Cromer windmill, Hertfordshire
Cromer has Hertfordshire's sole-surviving post mill (though remains of other
types of windmill can still be found within the county).
More details can be found on the Cromer windmill page.
Hertfordshire Building Preservation Trust
The structure of the mill
The large wooden body of the mill is balanced on a huge main post
over 18ft high, around which it turns to allow the four shuttered sails
to face into the wind. The main post is supported by a collection of
timbers known as the trestle, protected from the weather by an
octagonal brick roundhouse. The trestle comprise two horizontal
crosstrees and four sloping quarter bars which together convey the
weight of the mill onto four brick piers.
The body or buck of the mill contains all the corn-grinding machinery.
It is reached by a ladder at the rear, above which is mounted the
eight-bladed fantail which is geared to automatically turn the buck so
that the sails face into the wind. The fantail turns two truck wheels
at the bottom of the ladder which run on a track encircling the mill.
A tour of the mill
Bin floor (top)
Here the iron windshaft carrying the sails on its outer end, enters the
mill. All the shutter in the sails are connected to the striking rod
which passes through the hollow windshaft. By pulling on a chain at the
rear of the windshaft, the miller can open or close the shutters
according to the strength of the wind, thus controlling the speed of the
sails. On the windshaft is mounted the wooden brake wheel, so called
because of the wooden brake band around its rim which acts to stop the
sails and windshaft turning. The sack hoist is driven off the front of
the brake wheel. This lifted sacks of grain from the roundhouse through
a series of trap doors to the top floor. Here the grain was tipped into
the large grain bins and was fed from these into the millstones below.
Stone floor (2nd)
On the stone floor the wooden cogs of the brake wheel mesh with the
teeth of the iron wallower which is mounted at the top of the upright
shaft. The two pairs of millstones are located on either side of the
upright shaft in the front or breast of the mill. Their driving gear
can be seen from the floor below.
Meal floor (1st)
The iron great spur wheel is mounted on the lower end of the upright
shaft. Its wooden cogs drive two iron stone nuts which each drive a
millstone on the floor above.
How the grain was ground
The millstones are fed from above by the grain bins on the bin floor.
Grain trickles into the eye in the centre of the millstones and
is ground between the upper revolving runner stone and the lower
stationary bed stone. A centrifugal governor is provided
to control the gap between the millstones and thus, the fineness of the
flour produced. The governor regulates the gap automatically according
to the speed of the sails. Manual adjustments are made with the
tentering screw by the miller. The ground meal is dischared down
the floor chute into a waiting sack on the meal floor. The sacks
of flour were then slid down the sack slide on the tail ladder into a
History of the mill
Cromer mill stands on an artificial mound where windmills have stood for
over six hundred years. The present mill was built shortly before 1720,
possibly as early as 1681. It was blown completely over around 1860 and
subsequently rebuilt. Milling by wind became uneconomic in the 1920s
and the mill fell into disrepair. It worked for a short time with no
fantail before finally ceasing work. One sail was blown off in 1929 and
the remaining sails were removed for safety. Apart from some repairs to
the body carried out in 1938, nothing more was done to the mill, and it
was left to deteriorate. An appeal by concerned local people in 1967
saved the life of Hertfordshire's sole-surviving post mill. On
completion of the first phase of restoration work the mill was presented
to the Hertfordshire Building Preservation Trust, the present owners.
The first regular open days were held in the summer of 1991 after
thorough repairs had been completed. The mill was brought into full
working order in 1998 after receiving grants from the Heritage Lottery
Fund and English Heritage. Money from visitors will help to maintain
the mill in its present condition for future generations to enjoy.
Facts and figures
- Height to rooftop - 38ft 6ins
- Dimensions of buck - 17ft x 13ft 4ins wide
- Main post - oak, 22in square 18ft 9ins high, 1.42 tons approx
- Quarter bars - oak, 11ft long
- Crosstrees - oak, 22ft long
- 4 sails - patent, 1 pair 22 shutters, 1 pair 21 shutters
- Sail span - 56ft
- Striking gear - rack-and-pinion, chain wheel partly outside body
- Millstones - 1 pair French Burr, 1 pair Derbyshire peak, underdriven
in head of mill
- Brake wheel - clasp-arm, 72 wood cogs
- Wallower - iron, 18 teeth
- Great spur wheel - iron, 64 wood cogs
- Stone nut - iron, 32 teeth
- Millstones - revolve 8 times for every revolution of the sails
- Sail speed - ideally 12-15rpm
- Fantail track - 55ft diameter
A comprehensive guide to the mill, Cromer Windmill - History and Guide
can be obtained at the mill, or via post from
The Hertfordshire Building Preservation Trust, The Castle, Hertford, SG14 1HR.
Text and images © Mark Berry,
Portions © Luke Bonwick, 1998