The main attraction at Woodbridge, for bread-heads at least, is the Tide Mill. And when the tide goes out, something magic can begin. That's because on the landward side of the mill buildings there is a pond which floods at high tide. The sea water goes straight through the mill, under the water wheel and into the pond.
At high tide the miller craftily closed the gate at the seaward side of the pond, trapping the water inside. Once the tide goes back out to sea, the miller can open the gate and allow the pond water to follow it, at a steady pace, driving the water wheel as it goes.
Et voila - the mill starts to turn. Here you can see that the tide is well out, but the wheel is turning clockwise as the water from the pond flows under the wheel, from right to left in the picture, following the tide out to sea.
This is the pond water that has just flowed through the water wheel and is now on its way back out to sea.
Unlike the Heron Corn Mill, where the water hits the wheel at the side, high up (a high breast shot wheel) the water at Woodbridge hits the wheel at the bottom (an undershot wheel).
Undershot wheels use a flat water source like a stream and are simply pushed along by the flow of water. As you can see in the picture below, the Tide Mill just has boards on the edge, which the flow of water pushes against. This is a very old and simple design, but it is not very efficient.
Breast shot wheels exploit a drop in the water level such as a waterfall or weir. As you can see in the picture below, the Heron Corn Mill wheel has buckets on the edge, to hold onto the falling water and make use of the potential energy it contains.
To digress slightly into philosophy, in chapter 2 of Ulysses, Stephen is thinking about the nature of events, and this idea from Aristotle comes to mind, as he ponders why one thing happens and not another -
It must be a movement then, an actuality of the possible as possible.
When something happens, there is a position before and a position after. The event is the movement from one position to the other. Water coming down a waterfall where there is no water wheel (one possibility) releases its potential energy by landing with a great slap on the lower level. Water coming down a waterfall where there is a water wheel (another possibility) expends its potential energy by turning the wheel and landing gently on the lower level. Which possibility becomes actual depends on whether there is a water wheel there or not. But the amount of energy expended is the same in either case.
End of digression.
Once the water wheel starts turning on the outside of the Tide Mill, so does everything on the inside. Woodbridge has a fine set of largely wooden machinery, and lots of wooden teeth - not cheap to replace when they get broken. Much like my own teeth, come to think of it.
As in all mills, there are plenty of belts passing power on from one wheel to the next, applying the power from the water wheel wherever it can be made use of.
This set of steps didn't have much head room to spare so the Tide Mill have made appropriate use of modern technology and installed a sensor on the steps which activates a loudspeaker when you walk past. A little voice from behind you helpfully warns "Mind yer 'ead, mate!"
And when you turn round to thank whoever tipped you off, you find it was Cardy McCardboard Face all along.
Here you can see the feed from the top floor, where the bulk grain is stored, into the hoppers over each set of stones, from there into the shoe, and finally a sprinkle at a time into the eye of the runner stone. You could think of this as a microcosm of the whole supply chain for food. The top floor is the supermarket's distribution depot, the hopper is the supermarket, the shoe is the kitchen cupboard and the damsel is the cook weighing out a cup full of flour at a time to cook with.
These beam scales are like a set at Eskdale Mill in Boot. The Heron Corn Mill does not have such a heavy duty scale as this one.
These are the scales at the Eskdale Mill.
The Tide Mill's grain hoist is also heavy duty, with a chain instead of a rope, and going right to the top of the building.
As the notice board explains, this is powered from the crown wheel at the top, along with other labour saving devices.
Te handle in the picture below is the fine tuning device which raises or lowers the runner stone to alter the coarseness of the flour.
And when you want to turn the Tide Mill off, you just close the pond gate and stop the flow.
The old bushel and half-bushel measures below date back to 1824.
The notice helpfully explains that a bushel is a measure of grain by volume. The bushel shown here was probably a Winchester bushel, which measured 18.5 inches across and 8 inches deep. My schoolboy maths suggest that means that a bushel is roughly 2150 cubic inches.
Schoolboy workings:
The area of a circle is Pi * (the radius squared), and the area times the depth gives the volume, so Pi * 9.25 * 9.25 * 8 = 2150.
2150 cubic inches is roughly one and a quarter cubic feet. If you are too young to understand a word of that, you could fit about 28 bushel in a cubic metre.
The notice also suggests the weight of a bushel of grain might be 56 lbs or 80 lbs, which is a sack or a sack and a half of potatoes. I doubt very much that you would fit 28 sacks of potatoes in a cubic metre, which suggests that a bushel of grain is considerably heavier than a bushel of potatoes. Not something you would want to pick up on your own, anyway!
The second notice moves from lbs to kgs, but the message is similar. Eight bushels makes a quarter which is about 230 kg or 506 lbs. So a bushel by this calculation is about 63 lbs, or a little over a sack of potatoes.
The notices generally are full of good clear information. The Tide Mill uses traditional French burr stones with a familiar pattern of furrows.
And I didn't know this about angle grinders!
The Tide Mill can trace its ownership back to 1170, right through to auctions in 1811 and 1968 and the setting up of the trust in 1977. So the start of the modern phase of the Tide Mill's history starts about the same time as the first phase of restoration work at the Heron Corn Mill.
The damsel is one invention that every mill uses. Whoever dreamed it up really earned his bonus that year, but I often wonder how many millers over the years have been driven up the wall by the regular tap, tap, tap of the damsel against the end of the shoe, as it encourages a few grains at a time to drop into the eye of the runner stone.
Millers love gadgets, especially if they can reduce the stress level of the job. There's nothing worse than constantly having to keep an eye on something. The bell does that job with the level of the grain in the hopper. When most of the grain has been fed into the stones, the bell rings and gives the miller a five minute warning to throw in another sack of grain. At the Heron Corn Mill, you can hear when the grain is getting low, because the mill speeds up. When the next bag of grain goes in, everything slows down again. But a bell would be nice.
Again the miller would always be looking to automate heavy jobs. If the water wheel can hoist a sack of grain up to the top of the mill, the miller certainly won't be carrying it up on his back! And what better than gravity to bring the finished product down again? At the Tide Mill, the stones are at floor level, and the flour ends up being collected in sacks on the floor below. This is the more usual arrangement, but it doesn't work like that at the Heron Corn Mill. Our stones are raised up on the lauder frame, and the flour comes out into sacks on the same floor as the stones. This design is quite local to our area, and makes our mill quite unusual.
I wonder what happened to this arrangement at the Tide Mill? It looks like a 1950s attempt at bringing the old place up to date, but why did they want to do that? It's the very fact that things have moved on which makes the old place worth preserving as an example of how things used to be.
Another gadget that every mill uses is some sort of temporary blocker in the flour chute. At the Heron Corn Mill we slide a piece of wood across the chute so that flour builds up behind the piece of wood. That allows the Miller time to change to a new sack when the last one is full. It looks like the Tide Mill has a hinged flap in the chute, with a string attached. Drawing up the string raises the flap and blocks the chute, stopping the flour from coming out while the miller changes the sack. I'm not absolutely sure how this works!
The Heron Corn Mill has a bin metal lined box for storing grain. The Tide Mill seems to be able to work with larger quantities, judging by the bulk storage bin on the top floor.
I had a great time when I visited the Woodbridge Tide Mill, and I can thoroughly recommend a visit if you are ever in the area. Check the web site for times when the mill will be working. This is simply dictated by when the tide is in and when it is out. You can buy their excellent very strong wholemeal wheat flour in coarse or fine form, and it makes very good bread.
Here are some short videos of the machinery turning, which I took on my visit on Sunday June 17 2018.
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