Tuesday 20 August 2002. We were in Norfolk today and had actually been trying to find a mechanical music museum. Which we did. It was closed on Tuesdays. So then we looked at my Tourist Map of Norfolk and Suffolk and saw that there was a working windmill nearby.
This is Billingford Windmill. It wasn't working that day. But the miller saw us drive into the empty parking spaces and came out to talk to us. As there were no particularly dangerous moving parts actually moving in the mill, he gave us the key and told us to go in and explore but not to fiddle with anything.
A windmill is full of tight-fitting solid iron cogs that would happly reduce an inquisitive finger to a smudge, so this was a bit of instruction we took to heart. We decided that rather than mess about examining each floor then climbing up some fairly steep stairs - let's call them "ladders" as we near the top floor... we would climb all the way up and then do all the puffing and panting before coming down again by easy stages.
Right at the top of a brick tower mill (which is what Billingford was) there is an iron ring on top of the brickwork on which the "cap" of the mill sits. The cap is usually if not always made of wood and resembles an upside down boat. At one end of the boat are the sails that catch the wind and work the mill.
At the other end is a "fantail", a smaller set of sails set at right-angles to the main set and which act in the same way as a weather cock on a church. They turn until the wind is coming directly at them from over the top of the cap. Attached to cogs, they continually turn the main sails directly into the wind. Hence the iron ring around the top of the brickwork and some pretty hefty wheels able to turn the whole weight of the cap.
Unless the sails are facing the wind they won't turn fast enough. Unless the wind comes from the opposite direction in which case they will turn the wrong way and cause a fire - the fate of many mills. That's what the fantail is meant to avoid. Only patented in 1745 (by Edmund Lee in Wigan) the fantail ended the task of having to continually keep watch on the wind direction and then manhandle the cap round via a pulley system or on earlier post-mills (which were totally wooden structures resting on a huge sturdy pole) by having to drag the mill around by man or horse power via a second pole sticking out at the rear.
Once the sails are turning the motion is carried into the mill itself via the axle of the sails. The pointing finger shows the shaft of the axle coming in through the cap to the topmost level of the mill.
Then the (hopefully) gentle turning of the sails is transferred by cog to a vertical shaft and the speed of rotation is stepped up quite a bit. In gales this would quickly generate far too much heat and with it the risk of fire so the sails would have some form of locking mechanism to prevent them them turning.
Still at a high level are the hoppers in which grain would be stored ready to drop down to the grinding stones. The black shaft is the main drive shaft from the cogs seen above.
The grain as seen in the right-hand hopper above. This would be delivered to the mill in sacks, hoisted up to the top levels by a crane and pulley system worked either manually or by hand. In the old days of medieval times mills were operated on behalf of the rich landowners who would charge for each sack of grain they milled. The payment was mostly by a tithe - a percentage of the resulting flour. During times of bad harvest, peasant farmers were lucky to take away enough flour to feed themselves and families.
Once the grain was released down to the mill stones, the flow had to be carefully controlled. The stones would be large flat stones with one rotating over a stationary lower stone. Grooves radiating outwards from the centre of the stone would direct the ground flour and any chunks of unground grain or bits of stone from the grinding wheels that had broken off. Literally: millstone grit.
If the grain was fed too fast between the stones this would result in the flour containing unground grain. If not enough grain was fed in, there was a danger that the stones might touch and strike sparks.
The view from the next-to-top floor level windows. The sails remained still, but when working the view would be obscured every few seconds...
Billingford Mill. It is 36 feet high (10.97 metres) and has five storeys. It dates from 1860 and cost £1,300. It replaced an earlier post mill which blew down in 1859. It can be found on the road from Harleston to Diss.
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