been easier to build a windmill on a site where one had previously stood for hundreds of years. It was thought one might as well carry on the tradition; if the site had been completely new perhaps a small steam mill, of the sort beginning to appear in rural areas at this time and which did for many local windmills, would have been built instead.

Upper Dean is one of only three windmills in Bedfordshire to survive with machinery intact and thus have potential for restoration. It is engaging in its small size and somehow unobtrusiveness, and a personal favourite of mine. It’s good that it is in there with a chance, for it deserves to be, not least for having survived the vicissitudes of the twentieth century while so many others were demolished or house-converted; it might almost be called the one that got away.

Technical description based largely on survey carried out by G Blythman 10th October 2015. My thanks to the owner of the mill for arranging access.


(1) “The Windmills of Bedfordshire, Past and Present”, Bedfordshire Historical Record Society (hereafter BHRS) Vol 14   1931                 

(2) Muggeridge and Gregory photos, see below

(3) BHRS 1931

(4) Photograph in the Frank Gregory Collection, Mills Archive Trust, dated 1931; photographs by H E S Simmons (25th June    1932), Donald W Muggeridge (August 1933), Kenneth G Farries     (26th August 1958)           

(5) BHRS 1931

(6) Donald Muggeridge, 1932, in Simmons Collection, Science   Museum Library

(7) Peter Dolman, “Bedfordshire Windmills”, in “Wind and Water Mills”, journal of the Midland Wind- and Watermills Group, no.4 1983