Archives for posts with tag: action potentials

In classical antiquity, a time stretching from Homer to the early middle ages, geographic orientation usually referred to landmarks or astral phenomena to determine direction. Eos, meaning dawn, and Hesperus, meaning evening, were named for sunrise and sunset with north (arctos) being marked by the constellation Ursa Major and later the Pole Star. The winds also became associated with direction and named in accordance with their qualities such as hot and humid or cold and dry.

The number of points on a wind rose began with the four cardinal points that were added to and refined over time. Aristotle designed an asymmetrical 10 point wind rose for “the study of things high in the air” (meteorology) which was later refigured by Timosthenes, a 3rd century BCE Admiral and geographer, naming a system of twelve winds and using this as a tool for navigation. The contemporary compass has its roots in the ancient classification of winds.

Freshly excavated. A new tablet for the series Instruments of the Anemoi, replacing a previous one based on the idea of a wind rose and set with etched copper markers, the designs of which are influenced by characteristics of the gods (anemoi) represented by each of the twelve winds.

Instruments of the Anemoi are a set of dodecagon tablets cast in Snowcrete, a cement with no magnetic minerals, as is used for instrument pedestals at a magnetic observatory. They also respond to a twelve sided anemoscope “table of the winds” carved in marble around eighteen hundred years ago and held at the Vatican Museums. Releasing the cast from the mould and collagraph is a rewarding process – if all the pieces have held their position during the concrete pour and vibrating to release trapped air bubbles. Luckily this time was a success.

The other two sculptures in the series. A hand beaten copper bowl with a ‘silver fish’ floating in water based on the oval shaped compass needle illustrated in Breve Compendio de la Sphera de la arte Navegar by Martin Cortes 155. Wafer thin fish shaped iron leaves were also used by 11th century Chinese geomancers. Nails and iron filings reveal an embedded magnetic field and hark back to a legend on the discovery of the lodestone, a naturally magnetic mineral, which recalls a Greek shepherd who noticed the nails in his boots were attracted to the rock beneath his feet.

Unsettling to find it is already one year on since A Stone Sky duo exhibition with Julie F Hill opened at Thames-side Studios Gallery and this work was first shown.

Around 95% of the universe is ‘dark’ to us, formed of unknown and possibly unknowable matter which may be inaccessible to us, but cosmic rays offer a tangible contact with outer space.   

Giving The Breath of Stars a run to see if the cosmic rays are still there 😉 These images are stills of live action.

Cosmic ray detectors, mini computers, wooden box (20 x20 cm), video projection; live duration.

The Breath of Stars is a digital video work activated in real time by cosmic rays. These high energy particles arrive from outer space, interacting with life and technology on Earth. Coming from the heart of exploding stars or the depths of black holes, cosmic rays power across the universe with unimaginable energy. Some may come from phenomena yet to be discovered or even from other dimensions. A kaleidoscopic animation is projected every time a cosmic ray is recorded passing through the detectors. The animations are created from footage of cosmic ray trails filmed in my cloud chamber.

This cold damp weather is stimulating the moss regrowth on the apex pinnacle of The Absolute Hut (of action potential) that found a space in my garden after The Stone Sky exhibition this time last year. I had spent weeks preparing the recycled fence boards to make the North facing wall of the hut, painting them with various mixtures of buttermilk and yogurt blended with moss and was so excited when it began to grow. During the exhibition I would mist it every day. The beginning of my fascination with huts!

The Absolute Hut (of action potential) Wood, moss, paper, copper, video projection, video monitors ; 200 x 300 x 375 cm

Operating as a sensory hub where a range of actions and processes are running concurrently reflecting on the dynamics between the Earth’s geologic structure and navigation using the magnetic field. Neurons in the brain and nervous system send information electrochemically around the body. The signals they send are called action potentials, which is a temporary shift from negative to positive within the cell caused by certain ions entering the cell. Action potentials can be triggered by an interaction with the magnetic field, causing a reaction in the body.

Interference 2023 (video still)

A year on and the pyramidion that sits on top of The Azimuth Obelisk (of sedimentary knowledge) is evolving. The patination, which involved a variety of chemicals being applied to the copper in layers, is an ongoing process.

Sedimentary rock holds a geological history of the Earth’s magnetic field within its mineral components. The geomagnetic field, generated by the Earth’s molten core, varies through time; the magnetic poles migrate, go on excursions, or reverse polarity. During these periods of flux, the strength of the magnetic field changes, and this phenomenon is recorded in archaeological artefacts, volcanic rocks, and sediments. Limestone, a sedimentary rock, is often formed from crushed seashells, compressed over aeons. Crushed oyster shells were added to the obelisk base cast in Snowcrete.

This sculpture also embodies the passage of time, and a layering of information, in the months of collecting paper donations or scavenging the recycling bins, weeks tearing down the hundreds of prints and drawings into squares decreasing by 1mm every 50 sheets, drilling holes through the centre and hours to build the almost 3m stack. I’m very grateful to everyone who donated some of their work archive. These images are now secreted within the layers of the sculpture, hinted at where edges are exposed, echoing the Earth’s sedimentary knowledge.

The Azimuth Obelisk (of sedimentary knowledge) Paper, steel, Snowcrete, oyster shells, patinated copper; 30 x 30 x 270 cm

 This work is a reimagining of an ‘obelisk’ erected at Hartland Magnetic Observatory in the late 1950’s to be viewed through the north facing window of The Absolute Hut, it acts as a permanent azimuth mark from which the drift of the magnetic north pole is monitored. I am excited that this sculpture is being considered for exhibition in 2026 at the Royal West of England Academy in Cosmos: The Art of Observing Space curated by Ione Parkin with some amazing artists in the line up whose work I admire.

I first came across directional magnetic steel in the Electronic & Magnetic Materials Group open day at the National Physical Laboratory. Intrigued, I wanted to know if I could get hold of some to work with. I was put in touch with Union Steel Products who were very helpful in supplying a small amount (to them) of the material, but they import the product, and it arrives with an indeterminate protective matt grey coating. This was my challenge. It took many days of sanding and gently etching each sheet to reveal the pattern. It was a very temperamental material to work with, the pattern might appear but quickly tarnish and muddy over. So much of the work in the resulting sculpture was about the process of exposing an internal mechanism.

The dramatic Widmannstätten patterns found in meteorites due to their slow evolution through heat and pressure are also revealed through being cut, polished, and etched.

These secrets are not revealed lightly.

Domain of the Devil Valley Master

This work uses industrial directional magnetic steel, sanded and etched to reveal the Goss texture of rolled iron silicon alloy crystals. The jigsaw pattern of magnetic domains give this material exceptional magnetic properties. The simple evocation of a spiral described in geologically informed polygons draws upon many references, from the shape of our own Milky Way Galaxy sculpted by vast cosmological magnetic fields and the spiralling molten dynamo generating Earth’s magnetic field, to the inner pathway of spiritual growth and the route to the symbolic omphalos (navel) at the centre of the world where the sky entrance and the underworld meet. The title of this work originates from an ancient Chinese manual on the skills of persuasion, The Book of the Devil Valley Master, containing the first known mention of a compass, known at the time as a south-pointer. 

Work in progress. Mapping a response to the crystal structure of magnetite. Magnetite is the most magnetic of all the naturally occurring minerals on Earth found in igneous, metamorphic, and sedimentary rocks. Nano-particles are also found in the human brain, heart, liver, and spleen and the cells of many other organisms, with some creatures using this for navigation techniques.

Magnetite crystals from road traffic pollution caused predominantly by vehicle frictional braking systems can outnumber natural magnetite in the human brain by 100:1 – this is a worrying trend as these crystals could be involved in our perception, transduction, and long-term storage of information in the brain.

Returning to my conversation with Alan Watson on the history of Haverah Park Extensive Air Shower Array.

The motivation for the Haverah Park project getting off the ground came largely from the British physicist Patrick Blackett, who won the Nobel prize in 1948 for his discoveries in the field of cosmic rays. The director of The Rutherford Lab (where the British atomic bomb was being developed in the 50’s), John Cockcroft (known for splitting the atom), decided there should be fundamental science going on as well as bomb building, so outside the security wire they built an air shower array to monitor cosmic rays. When this experiment was shut down, Blackett was keen to see work with shower arrays continue, and to be within reach of a university so that scientists could combine research with teaching. Blackett was working at Cavendish Laboratory with Ernest Rutherford, but moved to Birkbeck which did all the teaching in the evening so he could do research work through the day and teach in the evening. Here he met J G Wilson, also with an interest in cosmic rays, so when J G Wilson later moved to Leeds, Blackett suggested he set up an air shower array there, which was how the Haverah Park Project came about. Land was rented from local sheep farmers to install the observation huts.

Alan Watson took a lectureship job at Leeds in 1964 and began working for J G Wilson, becoming a leading member of the UK Extensive Air Shower project until its closure in the early 1990s.

We also talked about the mesmerizing power of a cloud chamber. As well as it being considered one of the most important developments for progression in the understanding of particle physics it is also emotionally and aesthetically captivating. Alan reminisced about a time at the Royal Society Summer Exhibition when a large commercial diffusion cloud chamber drew so much attention they were asked to turn it off, as mesmerised visitors blocked the entrance to the exhibition. It’s been a few years since I visited the Institute of Physics to see the large cloud chamber in the foyer, I wonder if it’s still there. I love the fact that I can build my own cloud chamber to see these cosmic visitors.

J G Wilson writing on the study of cosmic rays from his book About Cosmic Rays published in 1948, of which I have a copy:

‘It has its spectacular side, for the only laboratory which has been found big enough for its investigations is the whole of the universe to which men can win access. Most refined measurements have been made under conditions of difficulty and hazard, deep in mines and on icebound mountains, in the watses of western Greenland and cramped in the tiny gondola of a stratosphere balloon. These exploits, which are outstanding even in one of the most brilliant phases of experimental physics, are an unambiguous indication of the importance which is attached to the problems which are being studied.’

The following images from the same book show particle trails photographed in a cloud chamber -showing extensive showers and particles passing unhindered through metal plates.

J G Wilson writes about cosmic rays ‘…it is interesting to speculate on their previous history, for before it is overtaken by the catastrophe of hitting the earth, each particle is likely to have had a placid life for years, even millions of years, cruising through the wide open spaces of the universe’.

Cosmic Chiasmus: crossing the universe 2021 (video still)

The primary detectors used at Haverah Park were water Cherenkov detectors. These are large water filled tanks filled with a photomultiplier suspended in the water to capture flashes of Cherenkov light emitted by high energy cosmic rays as they pass through. The light is emitted because the cosmic rays pass through water faster than photons of light are able to, and as they do so they lose electrons thereby emitting light. The speed of light is only a constant within a vacuum, when it passes through other materials it get slowed down.

There were four 34 m2 detectors at the centre of the array in the main hut, with three detectors located 500m from the central detector. Signals from the three distant detectors were sent along buried cables to the central hut, with the signal from the central detector passing down 500 m of cable buried underground so that all signals arrived at about the same time.  When signals from the central one and two of the others arrived within ~2 x 10-6 s (called a coincidence), the signals from the photomultipliers in the 34 m2 detectors were displayed on four oscilloscope screens and photographed by one camera which had its shutter permanently open. About 20 feet of film could record around 150 events. Developed and manually scanned by Alan, or a senior colleague, the film was checked for quality and to look for any large events (ultra high energy particles arriving) which were always exciting to find. The developed film was then sent to Leeds University Physics dept for measurements.

When there was a coincidence event at the centre of the array, a signal was sent by microwave to the distant detectors set across the moorlands (on average about 2km from the central hut), the signals from these distant groups of 4 x 13.5 m2 were recorded digitally with the data going onto paper tape which was collected once each week. 

Along with the oscilloscope traces being photographed, the number on a counter was included which gave the time of each event to the nearest half minute.  In the 1960’s when this project began the time counter was advanced by a pendulum clock.  Counting time in half minutes the team found that there are roughly one million half-minutes in a year, which gave a good excuse for an annual party.

There were some brief periods in the early 1980s when a small number of scintillator detectors were also used to make cross-checks of the results from the water Cherenkov detectors against those from projects in the USA (Volcano Ranch) and Yakutsk (Siberia).  The scintillators retrieved from Imperial College’s Holborn project were brought to Haverah Park for an experiment to look at much lower energy showers.

Both types of detectors register flashes of light.  

Blackett was the first person to work out the details of Cherenkov light produced in the atmosphere. According to a memoir on Blackett, written by astronomer Bernard Lovell, who knew him very well, Blackett attempted to see Cherenkov light from cosmic ray showers with the naked eye but there is no mention of whether he succeeded. In 1962, physicist Neil Porter who built the first water Cherenkov tank in the UK at Harwell in the 50’s, did an experiment with some volunteers who were asked to recline on a coach in a dark room with a small Geiger telescope attached to a pair of darkened goggles and acknowledge if they saw a flash of light when a cosmic ray was known to pass through the googles. The observers did seem to experience a flash of light but results were ambiguous as to whether this was Cherenkov light being emitted as the particle passed though the crystalline lens or vitreous humour of the eye or a direct excitation of the retina. The experiment was a collaboration with the Psychology dept at the University of Dublin and published in Nature under the Psychology heading giving an impression that the lights were perhaps a figment of the imagination.

Aóratos 2019 video still

Astronauts are very aware of this phenomenon. During the 1970 Apollo 13 mission to the moon the power supply was damaged and the astronauts sat in the dark for several days waiting to return to Earth. They experienced flashes in their eyes and realized that some of this was Cherenkov light. Some flashes were caused by particles directly hitting the retina but Cherenkov light caused by high energy particles travelling through the matter of the eye faster than light, is much brighter. The energy is proportional to the square of the charge of the particle that comes through, so if you have an iron nucleus which has a charge 26 x the charge of a proton, you get 26 squared or 600 times as much light emitted. Out in space there are many more of these high energy particles and so the astronauts would become very familiar with these flashes, even using them to line up accelerator beams by putting their head in the particle beam to see the flashes.

An astronaut once told Alan that he was convinced that the very first people fired into space probably saw these flashes, but didn’t like to tell NASA in case it turned out to be a physiological defect of theirs and they would be taken off the space programme.

Recently, a professor friend of Alan’s who is aware of this phenomenon, has unfortunately had to begin radiation treatment for a brain tumour. He has found due to the position of the tumour and angle of treatment he can see Cherenkov light flashing in his eyes as the electrons bombard the tumour.

Aóratos 2019 cropped video still

When we met, Alan was just back from a conference in Italy discussing a paper titled ‘Ultra high energy cosmic rays: The Disappointing model’. They called it the disappointing model because they believed that the Auger results with particles at the highest energy were heavy not protons. I’m not sure I understood why it was disappointing although Alan did his best to explain: ‘It’s difficult to measure the mass of the particles of a certain energy. A deduction had been made that they have a mean mass, probably the same as nitrogen but mass changes in quite a complicated way as a function of energy. It’s to do with how deep the showers develop in the atmosphere.

Cosmic Chiasmus: crossing the universe 2021 video still

The techniques aren’t good enough to separate the particle’s mass on a one by one basis, we can only do averages. It looks like the average mass is much heavier than protons, which everybody had believed for a long, long time. Protons would be at a much lower energy. As the nucleus is travelling through space, it sees photons from the microwave background radiation and the photon will chip off a neutron or a proton, if it chips off a neutron, the neutron decays into a proton, so you can get protons this way, but they will be of lower energy. The energy reduces roughly by the mass of the particle, so an iron nucleus has a mass of 56, if you chip off a neutron or a proton that proton will have an energy, which a 56th of the energy that the nucleus has – so it goes down in energy.

Some particles could come from Centaurus A, which is a relatively close radio galaxy, it is thought that the jets from radio galaxies provide conditions to accelerate the particles, but the problem is, because the cosmic rays are charged, they get deflected in the magnetic field of the Galaxy so you can’t track them straight back to where they came from.  In terms of heavy particles that’s more of a problem because being charged means they bend even more. So one of the disappointing things is that cosmic ray astronomy is not going to be very easy. The Pierre Auger observatory has really been very successful in changing the picture quite a bit but because there are so few ultra high energy particles recorded it is slow progress. There are hopes to expand the observatory even more and also a plan to launch a satellite with detectors to pick up fluorescence light in the shower as it passes through the atmosphere, a similar phenomenon to aurora light.

Cosmic Chiasmus: crossing the universe 2021 video still

Exhibitions

The Vinyl Factory: Reverb at 180 The Strand, a multimedia exhibition exploring the intersection of art and sound with artists including Theaster Gates, Es Devlin, Julianknxx, Kahlil Joseph, Caterina Barbieri, Stan Douglas, Virgil Abloh, Cecilia Bengolea, Jeremy Deller, William Kentridge, Jenn Nkiru, Hito Steyerl, Carsten Nicolai and Gabriel Moses. Fabulous show, shame I can’t share the sounds here. Loved Jeremy Deller’s takeover of a sixth form politics class. Some of the works I had seen before but that was fine as they are worth extra viewings.

Reading

I am beginning research reading for The Geological Unconscious exhibition Julie F Hill and I are co-curating at Hypha HQ Euston opening in May 2025.

Ursula Le Guin The Winds Twelve Quarters, a collection of profound short stories each introduced by the author reflecting on the intention within.

Long after I wrote the story (The Stars Below) I came on a passage in Jung’s On the Nature of the Psyche: ‘We would do well to think of ego-consciousness as being surrounded by a multitude of little luminosities…Introspective intuitions…capture the state of the unconscious: The star-strewn heavens, stars reflected in dark water, nuggets of gold or golden sand scattered in black earth.’ And he quotes from an alchemist, ‘Seminate aurum in terrain albam foliatam’ – the precious metal strewn in the layers of white clay. Perhaps the story is not about science, or about art, but about the mind, my mind, any mind, that turns inward to itself.

Roger Caillois The Writing of Stones 1970 is a tribute to the collection of extraordinary stones Caillois acquired and which now resides in The National Museum of Natural History Paris. In these poetic chapters he describes in detail each of the stones and his fascination with the images and associations they conjure in his imagination. Questioning and celebrating the allure of the mineral and the stories hidden and revealed over millennia.

I can scarcely refrain from suspecting some ancient, diffused magnetism; a call from the centre of things; a dim, almost lost memory. or perhaps a presentiment, pointless in so puny a being, of a universal syntax.

‘A stone sky rotated above our heads’ – Italo Calvino, Cosmicomics

The culmination of two years work – A STONE SKY duo exhibition with Julie F Hill opened at Thames-side Studios GalleryReimagining the idea of an observatory – the exhibition proposes a cavernous realm of real and speculative possibilities that arise from beyond the limits of human perception. Engaging with the extended sensory range offered by technologies such as orbiting space telescopes through to the ability of birds to ‘see’ the Earth’s magnetic field, the artists’ reveal intimate connections between earth and space.

Installation shot by Ben Deakin Photography.

Susan Eyre seeks to navigate a path across time from the first human encounter with the magical qualities of the lodestone to current understanding of the interaction of the magnetic field with terrestrial life. Her works respond to the architecture, instruments and materials, found at a magnetic observatory while scientific objectives are expanded to include natural navigation techniques and extra-sensory methods used by the non-human realm, to form the basis of speculation as to the ability for humans to perceive the Earth’s magnetic field. Installation, sculpture and moving image works include a reimagined observation hut operating as a sensory hub with video screens suggesting portals into a web of neural pathways; an obelisk of layered recycled paper echoing Earth’s geological and magnetic history secreted in sedimentary strata of rock and a digital video work activated in real time by the passage of cosmic rays through a scintillator detector.

Images by Ben Deakin Photography

Julie F Hill explores the entwined darknesses of earth and cosmos. Crystalline and mineral substances from the deep earth fuse with astronomical data to suggest the deep-earth as an instrument for coming to know the cosmos. Crystalline and mineral substances formed in the continuum of deep earth and deep space allow us to peer back into cosmic time, both through the technologies created with them and the geological record they hold. Whilst darkness often indicates uncertainty and lack of knowledge, Hill asserts that it’s through darkness when we can be most perceptive to the interconnectedness between earth and cosmos. Through it we are able to extend our kinship with the inorganic and expand consciousness of what constitutes nature. Works include a large-scale sculptural print installation made from James Webb Space Telescope data that is reworked into a cavernous space, providing an experience of intimate immensity alongside more smaller sculptural and photographic works.

Images by Ben Deakin Photography

We both had ambitious large scale works to install and were grateful for the help we received from our partners (both Kevins), friends and technicians. Trevor Neale was magnificent in constructing The Absolute Hut. Anne Krinsky patiently helped apply double sided tape to the roof structure ready for the Suminagashi paper tiles and Caroline AreskogJones energetically painted the hut white and neatly edged the two way projection window. I was thrilled that, as a result of a wet few weeks, moss had started to grow on the wooden boards of the north facing wall in time for installation.

A big thank you to everyone that made it to the opening night, we were super chuffed with the positive responses.

At the private view Julie’s large scale print installation was activated by a vocal performance conjuring abyssal voices of deep, cosmic time, performed and devised with Eleanor Westbrook whose voice produces incredible hauntingly beautiful sound.

I was particularly excited to share The Breath of Stars, digital video work activated in real time by the passage of cosmic rays through a scintillator detector. After two years in development it was so exciting to watch the random starbursts appear in real time as witness to the unseen activity of cosmic rays passing through the gallery.

The kaleidoscopic video images that appear for every particle recorded by the detector, are created from footage of cosmic ray trails filmed in a cloud chamber.

The interaction of cosmic rays with atmospheric electrical fields influences the unpredictability of the magnetosphere and this random activity can be witnessed by the sudden flurries and silent gaps of the live video imagery.

These subatomic visitors from outer space power across the universe with unimaginable energy, coming from the heart of exploding stars or the depths of black holes; some may come from phenomena yet to be discovered or even from other dimensions. Travelling at close to the speed of light cosmic rays spiral along magnetic field lines, strike the edge of the Earth’s atmosphere, break apart and shower down upon us. Some particles collide and silently interact with atoms and technology on Earth. Most cosmic rays heading for Earth are deflected by the planet’s magnetic field and without this protection life on Earth could not survive this bombardment of radioactive matter. The interaction of cosmic rays and the solar wind with atmospheric electrical fields combines to influence the unpredictability of Earth’s magnetosphere, impacting the functioning of GPS satellite technology and computer processors on which humans have come to rely in daily life.

My research trip to Hartland Magnetic Observatory in North Devon was a catalyst for this body of work centring around a north facing observation hut aligned with an obelisk as a fixed azimuth mark. I am very grateful to The British Geological Survey for allowing me access to the site and particularly to Tom Martyn who shared his knowledge and gave a fascinating tour of the observatory.

The Azimuth Obelisk (of sedimentary knowledge) is a reimagining of an obelisk erected at Hartland Magnetic Observatory in the late 1950’s near the site’s northern boundary. Viewed through the window in the north wall of The Observing Building (also known as the Absolute Hut) it acts as a permanent azimuth mark from which the drift of the magnetic north pole is monitored. Currently almost hidden by undergrowth, the observatory’s concrete azimuth mark has been replaced by a digital GPS position. Much as the Earth’s geological and magnetic history is secreted into the strata of sedimentary rock, this sculpture also expresses the passage of time through the layering of recycled paper prints and drawings whose history becomes embedded within the stacked layers.

The Absolute Hut (of action potential) operates as a sensory hub with video screens suggesting portals into a web of neural pathways where a range of actions and processes are running concurrently reflecting on the dynamics between the Earth’s geologic structure and navigation using the magnetic field.

The title refers to the way neurons send information electrochemically around the body. The signals they send are called action potentials which is a temporary shift from negative to positive within the cell caused by certain ions entering the cell. Action potentials can be triggered by an interaction with the magnetic field causing a reaction in the body.

The installation is conceived from a combination of features, impressions and functions of the observing building and instruments at Hartland Magnetic Observatory in North Devon and the observation huts built in the 18th century at The Kings Observatory in Kew for meteorological and magnetic observations.

Topological contours of suminagashi marbling and plasma cut copper reflect the fluid motion of the Earth’s molten iron core and the pulsating alpha waves of the human brain when subjected to magnetic fields.

‘the internal skies have their own birds’ Italo Calvino Cosmicomics

The fascinating and perilous journeys made by migrating birds has been a natural wonder for centuries with the first records of this phenomena made more than 3,000 years ago. The innate knowledge of migratory birds is mentioned in Job and Jeremiah and the ancient Greek writers Homer, Hesiod and Aristotle noted their passage.

Job 39:26 Doth the hawk fly by thy wisdom and stretch her wings towards the south?

Wintering light two way video projection of migratory pink footed geese filmed at RSPB Snettisham on the North Norfolk coast.

Research has proven that birds and many other animals can use the earth’s magnetic field for navigation. There are two ways this happens. In birds there is a protein in the retina of the eye – (cryptochrome molecules) which trigger action potentials enabling them to visualise the magnetic field. In other animals and magnetotactic bacteria tiny crystals of magnetite respond to the field. This may also be true of humans as we do have these crystals in our brain cells.

Birds use three different compasses to navigate across the globe; the sun, the stars and the magnetic field.

Birds are also able to detect rapid movement such as individual flashes or flickering of a fluorescent light which humans see as a continuous light. Hawks which pursue other birds through dense forests at high speeds, follow the movement of their prey while avoiding branches and other obstacles. To humans travelling at this speed, the fleeing prey, branches and obstacles would just be a blur.

Degrees of Variation considers what it might be like to have the sensory powers of a bird where a protein in the eye is excited by polarised light making it possible to see the magnetic field and follow a visual navigatory cue in an accelerated world. The video imagines flight over water and through woods while being guided by the force of a magnetic field.

Calvino’s story The Stone Sky is wonderfully descriptive of the volatile geological structure of the Earth. This fluidity is what makes life on Earth possible. Only planets with fluid cores have magnetic fields. The geological interior generates a field that reaches into outer space offering a protective shield.

internal skies : external spheres video sequences within concentric circles mimic the geological structure of the Earth to explore the relationship between Earth’s magnetic field and various methods of navigation including via magnetoreception and celestial observation. Sequences include star trails around Polaris (the current north star), birds and bees that use the magnetic field for navigation, magnetotactic bacteria, magnetised iron filings, aerial views of the coastline around Hartland and early morning polarised light which excites the cryptochrome protein in a birds eye.

The Earth’s geomagnetic field is created by a combination of three separate fields and timescales. The main field is generated in the earth’s molten iron core.  Observing the field gives clues to the planet’s deep interior which is inaccessible to direct observations. Changes are measured in the annual drifting of magnetic poles. Secondly electrical currents caused by solar weather and cosmic rays bouncing off the Earth’s main  field charge the surrounding ionosphere causing fluctuations in the field. This field changes by the micro second as we orbit the sun. The Earth’s magnetic field also acts as a shield against most potentially harmful charged particles from outer space. Finally the residual magnetisation of the geology of the rocky mantle and crust, measured in deep geological time also offers clues to the geological history of Earth.

The understanding of the world surrounding us forms in the darkness of our skulls. 

interference – a panel of 12 small video screens inside The Absolute Hut (of action potential), showing images of the human brain filmed by using polarizing filters to create pulsating birefringence colours, relate to the narrative pinned to the outside of the hut.

The narrative is a mix of fact and fiction based on a real experiment carried out at Caltech where scientists found Alpha waves in the human brain do respond to Earth’s magnetic field and other research suggesting that it could be possible for the magnetic field in one animal’s brain to transmit information to another animal’s brain by triggering action potentials creating the same thoughts and emotions.

Instruments of the Anemoi are a set of dodecagon tablets cast in Snowcrete, a non-magnetic cement, as used in a magnetic observatory. Suggestive of the pedestals that support various instruments used in monitoring the Earths’ magnetic field they also respond to an ancient anemoscope “table of the winds” carved in marble around eighteen hundred years ago and inscribed with the Greek and Latin names of classical winds on each of its twelve sides. Envisaged here as speculative objects, instruments and schematics wrought by the wind gods, the first emissaries of navigation and orientation.

One tablet holds a copper bowl with a ‘silver fish’ floating in water. The shape of the ‘silver fish’ is based on the oval shaped compass needle (illustrated in Breve Compendio de la Sphera de la arte Navegar by Martin Cortes 1551)  and refers back to wafer thin fish shaped iron leaves used by 11th century Chinese geomancers.

Nails and iron filings on the second tablet reveal an embedded magnetic field recalling a legend that the discovery of the lodestone was made by a Greek shepherd who noticed the nails in his boots were attracted to the rock (magnetite) beneath his feet.

The third tablet is embedded with copper etched with images and names based on associations and attributes of the twelve Greek wind gods set in a traditional compass rose.

Domain of the Devil Valley Master uses industrial directional magnetic steel, sanded and etched to reveal the Goss texture of rolled iron silicon alloy crystals. The jigsaw pattern of magnetic domains give this material exceptional magnetic properties. The simple evocation of a spiral described in geologically informed polygons draws upon many references, from the shape of our own Milky Way Galaxy sculpted by vast cosmological magnetic fields and the spiralling molten dynamo generating Earth’s magnetic field, to the inner pathway of spiritual growth and the route to the symbolic omphalos (navel) at the centre of the world where the sky entrance and the underworld meet. The title of this work originates from an ancient Chinese manual on the skills of persuasion, The Book of the Devil Valley Master, containing the first known mention of a compass, known at the time as a south-pointer.

The exhibition closed with an afternoon event launching our publication which includes the essay Dark Nights and Signs of Unseen Things by Anjana Janardhan. There was also a live cloud chamber demonstration of mesmerising cosmic ray trails, artist tours and informal readings.

Publication available – DM via blog comments box for more details or visit Julie’s shop

Really pleased with the results I am getting from the new batch of directional magnetic steel sent from Union Steel Products. These are coming out better than in previous tests.

Norman P. Goss invented grain-orientated steel in 1934. It was produced through a two-stage cold rolling process with intermediate annealing between the cold rolling stages. Grain-oriented electrical steel enabled the development of highly efficient electrical machines, especially transformers. Today, the magnetic cores of all high-voltage high-power transformers are made of grain-oriented electrical steel. The strong preferred crystallographic orientation is known as a Goss texture.

When I receive the electrical steel it has a grey insulation coating which has been applied to both sides of the sheet to avoid eddy currents between the stacked sheets when used in a transformer core. I am removing this coating by sanding. I then etch the sheets in copper sulphate solution for 20 minutes. The plate must be dried very quickly when it is taken out of the etching bath. I then lightly polish and wax the surface. Some detail is lost quite quickly and areas can become muddy after etching so I still need to experiment a little more with alternative cleaning and sealing methods.

A previous batch had a different coating that proved impossible to remove cleanly even with the most extreme methods. This new batch has two different types of sheet which have a slightly different pattern to reveal. It is quite hard work but a fascinating material to experiment with.

I have been considering using the Directional Magnetic Steel Pieces in some form of suspended sculpture as movement causes the surface to catch the light revealing the patterned surface of this material. I might use it to mark the line of declination across the gallery floor from True North to Magnetic North at the time of installation.

Thinking about moving sculptures –

Imagine holding Einstein’s attention for the forty minutes it takes your work to revolve. A Universe by Alexander Calder 1934, painted iron pipe, steel wire, motor, and wood with string. One of the first artists to explore kinetic and motor driven sculpture, expanding drawing into 3D and painting into motion. A nice intro to Calder from 2016 – The Universe of Alexander Calder with Dara Ó Briain.

Work continues on the Azimuth Obelisk with the construction of the metal frame to support the structure and hold the layered paper sheets. Thanks to Giles Corby of the London Sculpture Workshop for getting to grips with my diagrams and welding the frame. The frame is made in three interlocking parts to distribute the weight and make for easier storage and transportation. This sculpture is a response to the concrete obelisk erected in 1955 at Hartland Magnetic Observatory, near the site’s northern boundary as a permanent azimuth mark. It is viewed via a theodolite through a window in the north wall of the Absolute Hut, its azimuth being 11º27’54” E of N and marks the point from which the magnetic north pole is tracked as it drifts westwards.

The British Bryological Society celebrates its centenary this year, promoting the study of mosses and liverworts. I have been searching their website for clues on growing moss. Most of the information is on the identification of mosses but I did find a useful downloadable pdf of The Moss Growers Handbook by Michael Fletcher. No mention of liquidising moss with yoghurt as a starter culture though.

Gathering moss, liquidising with yoghurt and painting on to reclaimed old boards.

I made a rough model of The Absolute Hut to work out how many boards I will need for the north facing wall to try and grow moss on. I like that it turned out looking like a bird house as inside will be video exploring the magnetoreception of birds. This work is a reimagining of the Absolute Hut at Hartland Magnetic Observatory where monitoring of the Earth’s magnetic field takes place.

Some speculation on human magnetoreception:

Neurons send information electrochemically around the body. The signals they send are called action potentials which is a temporary shift from negative to positive within the cell caused by certain ions entering the cell. Research has proven that some animals can sense the magnetic field via cryptochrome molecules in the retina which trigger action potentials. New studies have been carried out looking at iron particles (Fe3O4) found in the brain using supersensitive magnetic sensors to read the brain’s magnetic field. Receptor cells containing crystals of magnetite could register changes in magnetic fields and report this information to the brain.  

One study suggests that it could be possible for the magnetic field in one animal’s brain to transmit information to another animal’s brain by triggering action potentials creating the same thoughts and emotions. There have been experiments with rats and fruit bats which claim brain to brain communication has occurred. Alpha waves in the human brain have been shown to respond to magnetic fields. Alpha waves are always present, but are more prominent when at rest. The experiment, carried out at Caltech, mimicked how a person might experience the Earth’s magnetic field when turning their head. 

Maybe putting our heads together can exchange thoughts telepathically.

I have taken the contour lines from a publicly available World Magnetic Model Field Map as a framework for layering in the video work on bird magnetoreception.

An early frosty morning captured the sun melting the ice on the lens of the spy cam in the garden.

I have built the protective box frame for the monitor that will be inside the mollusc/rock sculpture Belly of a Rock. Thanks to Pete next door for cutting the wood for me. I plan to build the shape up with mesh covered in paper clay. I have had the idea to make small circular paper clay clumps with swirls of crushed shell on each one and build the form up from these. I have been given a lot of oyster shells and have collected mussel shells which I have tested crushing with a pestle and mortar.

The drift of the magnetic North pole was first recorded in 1831 and historically would wander between 0–15 km a year but since the 1990’s it has sped up to drift 50–60 km a year. Tracking changes in the magnetic field can tell researchers how the iron in Earth’s core moves.

Earth’s magnetic field is created in the swirling outer core. Magnetism in the outer core is about fifty times stronger than it is on the rocky surface of the Earth. At the centre of the Earth is the inner core which is divided into eastern and western hemispheres. In the inner core, the temperature is so high, materials lose their permanent magnetic properties as the atoms are so thermally excited they can no longer align to a magnetic point. This is known as the Curie temperature.

The hemispheres of the inner core have distinct crystalline structures and the western hemisphere seems to be crystallizing rapidly whereas the eastern hemisphere may actually be melting.  Geoscientists have also recently discovered that the inner core has an inner core. A radical geologic change about 500 million years ago may have caused this inner inner core to develop. Here the crystals are oriented east-west instead of north-south and are not aligned with either Earth’s rotational axis or magnetic field. The inner inner core crystals may have a completely different structure to the hexagonal close-packed (HCP) phase of iron that is stable only at extremely high pressure and so may exist at a different phase.

ESA’s three-satellite Swarm mission was launched in 2013 to monitor Earth’s magnetic field by measuring magnetic signals from Earth’s core, the crust, oceans, ionosphere and magnetosphere. Using data from the Swarm mission, scientists have discovered energy generated by electrically-charged particles in the solar wind, which can be disruptive to communication systems, flows asymmetrically into Earth’s atmosphere towards the magnetic north pole more than towards the magnetic south pole. They have also discovered a completely new type of magnetic wave that sweeps across the outermost part of Earth’s outer core every seven years. These magnetic waves are likely to be triggered by disturbances deep within the Earth’s fluid core. Research suggests that other such waves are likely to exist, probably with longer periods.

Geomagnetic jerks are sudden powerful waves that occur about every three to 12 years and are not consistent across the globe. It seems these jerks originate from rising blobs of molten matter that form in the planet’s core up to twenty five years before the related jerk takes place. The current findings from Swarm are part of a long-term project to predict the evolution of the geomagnetic field over the coming decades.

Polarised light is when the waves of electric and magnetic fields vibrate preferentially in certain directions. This can happen when light bounces off a reflective surface like a mirror or the sea. It can also happen in space as starlight travels through gas and dust clouds. Polarisation carries a wealth of information about what happened along a light ray’s path and astronomers can study the physical processes that caused the polarisation.

The Milky Way is filled with a mixture of gas and dust from which stars are born. Cosmic dust grains are almost always spinning rapidly, tens of millions of times per second, due to collisions with photons and rapidly moving atoms. The spinning dust grains become aligned to the direction of the magnetic field. They emit light at very long wavelengths from the infrared to the microwave domain which comes out vibrating parallel to the longest axis of the grain, making the light polarised.

Visualisation of data from ESA’s Planck satellite shows the interaction between interstellar dust in the Milky Way and the structure of our Galaxy’s magnetic field. Polarisation-sensitive detectors were able to capture the data as interstellar dust grains tend to align their longest axis at right angles to the direction of the magnetic field resulting in light emitted by clouds of gas and dust being partly ‘polarised’. Researchers are using the polarised light from interstellar dust to reconstruct the Galaxy’s magnetic field and study its role in galaxy evolution and star formation. From this data it can be seen that across the galactic plane there is a strong regular pattern but in some areas there are tangled features where the local magnetic field is particularly disorganised.

New images from NASA’s James Webb Space Telescope show star formation, gas, and dust in nearby galaxies with unprecedented resolution at infrared wavelengths. NGC 1433 is a barred spiral galaxy with a particularly bright core surrounded by double star forming rings. For the first time, in Webb’s infrared images, scientists can see cavernous bubbles of gas where forming stars have released energy into their surrounding environment.

The Observable Universe 2018 by Pablo Carlos Budasi. The furthest we can see is the faint glow from the cosmic microwave background emitted 13.8 billion years ago.

From Earth we become the centre of the eye that gazes out but we have no idea of the full size of the universe or if we are embedded in a multiverse.

The unobservable universe makes up the vast majority, around 95% of the universe. Zero, a symbol to mark nothing, sits on the boundary between absence and presence indicating what might have been or might come to be. Where we thought there was nothing we have found so much.

Gallery Visits

Preconscious Landscape at Exposed Arts Projects – an interesting space for arts based research projects. Artists: Lynne Abrahamson, Gabriele Beveridge, Matilde Cerruti Quara, Konstantinos Giotis, Sotiris Gonis, Ramona Güntert, Raksha Patel, Hamish Pearch, Anna Perach, Chantal Powell, Candida Powell-Williams, Paloma Proudfoot, Aziza Shadenova, Holly Stevenson, Maro Theodorou, Adia Wahid & Meng Zhou all grapple with an unresolvable psychoanalytic question: what does it mean for the conscious mind to try to understand its own preconsciousness?

Richard Mosse Broken Spectre at 180 The Strand. Seventy minutes of emotionally uncomfortable yet beautifully riveting viewing. Endless overwhelming destruction. Burnt forest. Subterranean fires. Intensive cattle farming. Aggressive gold mining. Wide wide screen images that slip between dreamlike garish colour and chilling monochrome with a soundtrack that sounds like the forest itself crying. The brutal disrespect for the land, the non-human and the people of the Amazon rainforest captured in heartbreaking detail as it slips through our fingers. Having been looking at moss recently the large photographic works at the entrance to the film come across very moss like and emphasises the micro and macro nature of the world.

Cable Depot presents Insert Coin, a project by Bob Bicknell-Knight exploring predatory monetisation practices within video games, specifically loot boxes, and the ongoing insertion of gambling mechanics into virtual experiences. Tapping into our desires and the addictive thrill of winning Bob Bicknell-Knight invites us across the digital divide into a luminous world of pixels and 3D printing. I was delighted to win an island. Here everything is free so there is no uncertainty and debt to mar the experience.

As our physical lives are becoming increasingly gamified the game industry has, for almost twenty years, been inserting ways of gambling real world money into video games. From purchasing extra lives to play another level in Candy Crush to buying new cosmetic options for your guns in Call of Duty, spending money within video games has become increasingly prevalent.

One of the most prevalent and destructive forms of monetization are loot boxes, consumable virtual items that are bought within video games which can be redeemed to receive a randomised selection of further virtual items, ranging from simple customization options for a player’s avatar or character to game-changing equipment such as weapons and armour. As the items are randomised players have previously spent thousands of pounds attempting to gain specific products in different games. As these gambling mechanics have become more prevalent, with considerable harm being done to young people and players with gambling addictions, loot boxes are now illegal in several countries, whereas recently the UK government decided that loot boxes will not be regulated under betting laws.

Champs Noir curated by Simon Leahy-Clark at Terrace Gallery. A carefully chosen collection of works in black from a great catalogue of artists. Featuring: Michael Ashcroft, Bensley and Dipre, Diane Bielik, Andy Black, Cedric Christie, Gemma Cosse, Graham Crowley, A Ee, Nicky Hodge, Mandy Hudson, Michael Kaul, Sarah Ken, Sharon Leahy-Clark, Simon Leahy-Clark, Graham Lister, Brendan Lyons, Alistair MacKillop, Mutalib Man, Enzo Marr, Donna Mclean, Neil Metzner, Jane Millar, Josh Mitchell, Jost Munster, Stephen Palmer, Kasper Pincis, Andrew Seto, Peter Suchi, Sally Taylor, Chris Tosic, Mark Wainwright & Tom Wilmott. Selected image: Jane Millar: Test Bed, ceramic media, 12cm diameter, 2019.

Julie F Hill Earth, Water, Night at The Stone Space

We so often look out at the night sky forgetting it is gazing back at us.

‘… The [pool] is the very eye of the landscape, the reflection in water the first view that the universe has of itself …’ —Gaston Bachelard,

Holding the poetic and alchemical in contrast to the objective and scientific, astronomical data of deep space folds into Earth’s deep time. Light and shadow gather in pools of water, forming images that suggest consciousness is a fundamental property of all matter.

Beautiful and contemplative works capturing the milkyness of the Milky Way caught in the folds of the night sky; distorted reflections rippling across dark pools; illusory depths oscillating between dimensions.

Sam Williams Deep in The Eye and The Belly (Part One) at San Mei Gallery. It was a busy night at the opening and I didn’t take any photos. There was a large projection on one wall and two other films showing on monitors with headphones. The work describes stories of cetacean bodies, interlacing actual historical events with speculative narratives. The camp narration of the main film deliberately jars with the emotive subject matter, but is given context through the supporting films as the protagonist who features across each film is seen reclining wearing feathers and glittery regalia speaking in long drawn and world weary sentences or lamenting the loss of the whale in absurd song from the vantage of a lighthouse.

Reverse Parking at Thames-side Gallery curated by Peter Lamb and Katie Pratt.

Reverse Parking presents seven artists (Gordon Cheung, Will Cruickshank, Cristallina Fischetti, Oona Grimes, Paul Hosking, Peter Lamb and Katie Pratt) whose work explores the duality of reality and the technological sublime. A bold and vibrant show. Good to see some large work from Oona Grimes and to chat with her in the gallery; her battle scenes encompassing battles down the ages coincidentally emerged at the onset of war in Ukraine. Also interesting to hear Katy Pratt discuss her language of abstract painting on the excellent Art Fictions podcast.

…not necessarily in the right order at Stephen Lawrence Gallery takes a playful cue from the Morecambe and Wise sketch with special guest Andre Previn which is embedded in British cultural history. Work from the featured artists (Carol Wyss, Dominic Murcott, Graeme Miller, Dirty Electronics and Dushume) overlaps and layers through still image, sound and projection. Exhibited is the third iteration of Carol Wyss’s giant etchings that expose the inner recesses of the human skull. Here they are made luminous and their sculpted landscapes all the more surreal by the animated light sequences traversing their surfaces.

Reading

Not observant enough to realise I bought the pocket guide version of The Natural Navigator by Tristan Gooley I ended up with an unembellished rather prosaic read with lots of facts and charts and possibly useful information that requires a large investment of dedication to the cause to learn many of these techniques. What was amusing though was finding the section headed Mosses and Lichens opens with the paragraph –

‘There is a commonly held belief that “Moss grows on the north side of trees and buildings.” It does, sometimes, but will also grow on every other side.

He goes on to say that moss doesn’t care about direction, but it does care about moisture. So in the northern hemisphere the side away from the sun is preferred by moss as it retains moisture for longer. Gradient is also important to prevent run off of water. I have tried to prop my planks at as low an angle as possible in the side passage but may need to find somewhere I can lie them down more.

I am enjoying dipping in to Florian Freistetter’s A History of the Universe in 100 Stars. No longer a swathe of uniform twinkling points of light but each star has its own character and story. It starts with 100 stories but we can extrapolate that to consider each of the many billion stars as individuals.

Listening

In Our Time – Superconductivity Excellent guest speakers (Nigel Hussey, Professor of Experimental Condensed Matter Physics at the University of Bristol; Suchitra Sebastian, Professor of Physics at the Cavendish Laboratory at the University of Cambridge; Stephen Blundell, Professor of Physics at the University of Oxford) on this podcast. Superconductivity was a surprising discovery in 1911 by the Dutch physicist Heike Kamerlingh Onnes who found that when he lowered the temperature of mercury close to absolute zero and ran an electrical current through it, there was no resistance to the current. Many other materials have also been found to share this property when cooled to a pivotal temperature when the material suddenly enters a different phase and behaves in a completely different way. As water moves from solid to liquid to gas at different temperatures so metals can move between solid, liquid and superconductor. Further research found that a superconductor also expels magnetic fields and this has been exploited in the making of MRI scanners and to speed particles through the Large Hadron Collider.

I also enjoyed hearing how, what were once impossible numbers, called imaginary numbers by Descartes, have turned out to be fundamental and integral to explaining oscillations and the sort of wave like structures in the universe that we encounter when diving into a quantum world.

The Curious cases of Rutherford and Fry – The impossible number