Lyme Regis Fossil Walk

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The weather on the Wednesday of our holiday was awful – warm, bright, sunny and calm. Awful for fossil hunting anyway. The best time is after rain or heavy seas when they are washed out of the mud and clay. That’s what Paddy Howe and his colleagues leading the fossil walk booked via Lyme Regis Museum told us.

Lyme Regis  is flanked by cliffs of shale, clay and mudstones with some limestone which are full of fossils from the Jurassic period. As the cliffs crumble and large sections of them fall down onto the beach as landslips, fossils of creatures that died when Britain was part of a massive land mass and located nearer to the equator many millions of years ago start to be revealed. There have been some important finds on these beaches in the past. Including the first complete Ichthyosaur, a complete skeleton of the long-necked Plesiosaurus and a Pterodactylus  found by Mary Anning (1799–1847)

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So, a guided fossil walk is a must during a stay in Lyme. They’re great fun  and educational too and suitable for adults and children – who doesn’t enjoy poking around on the beach? There are several providers including the Museum, and they’re very popular. We’d originally wanted to go on one on the Monday, but when we went to the Museum on Sunday morning we found the earliest one with enough places available for 4 of us was Wednesday.

They go out rain or shine the start time depending on the tide. Ours started at the civilised hour of 10:30 a.m., meeting in front of the museum. Paddy Howe, the Museum’s geologist and something of a minor celebrity (I’ve seen him on TV a few times and he helped out Tracey Chevalier when she was researching her book Remarkable Creatures) gave a short introductory talk and we set off towards the beach. We stopped at the end of the new east sea wall and Paddy ran through the reasons for the fossils being abundant in Lyme and showed us examples of different types of fossils we might find so we knew what to look for. These included the ubiquitous ammonites, belemnites, “devil’s toenails” (a type of mollusc), other bivalves, sea urchins, fossilised fish, crinoids and coprolites (fossilised faeces!). If we were lucky we might find bones from ichthyosaurs and other prehistoric  creatures! We were promised that despite the poor fossiling conditions we would find something.

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This is Paddy (he’s acquired a beard since our previous visit)

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and here’s Paul. one of the other guides

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The guides were all helpful – examining possible specimens and cracking open stones that looked like they may contain fossils. At the end of the tour Paddy cracked open a number of limestone nodules, distributing to children the fossils they contained.

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As promised, we didn’t go away empty handed. This was our fossil haul.

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Nothing spectacular, but a few small ammonites embedded in limestone, some mudstone with impressions of ammonites, some pieces of belemnite and a shard of a fossilised oyster shell.

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About Time!

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During our recent short break in London, we checked in our hotel around midday on the Saturday , left our bags and headed down to the pier by the Tower of London where we caught a boat which took us along the Thames to Greenwich. Our main objective was the Royal Observatory, on top of the hill in Greenwich Park.

It seemed that for most visitors the main reason for paying the entrance fee was so they could have their photograph taken while standing astride the Prime Meridian and were quite happy to queue up for 40 minutes or so to do this. I couldn’t see the attraction myself. After all the meridian goes right round the globe and there are plenty of places where you can stand with the right leg on one side and the left leg on the other.

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As for us, we were more interested in looking round the original Observatory building – Flamsteed House which was designed by Sir Christopher Wren in 1675 -  and the Time Galleries exhibition.

Flamsteed House is quite small and as it was a working building has been altered many times over the years. The most interesting, and best preserved, part was the Octagon Room, which seems to very much as designed by Wren.

Unfortunately it was difficult to take photographs due to the number of people milling around

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According to the Museum website, the Octagon Room

was designed to observe celestial events including eclipses, comets and planetary movements. However, the positioning of Flamsteed House meant that the original purpose of the Observatory could not be fulfilled from the Octagon Room. With big windows, the room was perfect for watching the sky, but not ideal for positional observations, because none of the walls were aligned with a meridian. Most important positional observations were actually made in a small ‘shed’ in the Observatory gardens

Another case of “men in sheds”!

The Time Galleries contain an exhibition about the need for accurate timekeeping and the role it plays in our everyday lives. The highlight were the three timepieces made by John Harrison.

Quite a few years ago I read “Longitude” by Dava Sobel. A best seller, it told the story of how Harrison, set out to solve the problem of how to determine longitude when out at sea. Failure to do this accurately had cost many lives and in 1714, the British Government offered a prize of £20,000 for a solution which could provide longitude to within half-a-degree. That’s a lot of money now and an absolute fortune at the beginning of the 18th Century.

John Harrison, an ordinary carpenter from Lincolnshire with little formal education and an interest in clockmaking set out to solve the problem by constructing an accurate timepiece. Not so easy when iit would be located on a ship out at sea tossed by stormy seas and in an aggressive salt laden atmosphere. Sobel’s book tells the story of how, after several attempts, he finally succeeded in constructing a practical, accurate timepiece, the first marine chronometer. Being an ordinary bloke, the Establishment made things difficult for him, but finally, grudgingly, the “Board of Longitude” awarded him the prize.

The Observatory has all of Harrison’s original prototypes on display.

This is “H1”, his first attempt. The moving parts are controlled and counterbalanced by springs so that, unlike a pendulum clock, they work independent of orientation.

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Amazingly precise for it’s time, but Harrison knew it could be improved. He managed to get some money from the Board of Longitude to refine the design which resulted in H2

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However, he realised the design was flawed as the bar balances did not always counter the motion of a ship. So he convinced the Board to let him have some more money and came up with H3.

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It incorporated two developments – a bimetallic strip, to compensate the balance spring for the effects of changes in temperature and a caged roller bearing. However, it didn’t probe accurate enough in tests. He realised he’d reached a bit of a dead end with this approach and so went back to the drawing board.

He finally came up with H4, a completely different design. Essentially a large pocket watch, 13 cm in diameter and weighing 1.45 kg. A much more practical design for taking to sea and it worked.

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The story isn’t over yet. It took another 9 years before Harrison got his prize. the whole venture had taken 43 years from start to finish.

There’s a good summary of the saga on the Museum’s website, here.

Schrodinger in Dublin

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I think that most people these days has heard of “Schrödinger’s cat”, even if they don’t really know what that’s about. Essentially it was a “thought experiment” devised by the Austrian physicist Erwin Schrödinger  try to illustrate a contradiction in the theory of quantum mechanics.  I mainly associate him with his wave equation which I struggled to get to grips with when I was studying chemistry at University many many years ago.

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Until my recent visit to Ireland I never realised that Schrödinger had lived there, but he emigrated to Ireland in October 1939 to work at the newly established School of Theoretical Physics at the Dublin Institute for Advanced Studies.  For many years the School was based at this house on Merrion Square South.

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An outspoken critic of the Nazis, he was suddenly fired from his University job in Austria for “political unreliability” and had to flee the country.

Schrödinger lived and worked in Ireland for 17 years, becoming a naturalized Irish citizen in 1948, (but retained his Austrian citizenship), before returning to Austria. While he was there he continued to work on the philosophy of quantum theory and also became active in the emerging field of molecular biology.

What the Higgs …?

Event display showing particle tracks from a collision as seen by the CMS experiment

Image source:CERN

The (probable) confirmation of the existence of the “Higgs boson” at CERN (Conseil Européen pour la Recherche Nucléaire  i.e. European Council for Nuclear Research) near Geneva, has been all over the news this week. But I reckon most people don’t really know what it is.  Here’s a couple of attempts to explain it in layman’s terms,

one from Jonathon Amos at the BBC using ping pong balls and sugar

another from Don Lincoln, a nuclear physicist from Fermilab in the USA

a slightly more technical explanation by one of the boffins at CERN, with equations written on his tee shirt,

And for some alternative approaches to explaining what it is, see here.

As someone who studied chemistry, my view of particle physics is that it is seriously weird. Things are both particles and not particles, they can be in two places at the same time and it’s impossible to know both where they are and how fast they are moving. Everything is about probabilities, so the uncertainty about whether CERN have actually discovered the darn thing or not is par for the course!

Jeremiah Horrocks and the transit of Venus

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Anyone getting up early at the crack of dawn this morning in Lancashire to observe the transit of Venus would have been disappointed. The sky was covered by a blanket of white cloud that obscured the sun. Luckily this wasn’t the case at 3:00 pm on 4 December 1639 (24 November  according to the Julian calendar that was then in use) as it was on this date that Jeremiah Horrocks observed this rare astronomical event from the garden of a house in Much Hoole, a village just south of Preston.

Jeremiah Horrocks, was probably born in Toxteth, then a hamlet just outside Liverpool, but today part of the inner city, in 1619. He was obviously a bright lad as at only thirteen he entered Emmanuel College, Cambridge as a “sizar” ( a poor scholar). In those days Universities were establishments for training men for the clergy, but while he was there Horrocks studied astronomy. Apparently he was the only person at Cambridge at that time to accept Copernicus’  heliocentric theory – i.e. that the the planets, including the Earth, orbit the sun.

In 1635 he returned to Toxteth and using Kepler’s Laws of Planetary Motion, worked out that the Moon had an eliptical orbit.

The transit of Venus is where the planet passes between the Earth and the sun, and (if you’re lucky!) can be seen as a dark dot passing across the face of the sun. Pairs of transits occur eight years apart separated by long gaps of 121.5 years and 105.5 years. It was Horrocks who worked out that they occurred in pairs.

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Animation of simulated transit in equatorial coordinates. Picture source: Wikipedia

Unfortunately, Horrocks died on January 3rd 1641 at the early age of 22. I wonder what he would have achieved if he’d lived longer.

There’s a memorial plaque to Horrocks in Westminster Abbey and two stained glass windows in St.Michael’s Church, Much Hoole. And recently a memorial was erected at the Pier Head in Liverpool. This monument, by Andy Plant, is in the form of a telescope pointing to the Sun and Venus. I snapped it during a recent visit to Liverpool. The photo isn’t that great – I took it with the camera on my mobile phone and it was a grey, overcast day. There’s a better picture on the artist’s website

According to Andy Plant’s website:

The sculpture has a working hand powered mechanical orrery, the position of Venus has been replaced by a copper angel version of Jeremiah and as his wings flap he orbits the other planets. Inside the large telescope there is a video animation of the life of Jeremiah by Tim Hunkin.

Horrocks was also a poet and there’s an extract from one of his poems, describing the long wait until people would be able to see the next transit of Venus, inscribed on the base of the sculpture.

Thy return posterity shall witness;

Years must roll away,

But then at length the splendid sight

Again shall greet our distant children’s eyes

Unfortunately the cloud shielded this splendid sight from our eyes this morning!

Beautiful Minds – Jocelyn Bell Burnell

The Vela Pulsar

On Wednesday this week I watched the first of a series of 3 programmes profiling British Scientists. It told the story of Jocelyn Bell Burnell, who, as a postgraduate student, discovered pulsars – highly magnetized, rotating neutron stars that emit pulses of radiation at regular intervals.

Jocelyn Bell comes across as a genuine, self efacing, modest person. She speaks quietly with a distinct brogue revealing her Northen Irish origin (interestingly, her sister, who was interviewed during the programme, didn’t have a trace of a Ulster accent!). The programme included segments of an interview with her, where she expressed views on the practice of science but mainly concentrated on the story of her discovery of pulsars. As a PhD student in Cambridge, working under Antony Hewish, she was given the task of building a radio telescope (not the dish type but a field full of wires) and analysing the data obtained. Being in the 1950’s this data was in the form of chart recorder data – yards and yards of paper.During this analysis she noticed a series of small “blips”. Initially dismissed as “noise” by her superiors she carried on obtaining better data by slowing down the pen recorder! This allowed her to analyse these “blips” in more detail and it was then quite clear that she had found a series of regular pulses,  This led to quite a furore as initially it was thought these could be signals from ET. However, she went on to analyse other parts of the sky where she found similar signals, ruling out the ET theory.

Despite this marvellous work, it was her supervisor, Antony Hewish, who was awarded the Nobel prize. JBB didn’t get a mention. Hewish was interviewed during the programme and justified this by almost dismissing JBB’s role and arguing that it is a team effort and that the team leader is the person who deserves any credit. I think this was absolutely disgraceful and is indicative of the attitude of the scientific establishment. The “top men” taking all the credit and glory and also the embedded misogyny. Despite this, when discussing it during the programme (and I’ve seen other interviews with her where she takes the same attitude), she does not come across as bitter. I don’t know whether she feels any anger inside – if so, she does a good job of hiding it. I suspect this is partly explained by her religion – she is a Quaker and a gentle, stoic attitude and lack of bitterness seems to go allong with that.

Although I enjoyed the programme the content was inevitably limited it mainly concentrated on the pulsar story, only touching on other aspects of her life and career. I would have liked to have known more about how she squares her deep religious conviction with being a scientist and to have learnt more about her career after the 1950’s.  In other programmes I’ve seen about her life she has mentioned how difficult it was to work in science as a mother with young children and how she was able to keep in touch by working as a tutor for the Open University.

More information on JBB can be found on the Internet including some interviews with her that delve into some more detail, here.

Picture credit: NASA via Wikipdedia http://heasarc.gsfc.nasa.gov/docs/objects/heapow/archive/compact_objects/vela_pulsar_jet.html