Tag Archives: science writing

Perfect poisons for pollinators – available from your local garden centre

We try to make our garden welcoming for bees by growing flowers that provide pollen and nectar throughout the season. We also have some unkempt areas they might want to nest in and we don’t use any pesticides. I enjoy watching the bees foraging on the flowers as they come in to bloom and currently a large cotoneaster bush is full of small bumblebees buzzing loudly as they feed in the sunshine. It’s been very exciting this year to see bumblebees and solitary bees nesting in the dry-stone walls around the garden.

When we need new plants or compost, there is one local garden centre we use. It has a good range of healthy-looking plants and a very nice tearoom! In early spring, it’s also an excellent place to watch one of my favourite bees, the hairy-footed flower bee (Anthophora plumipes), whizzing about in the greenhouses full of flowers. Earlier this year, on a sunny Sunday afternoon in late March, I noticed that these Anthophora had set up nests in the old brick wall of one of the garden centre’s buildings.

Bee 4
A hairy-footed flower bee foraging on plants within the garden centre

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About a year ago, I saw a crowd funding request from the well-known bee-defender and researcher, Dave Goulson from the University of Sussex. He wanted the money to test whether plants sold in garden centres in the UK and labelled as “bee-friendly” actually contained bee-toxic pesticides, applied during production of the plants. I remember being quite shocked to read about this possibility – could I have been buying plants to help the bees that were in fact laced with bee-toxic chemicals?

I wanted to find out more so I got in touch with our favourite garden centre and asked whether they were using neonicotinoid insecticides on their plants. They reassured me that they were not. So far so good. I then asked if their suppliers used neonicotinoids in the compost on the plants they sold. The reply came back “I’m afraid I can’t answer that question without phoning every supplier. Also a few companies we deal with import some of their stock from other European countries. I’m happy to ask my local nurseries when I’m speaking to them.” That’s the last I heard.
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Dave Goulson got his money and went ahead with the analyses. The results of his tests have just been published and they don’t make happy reading;  here is a link to his blog on the topic. He and his colleagues bought 29 pots of flowering plants from well-known garden centres around Brighton (Wyevale, Aldi, B & Q, Homebase). Many were labelled “bee-friendly” and some had the Royal Horticultural Society endorsement “Perfect for Pollinators”.

They analysed a range of pesticides in leaves and pollen from the plants and found that most of the plants contained a cocktail of insecticides and fungicides. In the leaf analysis, only 2 of the 29 plants contained no pesticides. 76% contained one or more insecticide and 38 % contained two or more. 70% of the leaf samples analysed positive for neonicotinoid insecticides, well known for their toxic effects on bees. In the pollen analysis, neonicotinoids were found at levels known to cause harm to bees. So much for “Perfect for Pollinators”.

As a result of his work, B & Q announced that from February 2018 their plants would be neonicotinoid-free. Aldi revealed that they had stopped using neonicotinoids in October 2016, a few months after Goulson’s analyses took place. Neither B & Q nor Aldi  addressed the other chemicals found in the Sussex analysis.

The Horticultural Trades Association issued a statement that I believe is both silly and cynical, basically rubbishing Goulson’s analysis. You can read Dave Goulson’s rebuttal here.
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So, it really is true that when we buy plants to help bees in our gardens from garden centres, we may be unwittingly exposing the bees to harmful chemicals, despite the “bee-friendly” labels. Also, any insect that nips into a garden centre for a feed, especially early in the season when garden centres have an abundance of flowers, may be getting a hit of insecticide at the same time.

So, what do we do if we want to have a bee-friendly garden?

Dave Goulson recommends the following course of action: if you must buy plants, buy from an organic garden centre or, failing that, go to B & Q or Aldi. Better still, grow from seed or swap plants with friends and neighbours.
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One point that has not been discussed so far concerns potential effects on humans of these pesticides found in garden centre plants. Earlier this year, I bought some fruit bushes from the garden centre and these now have a nice crop of plump berries. If these plants have been treated with pesticides, and of course I don’t know if they have, then the fruit will presumably also contain these pesticides. This possibility makes me very angry. I grow fruit in our garden so that we can eat chemical free, fresh, good quality produce. I don’t want to ingest insecticides and fungicides with poorly defined toxic effects on humans.

The featured image shows a hairy-footed fower bee feeding from plants in a lane adjacent to the garden centre

A cough medicine that really worked, and it contained opium – the story of Fudge’s Firewater

Runny nose, sore throat, hacking cough? Do you run to the pharmacy for a cough medicine that may or may not help? Until 2006, in the market town of Bridport in the south west of the UK, the locals had the luxury of a cough medicine that really seemed to work. The medicine was Fudge’s Mentholated Honey Syrup, or as the locals christened it, Fudge’s Firewater. Here is the story of this potent potion, how it came about and why it is no longer available.

Fudge 806
Mr Fudge’s Pharmacy in the late 1950s when the road was flooded. Mr Fudge is seen standing in the shop doorway with Donald Balson from the next door butchers shop in front. Photo kindly supplied by Richard Balson.

The story begins in the 1950s when Ken Fudge moved from London to Bridport to open his pharmacy in West Allington, next door to Balsons, Britain’s oldest family butchers (est. 1515). For Mr Fudge, trained in London but born in Blandford, this was something of a return to his roots. At that time, many pharmacists devised their own remedies, often to secret recipes, and Mr Fudge was no exception. He made several nostrums, as these remedies produced and sold in a single pharmacy are called, but the most popular and enduring was his Mentholated Honey Syrup (known locally as Fudge’s Firewater). When Mr Fudge retired in 1973, the recipe transferred to the East Street Pharmacy where it was sold until 2006, for much of that time under the supervision of Mr Kevin Morrish. Even now, the mere mention of the Fudge’s name evokes a warm wave of nostalgia and longing in many Bridport people.

Fudge bottle
One of Mr Fudge’s bottles (probably about 50 years old). Photo kindly supplied by Jamie Dibdin

The medicine
Fudge’s Firewater was an old-style cough medicine recommended for common winter ailments: coughs, colds, influenza, loss of voice, hoarseness, sore throat and catarrh. The dose was one teaspoon every four hours and the label warned ominously that each spoonful should be “taken very slowly”. It was sold “over the counter” without prescription but strictly under the control of the pharmacist. Fudge’s Firewater was immensely popular and many people have told me how much they trusted it to help their symptoms: “Brilliant cough mixture, couldn’t beat it”, “Amazing medicine for coughs and sore throats”, “Never bought anything else”, “Please, if there is a god, bring back Fudge’s Firewater”. People travelled long distances to purchase the medicine, holiday makers often went home with supplies and, during some winters, as many as 250 bottles of Firewater were sold each week at the East Street Pharmacy.

The medicine also had a formidable reputation: “It nearly blew your head off but by golly it did the trick”, “Tasted like red diesel mixed with the finest brandy, lovely”, “The menthol really took your breath away” “It was a trial to take but you knew it would make you better” and several people spoke of “the Fudge’s shudder”.

As Mr Fudge himself said: “Some do swear by it, some do swear at it”.

P1000282
A bottle of Fudge’s Mentholated Honey Syrup (Fudge’s Firewater). Photo kindly supplied Emily Hicks, Bridport Museum

Unconventional uses of Fudge’s Firewater
The medicine was also a voice-saver for some professional singers and I heard about one well-known entertainer who would regularly send a friend to buy Firewater from Mr Morrish to help lubricate her vocal cords. Similarly, Marco Rossi told me that, in the 1990s, when he was part of local band, Stocky Lamaar, performing in smoke-filled pubs around Dorset, he and Al, the other vocalist, each had a bottle of the potion by them on stage. With the occasional swig of Firewater, they could sing all evening without sounding like “Madge from Neighbours at a Bonnie Tyler tribute karaoke night”.

What was Fudge’s Firewater and how did it work?
Mr Fudge’s medicine was a dark brown syrupy liquid made by mixing menthol crystals and a little fudgy flavouring into Gee’s Linctus, itself an old-fashioned cough remedy dating from the Victorian era. Gee’s linctus, or to give it its proper name, squill linctus opiate, contains several potentially active ingredients.

First, there is tincture of opium, an alcoholic extract of opium (the resin derived from the seed capsules of opium poppies). The main active ingredient in opium is morphine, a substance with an established effect on cough, but also a well-known drug of abuse, and the linctus contains morphine at low levels. Squill, a plant extract, is another potentially active component in the linctus that, paradoxically, encourages coughing and mucus removal. The medicine also contains alcohol at similar levels to a fortified wine and this may have contributed to the Firewater experience. Mr Fudge’s masterstroke was to boost the effects of the Gee’s linctus by adding menthol, a remedy used for many years to help with symptoms of coughs and colds; menthol may also act as an oral anaesthetic helping with sore throats and may relieve nasal congestion.

Illustration Papaver somniferum0.jpg
The opium poppy

(from Wikipedia, for details see Link)

Although cough medicines cannot alter the course of viral infections, they may help you feel better and Mr Fudge’s medicine attacked symptoms in several ways which is perhaps why it was so popular and so successful. It was the menthol, however, that made the potion so memorable, justifying the Firewater nickname and establishing a shared experience among those who used it, believed in it and benefitted from it.

Abuse of Fudge’s Firewater
Non-prescription medicines such as Gee’s linctus, and Fudge’s Firewater, have been abused by people trying to access even the small amounts of morphine they contain. Gee’s linctus is, for example, reported to induce a “lovely euphoria and dreaminess”, but only if you are prepared to drink 50ml or more of the medicine! Local pharmacists were aware of the problem and tried to control it: Mr Morrish monitored all sales personally and Mr Conroy (manager in the early 21st century) restricted sales to one bottle per person, with a signature.

The end of Fudge’s Firewater
Gee’s linctus gradually fell out of favour as a cough medicine because of the problem of abuse. Finding commercial sources of the linctus became more difficult and temporary interruptions to the availability of Fudge’s Firewater occurred early in the 21st century. Then, in January 2006, a notice appeared on the window of Bridport’s East Street Pharmacy (then owned by Moss/Alliance) announcing that the medicine would be discontinued owing to “problems with the supply of ingredients”. That was the official line but I suspect this was not the full story. Around this time there had also been a change in the pharmacy regulations. Nostrums containing even small amounts of morphine, like Fudge’s Firewater, now required a prescription and this change must have contributed to Moss’s decision.

That wasn’t quite the end, though, because a modified Firewater was available for a few years from the St John’s Pharmacy in Weymouth, about 20 miles south east of Bridport. A Weymouth pharmacist, Mr Dipan Shah, produced and sold a version of the potion but because of the change in pharmacy regulations, people needed to persuade their doctor to issue a private prescription if they wanted the medicine. The need for a prescription severely affected sales and by 2009 production finally ceased. The change in regulations also means that Fudge’s Firewater is very unlikely ever to reappear.

Fudge’s Firewater served Bridport well for 50 years. The medicine is now just a memory but one that should be preserved as an important part of Bridport’s history.

I should like to thank Angela Alexander, Stuart Anderson, Richard Balson, David Conroy, Richard Cooper, Margery Hookings, Diana Leake, Kevin Morrish, Caroline Morrish-Banham, Dipan Shah, Elizabeth Williamson, Joy Wingfield, The Bridport Museum and the many commenters on social media who generously helped me in preparing this article.

This article appeared in a slightly modified form in the March edition of the Marshwood Vale Magazine.

The picture at the top of this post shows Mr David Conroy, manager of the East Street Pharmacy in Bridport in the early 21st century (from the Bridport News).

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For a matter of record, I have set down the timeline of Mr Fudge’s Medicine below

The Fudge’s Firewater Timeline

1950s Mr Ken Fudge opens his pharmacy at 7 West Allington, Bridport and begins production of Mentholated Honey Syrup (Fudge’s Firewater)
1973 Mr Fudge retires and the recipe for Firewater transfers to Mr Joe Sparrow at his 24 East Street Pharmacy
1975 Mr Kevin Morrish takes over the East Street Pharmacy, together with Fudge’s Firewater
1998 Mr Morrish retires and the business is acquired by Lifestyle
2001 Moss acquires the East Street Pharmacy, Mr David Conroy is the manager until 2005
2006 Moss ceases production of Fudge’s Firewater
2006-2009 Firewater available in Weymouth (Mr Dipan Shah, St John’s Pharmacy) but only with private prescription.

The Great Dorset Apple Cake Bake Off

If you want to find a traditional baker, then the county of Dorset in the south west of the UK is a good place to start. They make all kinds of artisan breads and cakes but one of their most popular offerings is the Dorset Apple Cake, a local  speciality that also graces tearoom menus throughout the county, often accompanied by a hefty dollop of clotted cream.  In 2006, the cake was voted the food most associated with Dorset and, earlier this year, the Guardian newspaper carried a feature on “How to cook the perfect Dorset Apple Cake”. 

So what’s all the fuss about and what exactly is a Dorset Apple Cake?  And can I make a Dorset Apple Cake worthy of the professionals?

Second cake

I began my Dorset Apple Cake quest by looking at recipes, hoping I might find the definitive version of this local delicacy.  I had no trouble finding recipes, indeed every celebrity chef or home baker seems to have one.  The problem is that each recipe is unique, calling for different quantities of flour, butter, sugar, eggs and baking powder, and of course apple; some also add sultanas and lemon, and many include cinnamon.   So, there is no definitive recipe and all we can say is that the Dorset Apple Cake is a rich cake containing apple.

I also found two older recipes, one from 1925 (Miss Hetty King) and another from 1932 (Miss Annette Vipan, North Chideock).  These are simpler than many modern versions but include plenty of apple, probably reflecting local ingredients.   There is also a reference to apple cake in a poem, Father Come Home (1834), by the Dorset dialect poet, William Barnes, and I suspect that apple cakes have been made in Dorset for a very long time.

Why Dorset?

Apples

Most apple growing counties in the UK make some kind of apple cake and I came across recipes from Somerset, Devon and Kent as well as further afield.  There is some variation, for example cider is often included in the Somerset cake, but for the most part, these cakes resemble the Dorset version. So why has Dorset Apple Cake come to dominate, capturing the imagination of celebrity chefs and home bakers and featuring in the Guardian newspaper?  I asked local bakers whether they knew what set the Dorset version apart but they just shrugged their shoulders.  I came to the conclusion that Dorset Apple Cake has been made in the county for many years by local people but has recently acquired a certain mystique, partly through the appropriation of the cake as the county food and partly with the enhanced foodie profile of Dorset.

I visit the experts

Leakers 2

My next stop was Leakers, a well-known, traditional bakery in the west Dorset town of Bridport.  As well as making its own version of Dorset Apple Cake, Leakers has sponsored the Best Dorset Apple Cake competition at the local Melplash Show so they should know a thing or two about the county’s signature food.  Although the business is now owned by Caroline Parkins, the apple cake is made by Jo Leaker, grand-daughter of George Leaker who moved from Devon in 1914 to take over the Bridport bakery.  Jo has been making the cake at Leakers on a part time basis for ten years using a recipe dating from 1914 “handed down and tweaked”.  I met Jo in the bakery at the end of a baking day and found her standing proudly by six large trays of apple cake, each a mosaic of rich chestnut brown cake and pale green apple chunks.  She was very welcoming and keen to share her knowledge, providing this didn’t extend to the recipe!  “Many people have tried to get hold of it!” she told me.

Jo Leaker 1
Jo Leaker with her very popular Dorset Apple Cake

Jo described her cake as “rough and rustic with lots of apple”.  She uses eaters or cookers, whatever is available, peeled and roughly chopped within the cake while the surface is decorated with chunks so the apple taste comes through; cinnamon is included but no sultanas or lemon.  Her cake is very popular, it’s now a Leakers speciality, and in the peak season she makes twenty trays a week.

The Great Dorset Apple Cake Bake Off

Inspired by my visit to Leakers, I decided to try my hand at making apple cake.  I made two versions: one according to the Guardian’s “perfect” recipe which, aside from the usual ingredients, used wholemeal flour and Cox’s apples; my second cake had less sugar and butter and was based on a recipe from Amanda Persey’s book of “Favourite Dorset Recipes”.  I used cooking apples, added cinnamon and decorated the top with apple chunks.  Details of these recipes are given below.

Cake Science

While the cakes were baking, I couldn’t help pondering the seemingly magical transformation taking place in the oven. What chemical changes were occurring as the cake baked and how does each ingredient contribute to the structure, lightness and flavour of the final product?

Every baker wants their cake to be light and airy but it needs some structure as well and here the flour is a major contributor.  Proteins in the flour come together to make gluten when they meet moisture; the gluten forms a protein scaffold, a flexible web that helps trap carbon dioxide and water vapour as the cake expands.  The lightness comes from the raising agent, baking powder; during the early phase of baking it releases carbon dioxide gas which becomes trapped within the matrix of egg, butter, sugar and flour causing the mixture to expand and giving the cake a light, porous texture.  Butter brings flavour and richness as well as restraining gluten formation helping to keep the texture light.   The eggs provide moisture and the egg proteins solidify during baking, sealing off the bubbles of carbon dioxide; the structure of the cake is completed by the coagulation of the flour proteins.

Second cake
My second apple cake

 

The winning apple cake

Armed with two of my own cakes and a chunk of the Leakers version, I asked my home tasting panel which they liked best.  The Guardian “perfect” cake looked good and had a light open texture, but everyone in my household found it too sweet, so much so that it overpowered the taste of the apples.  It might work better with a tart cooking apple but it definitely was not to our taste.   My second cake also looked good and the apple chunks gave it an appropriately rustic feel.  We liked this cake with its dense but crumbly texture; it was not too sweet, allowing the apple taste to come through strongly.  Jo Leaker’s apple cake was, however, the winner and it was especially good when warmed.  We liked its very moist but dense texture and its strong apple taste, combined with a not-too-sweet crumb and an interesting buttery surface.   I should have realised that the professionals know best!

Now it’s your turn to get baking and discover the mysteries and the pleasures of Dorset Apple Cake.

cake
Jo Leaker’s Dorset Apple Cake

 

 

Recipes for Dorset Apple Cake

My first cake

slightly modified from Felicity Cloake’s Perfect Dorset Apple Cake Recipe

Ingredients:

Wholemeal flour (225g) (I used spelt flour)

Baking powder (2 tsp)

Pinch of salt

Mixed spice (1tsp)

Rapadura sugar (175g) (Felicity Cloake calls for light muscovado which may work better)

Butter, melted (150g)

2 large eggs, beaten

4 medium Cox apples, cored but not peeled, then diced (The apple flavour may come through better with a tart cooking apple, but I followed Felicity’s suggestion of Cox’s)

Demerara sugar to top

Flaked almonds (2 tbsp) for top

 

  1. Combine the flour, baking powder, salt, spice, and sugar in a bowl.
  2. Stir in the butter and eggs and beat together for a minute or so until combined well.
  3. Stir in the apples until well distributed, then spoon the mixture in to the tin (circular tin, 20 cm diameter, with paper liner).
  4. Smooth the top and sprinkle with the Demerara sugar.
  5. Bake for an hour at 160 oC,
  6. Add the almonds and bake for a further 15-25 mins until coming away from the tin. (my cake needed more time overall so you may need to test with a skewer until it comes away clean)

 

My Second Cake

Modified from Amanda Persey “Favourite Dorset Recipes”

 

Ingredients:

Plain flour (115g)

Spelt flour (wholemeal) (115g)

Baking powder 2tsp

Butter (115g)

Rapadura sugar (115g)

Cinnamon (1tsp)

One egg, beaten

Natural yoghurt (1 tbsp) (this was an addition suggested by Hazel to make the cake more moist, it could have taken more)

Cooking apples, peeled and cored (225g roughly chopped (in the cake), 90g chunks (each chunk about one eighth of one apple) for the top))

Melted butter for brushing the top

 

  1. Mix the flours and baking powder and rub in the butter by hand until is resembles bread crumbs.
  2. Mix in the sugar and cinnamon.
  3. Add 225g of roughly chopped apple
  4. Mix in the beaten egg and the natural yoghurt and stir well until mixed evenly
  5. Put the mixture in a cake tin (circular tin, 20 cm diameter, with paper liner) and smooth the surface
  6. Press apple chunks (90 g in total) in to the surface
  7. Brush surface with melted butter
  8. Bake at 170 degrees for 30-40 min until surface is firm to touch or a skewer inserted in the cake comes away clean. The recipe calls for 30-40 min but I had to cook for longer, it will depend on your oven.

Still ticking after all these years – the Ottery St Mary Astronomical Clock

Ottery St Mary is a small town in East Devon in the south west of the UK. The town has several claims to fame: not only is it the birthplace of the poet Samuel Taylor Coleridge but Harry Potter fans will know it as the inspiration for Ottery St Catchpole, home of the Weasleys. Then there is St Mary’s Church, a magnficent building, a mini-cathedral. There is much to see within the church but one of its more unusual features is the ancient astronomical clock. As well as telling the time, it also shows the age and phase of the moon, and it has done so for more than five centuries. This beautiful clock is a rare example of medieval craftsmanship and gives us a unique insight into life many centuries ago.

St Mary's Church Ottery St Mary 3
St Mary’s Church, Ottery St Mary

 

Perhaps there is a chiming clock in the town where you live that insists on telling you the hour. You probably also wear a wristwatch and, failing that, your computer or phone provides minute by minute updates of the time. But it hasn’t always been like this, so how were clocks developed and how did time come to rule us?

The earliest clocks

In Western Europe, the first rudimentary clocks began to appear only during the medieval era. They were the preserve of monasteries and their purpose was to provide a signal to the sacristan who then rang the cloister bell, calling the monks to prayer at regular intervals. These simple timepieces were probably water clocks, where time was measured via the flow of water in to or out of a vessel. Although they were not very accurate, they were a great improvement on sundials in a cloud-prone country.

Then, in the late 13th and early 14th centuries, a major breakthrough in clock development occurred. Reports of new mechanical clocks began to appear from various places in Europe including Exeter (1284) and Salisbury (1306) and, most likely, this coincided with the invention of the escapement. These new clocks would probably have been driven by a weight attached to a rope wound round a drive shaft. The escapement was a device that enabled the weight to descend in a stepwise manner, each step representing the passing of time which could be displayed on the clock face. The familiar “tick, tock” of these clocks is the sound of the escapement. So began a new era of mechanical clocks composed solely of metal wheels and gears. These clocks were enthusiastically installed in church towers and other public buildings allowing a bell to be rung at intervals throughout the day, broadcasting time to the inhabitants of the town and, for example, signalling the opening of trading at the market.

As these mechanical clocks became more sophisticated they were elaborated to show not only time but also the age and phase of the moon. The south west of England has four well preserved examples of these ancient astronomical clocks that have survived for at least five centuries, perhaps because of their novelty or their beauty. They are to be found in Exeter Cathedral, Wells Cathedral, Wimborne Minster and in Ottery St Mary Church.

The Astronomical Clock in St Mary’s Church, Ottery St Mary

The clock hangs high above the south transept and below the bell tower. Its bright blue face, about a metre and a half square, is liberally decorated with gold and red and topped with a gold angel blowing a trumpet. Unashamedly beautiful and garish at the same time, it dominates the scene.

Astronomical Clock in Ottery St Mary Church
The astronomical clock in St Mary’s Church, Ottery St Mary

 

The clock has two circular dials. The outer dial shows the hour with two sets of twelve Roman numerals. A golden sphere, representing the sun, moves to show the time. The inner dial contains thirty Arabic numerals with a gold star moving between them to show the age of the moon. Within the inner dial is a sphere painted half white, half black which rotates on its axis once every 29.5 days depicting the moon and its phases; the moon sphere also moves around the dial once every 24 hours. A black sphere at the centre of the clock shows the earth as the centre of the universe. The clock mechanism is visible behind the face.

Clock Mechanism Ottery St Mary
The clock mechanism

 

The exact age of the clock is not known but we may get a hint from the strong similarity between the Ottery St Mary clock and the astronomical clock in Exeter Cathedral, which dates from the 15th century. Also, both timepieces depict a medieval view of the structure of the universe where the sun rotates about the earth. This model was only superseded in 1543 when Copernicus proposed that the earth actually rotates about the sun, so we can be fairly sure that both are older than this date.

Astronomical Clock in Exeter Cathedral
The astronomical clock in Exeter Cathedral. The Latin inscription translates as “The hours pass and are reckoned to our account”.

 

Why astronomical clocks?

It is easy to understand the purpose of a clock that broadcasts the time of day to a busy town but why would the medieval clockmaker go to the trouble to include information about the age and phase of the moon and the apparent movement of the sun about the earth? One possibility may have been a desire of the contemporary Church to create a model of God’s celestial universe but perhaps there were secular reasons as well. For example, knowledge of the phases of the moon would have been useful in planning a long journey at night or a meeting in winter. Also, because of the influence of the moon on tides, knowledge of the state of the moon would have been useful for seafarers.

When they first appeared, these clocks must have seemed miraculous: man had constructed a machine that would predict the motion of the sun and moon and show the hours of the day. Possession of such a clock would have been a source of civic and ecclesiastical pride and conferred distinction on a town. For Ottery St Mary, perhaps it was considered fitting to install such a clock in its “mini-cathedral” of St Mary’s church.

The 21st century observer, surrounded by technology and gadgets, might, however, simply view the Ottery St Mary clock as an ancient curiosity. This would be a mistake: the clock is a rare example of advanced medieval craftsmanship as well as offering considerable insight into how life was lived so many years ago. It is a true medieval marvel.

 

This article appeared in the November edition of the Marshwood Vale Magazine.

The colours of a Dartmoor Sunset

Last week, on a clear, warmish evening, we went up to Haytor on the south eastern corner of Dartmoor to watch the sunset.  Haytor consists of two huge outcrops of granite, one larger, one smaller, set on a hill some 450 metres above sea level. The two huge outcrops of granite are a local landmark visible for miles around, and the position of the Tor affords panoramic views across the surrounding countryside.

Haytor contrails
Approaching the larger of the Haytor rocks from the east; contrails in the sky

 

A wide, grassy track led steeply up to Haytor from the car park. The sun was setting directly behind the great granite outcrop that evening so the path and the surrounding countryside were in shadow, bathed in an eerie twilight.  Stands of yellow gorse and vivid purple bell heather lined the path and a few crows pottered about on the track ahead of us.  The rock itself was a flat grey in this light but, behind it, the sky was a luminous pale blue engraved with contrails left by passing aircraft, brilliant white shooting stars.  Turning to look back, there were long but slightly hazy views across rolling countryside to Newton Abbot and on to the sea more than 10 miles away at Teignmouth.  Much of this land was still illuminated by the sun and we could see woodland, small towns and the white scars of clay mine workings.  Increasingly, however, a portion of the land lay in shadow as the sun set.

Eastern view
The view to the east from Haytor towards the sea

 

Heather and gorse
Heather and gorse

 

Under the eastern flank of the larger rock, shadow dominated and the air was cool but upon reaching the western side it was as though we had entered a different, more optimistic world – a world of orange light, brightness and warmth.  The sun was still some distance above the horizon but its low rays created a curious moonscape on the nearby moorland.  Every tussock of grass and every craggy stone were illuminated along with the occasional sheep; every object cast a long shadow.  The rich light lent a warm glow to the grey Haytor stone probing every crack, crevice and fissure.  Two German children and later, several local lads in reverse baseball caps clambered in to an alcove in the rock to enjoy the view.  One or two small birds tracked across the landscape together with a lone bee returning to its burrow. In the distance the western hills acquired an apricot halo.

Dartmoor moonscape
Dartmoor “moonscape”

 

Moonscape on Haytor
The smaller of the Haytor rocks with the “moonscape” created by the setting sun

 

As the earth turned, the sun continued to approach the horizon but for some time, corresponding changes in the landscape were slow.  Looking back to the east, increasing amounts of land were enclosed in shadow, and, around the Tor, shadows lengthened.  The colour of the rock changed slowly from a warm pale brown at 20.00 to a deep reddish brown over the next twenty minutes.

Haytor rock 2002
The larger Haytor rock at 20.02

 

Then events seemed to accelerate and I detected a change in the light level as if someone were turning down a dimmer switch.  I suppose the sun had begun to dip below the horizon but it was difficult to be sure as it was still too bright to look.  Shadows became longer still and the rock took on a pinker almost red hue, not unlike the colour of the stone used in some of south Devon’s older buildings.  For a few minutes, the sun painted the landscape surrounding the rock in the surreal colours of pink and a luminous green.

Haytor rock 2024
The larger Haytor rock at 20.24

 

Haytor rock 2027
The larger Haytor rock at 20.27

 

The colour of the rock continued to change and by 20.25, with the sun about half way below the horizon, (based on a photograph), the colour lost its warmth as if it were being drained away.  By 20.26, grey started to insinuate and a minute later the sun had disappeared.  The rock was now a uniform grey and the sun had set.

Sunset Haytor 2027
The western view at 20.27

 

All that was left on the western horizon was an orange glow above the hills, a memory of the sun, with increasing apricot fringes either side.  Overflying aircraft and their contrails were now tinged with pink and, above all this colour, the sky was a very washed out, pale blue.

Eastern view 2

 

We walked back to the car in the half light, the air cooler now.  Ahead of us and in the distance, the eastern hills were bathed in a hazy dark blue light that extended above the land for a short distance.  Above this blue layer was a distinctive red layer that shaded to orange and yellow before merging with the clear blue sky above.

A white moon, almost full but not quite, now hung in the sky like a ghostly eye.

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I’ve seen many impressive sunsets but I don’t recall ever being able to follow the changes so clearly.   What we witnessed that evening was a spectacular natural phenomenon, a celestial light show.

But can we understand how all these colours arise?  The explanation comes from considering the position of the sun at different times of the day and the effect of the earth’s atmosphere on the sun’s light.

Although the light coming from the sun is white, we know from looking at rainbows that it is in fact composed of light of different colours (red, orange, yellow, green, blue, indigo, violet).  These colours of light have different physical properties that mean that they respond differentially when they meet particles in the atmosphere.

For much of the day, the sun is roughly overhead and as its light travels through the earth’s atmosphere it encounters molecules in the air (nitrogen and oxygen mainly) and some of the light is scattered during this encounter.  The blue light, and the violet, are scattered more than the other colours and our eyes preferentially detect this scattered blue light; this gives the sky its colour.  Because a small part of the blue light is lost through this scattering, sunlight appears slightly yellow rather than pure white.

When the sun is very low in the sky, towards the end of the day (sunset) and also near the beginning (sunrise), sunlight has to travel much further through the atmosphere.  Blue light is scattered as before but, because there is so much more atmosphere to traverse, the blue light is eventually lost, so that red and orange colours dominate at sunset and sunrise.

 

But what about the colours in the eastern sky?  The layer I described as “hazy dark blue light” was actually the earth’s shadow, where our planet casts a shadow on the atmosphere as the sun sinks below the horizon.  As the sun falls further, this shadow layer increases, only to disappear eventually in to the deepening blue of the night sky. The red layer goes by the wonderful name of the Belt of Venus and arises from residual sunlight encountering dust particles in the atmosphere.  These particles scatter the light (red by now) backwards.

 

Thanks go to Hazel who had the idea for sunset watching.

The surprising story of oil in Dorset.

A few months ago, I visited Kimmeridge Bay in Dorset in the south west of the UK.  I went  to look at the oil well on the cliffs above the beach and wrote about my experience.  The Kimmeridge oil reserve is quite small but further east there are huge additional reserves of oil extending for several kilometres under Poole Harbour and Poole Bay.  I wanted to write about these much larger deposits and the environmental effects of extraction: my article, which also takes another look at some of the Kimmeridge story, appeared in the May edition of the Marshwood Vale Magazine. Here is the article:

It’s difficult to believe but one of the most beautiful parts of Dorset in the south west of the UK is home to the largest on-shore oil field in Western Europe. And yet the day to day impact on most residents and on the local environment is minimal. Perhaps the Dorset oil experience can help us predict the potential environmental effects of shale gas extraction by fracking in other parts of the UK? Let’s look at the story of oil in Dorset and see what we can learn.

“Kimmeridge Coal”

Medieval times were harsh for most people but if you lived near Kimmeridge Bay in the Isle of Purbeck, you had one thing going for you; some of the rocks exposed in the cliffs would burn so you had a ready-made fuel for heating and cooking. The locals called it “Kimmeridge Coal” and it didn’t matter that it smelt awful, it was available and it was free. The same logic drove Sir William Clavell in the 17th century to set up alum works at Kimmeridge using the fuel. His efforts came to nothing because of patent restrictions so he turned to making salt by boiling sea water and subsequently he set up a glass works, but neither enterprise prospered.

“Kimmeridge Coal” is found in bands of bituminous shale in the cliffs around Kimmeridge Bay but further exploitation of the material had to wait until the 19th century when it was realised that useful hydrocarbons might be extractable. Processing plants were set up at Weymouth and at Wareham making varnish, grease, pitch, naphtha, paraffin and paraffin wax and in 1848 the street lights of Wareham were lit by 130 lamps powered by gas derived from the shale. The industry never prospered, possibly because the high sulphur content made the gas unsuitable for domestic use.

Kimmeridge oil shale is a useful material but it is not a source of conventional crude oil. Ironically, the first discovery of crude oil in Dorset also occurred at Kimmeridge Bay but it comes from rocks lying well below the shale deposits.

The Kimmeridge “nodding donkey”

Oil pump
The Kimmeridge nodding donkey

The search for oil in Dorset began in the 1930s but it was not until 1959 that the first well producing oil and gas was discovered below Kimmeridge Bay. The well is extracted by a single beam “nodding donkey” pump on the cliffs above the Bay that has worked continuously for more than 50 years; it is the oldest working oil well in the UK and the “nodding donkey” is now part of the local scenery. The Kimmeridge well produced 350 barrels of oil a day at its peak but this has now declined to a fifth of that level. Although the Kimmeridge reservoir is not large, the discovery prompted the search for other oil deposits in Dorset.

The largest on-shore oil field in Western Europe – hidden near Poole Harbour

The energy crises of the 1970s led to further exploration in Dorset and in 1974, oil and gas were discovered by the Gas Council at Wytch Farm on the southern side of Poole Harbour. Production started in 1979 and nowadays the Anglo-French company Perenco owns the majority stake in the oil field. There are three large reservoirs of oil 1-2 km below the sea, extending up to 10 km under Poole Harbour, Brownsea Island, Sandbanks and to the south of Bournemouth. Peak production was in 1997 at 110,000 barrels of oil per day; current levels are about 18,000 barrels per day. The field also produces natural gas (for domestic use) and liquid petroleum gas.

nodding donkeys Wytch Farm
Some of the Wytch Farm nodding donkeys (photo courtesy of Perenco)

 

Furzey Island
Furzey Island in Poole Harbour showing the “hidden” oil wells (photo courtesy of Perenco)

 

There are 12 well sites distributed around Wytch Farm, the Goathorn Peninsula and Furzey island from which more than 100 wells have been drilled. There is also a gathering station where the products of the wells are collected, processed and distributed. This is a large industrial enterprise, the largest on-shore oil field in Western Europe and the second largest consumer of electricity in the South of England (after Heathrow Airport).

Hengistbury Head looking west
Poole Bay viewed from Hengistbury Head – oil reservoirs and long distance drills extend under the sea 1-2 km below the surface (from Wikipedia).
The paradox is that this industrial complex operates in an Area of Outstanding Natural Beauty so the site has been developed with this is mind. Buildings are on sites that have been excavated to reduce height and are screened by trees. Facilities are painted a dull brown and the number of well sites has been minimised by drilling long distances horizontally away from the well site in to the oil deposits; until 2008 Wytch Farm held the world record for the longest drill extending 10.1 km under Poole Bay. In consequence, this large industrial complex has minimal impact on the surrounding countryside and most people are unaware of the activity.

Goathorn Peninsula
An oil rig on the Goathorn Peninsula used for long distance directional drilling (Photo from Wikipedia, taken in 2006) .

 

Lessons from Dorset oil

Wytch Farm is a great success story, both in terms of the oil and gas produced and the minimal environmental impact. Some have used the Wytch Farm experience to suggest that fracking (hydraulic fracturing for shale gas) in other parts of the UK will also have a minimal environmental impact, even suggesting, incorrectly, that fracking has already occurred at Wytch Farm.

Although similar drilling technology is used to extract crude oil and to release shale gas, fracking uses large volumes of high pressure liquid (mostly water) to create fissures in low permeability rock and this has not been carried out at Wytch Farm. Also each potential fracking site is likely to be unique and different from Wytch Farm in terms of the density of wells required, the density of population and the nature of the countryside. Dorset oil has been managed to minimise environmental impact but it would be wrong to use the Dorset oil experience to predict the general environmental impact of fracking elsewhere.

There is, of course, one important issue I have not considered here:  should we continue to extract and use oil given the need to prevent global climate change?  Take a look at the complementary article for my views on that.

Renewable energy from a Devon river – the new Totnes Weir Hydro

About a mile upstream of the south Devon town of Totnes, the tree-lined tranquillity of the river Dart is interrupted by a weir. Water cascades over this concrete barrier and after heavy rain there is a spectacular display of power with swirling whirlpools and foamy white water. Slate-grey herons and sparkling white egrets stand sentinel by the weir and the occasional grey seal lurks below, waiting to feast on fish that linger too long. There has been a weir at this bend in the Dart since the 16th century, built originally to harness the power of the river; the present rather bland construction dates largely from the 20th century.

Totnes weir
The Totnes Weir viewed from the upstream pool. The picture shows the concrete weir after the installation of the new Hydro (off the picture to the right) and after a period of low rainfall so that water flow across the weir is quite low. The gulls are enjoying the calm conditions.

 

The weir is a downwards-sloping concrete barrier that interrupts the flow of the river so that a large pool of water accumulates upstream, isolated from the tidal downstream water about three metres below. This pool of water is a store of potential energy that was used in the past to drive several water mills in the town a mile away. A channel, the leat, ran from the pool all the way in to Totnes and providing the leat stayed above the level of the river it contained the energy to drive a water wheel. Only one mill building now survives: the Town Mill dating from the 17th century but with 19th century additions. This was used as a water mill until 1945 and currently houses the Tourist Information Centre. The leat is still intact and can be viewed along much of its path, through an industrial estate, under the main railway line and passing near the front of Morrisons superstore. The leat is celebrated in the name of the town’s large medical centre, the Leatside Surgery.

Water Mill
A water mill at Dartington in Devon showing the principle of the leat. The leat takes water from the stream and providing the leat stays above the stream it can drive the mill wheel.

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Turbine Building exterior
The turbine building of the Totnes Weir Hydro. The Archimedes Screws can be seen on the right.

 

Hydro and weir
The two Archimedes Screws alongside the weir

 

Over the past year, a neat, stone-clad, turf-roofed building has materialised by the side of the weir. This is the turbine house of the new Totnes Hydro which once again harnesses the power of the Dart. On the downstream side of the building are two tube-like structures roughly aligned with the descending surface of the weir, each tube containing an Archimedes Screw. Water from the pool behind the weir passes under the turbine building to enter the tubes, pressing on the blades of each Archimedes Screw causing them to turn and driving the turbines. The Archimedes Screws can be viewed from the downstream side and I find them mesmerising – turning steadily, water splashing, feeling almost alive – as they transform the potential energy of the water in to kinetic energy and subsequently electrical energy.

turbine in action
Renewable energy in action: a close up of water emerging from one Archimedes Screw.

 

When there is a good head of water, the turbines generate about 250 kW of power.  Output will depend on flow in the river (higher power after heavy rain) and the head across the weir (typically about 3m but reduced by spring tides).   Generation may cease altogether for about two weeks in a dry summer when water flow in the Dart is low.   Currently, the electricity generated is powering the local comprehensive school and an aluminium foundry on the nearby industrial estate and any surplus enters the grid.  To put this in to perspective the overall energy produced is enough to power the equivalent of about 300 homes. In time, the hydro will also provide electricity for the new ATMOS project.  This is a community-led development of homes and businesses on the former Dairy Crest site in Totnes.

The river Dart is an important route for migrating fish and the weir already contained a fish pass to help sea trout and salmon overcome the barrier. The pass was, however, in poor condition so that fish were having difficulty moving up the weir leading to losses to hungry herons and seals. The new Hydro project includes renovating the existing fish pass and building an additional modern fish pass alongside the turbine building. These should help migrating fish so that, in time, the piscine population on the Dart increases; new fish counters have also been installed to help monitor traffic.

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So far so good, but if equipment is installed to capture the energy of the river it is bound to alter the flow over and around the weir.   You can see this clearly on the upstream side of the turbine house where water in the pool flows towards the new building to enter the Archimedes Screws, eventually discharging in to the river below.   Although water flow through the turbines is carefully regulated by sluices to make sure that the weir does not dry out, less water now flows across the weir than before.  This redistribution of water has remodelled islands in the river downstream and night fishermen have had to relearn safety on the river.    We should not forget, however, that when the weir was first built and water was directed down the leat to power the Totnes mills some 500 years ago, water flow in the river must have been changed to a much greater extent.    There is also the question of noise.  The new Archimedes Screw turbines do emit noise as they turn and there is some splashing of water.  The turbine building is insulated and the current level of noise from the new installation is no more than I can remember coming from the weir on a full flood.

Water enters hydro
The pool of water behind the weir showing water preferentially entering the turbine building.

 

The Weir Hydro project was developed by the owners of the weir, Dart Renewables, working closely with the Totnes Renewable Energy Society (TRESOC). TRESOC was set up by local residents to enable the community to develop renewable energy and to retain control of the resources. On a practical level TRESOC aims to supply local homes and businesses with “local” energy. If everything works to plan, the Totnes Weir Hydro should generate 1.35 GWh of electricity each year, saving 550 tonnes of carbon dioxide. The majority of this electricity will be used to power local enterprises.

Disclaimer: I am a member of TRESOC and have invested in some of their projects.