Today marks the 20th Anniversary of the formation of the Society for the History of Astronomy on 29th June 2002.
One of the core activities of the Society is to collect details of lesser-known figures in astronomy and their related organisations, buildings/structures/sites, known as ‘The Survey’. The information gathered can be found on the website constructed for this purpose. https://shasurvey.wordpress.com/
A celebration Book has been written to commemorate the anniversary.
Details of how to purchase a copy of this book can be obtain from the chair, Gerard Gilligan, at firstname.lastname@example.org
at The Birmingham & Midland Institute, 9 Margaret St, Birmingham, B3 3BS.
Speakers Emily Winterburn : Tracking down the lost & forgotten astronomical women of Empire Daniel Belteki : James Glaisher and the Editor-ship of Illustrated London Almanack Lee Macdonald : Proposals to move Greenwich Observatory Hilary Forbes : Aristarchus Allan Chapman : From Hershel’s 48inch to the JWST in 200 years. Where next?
The Society will suspend all meetings and BMI Library openings until further notice. This is due to the current situation and the need for containment of the C-19 virus outbreak. We will keep members informed and council officers will be in contact with those members, in the next few days, who have paid for meetings attendance and associated refreshments already. Venues, Invited speakers and visitors are being contacted separately by members of council.
While we realise that the cancellation and postponement of events and meetings will cause some inconvenience and disappointment, the health and wellbeing of our society members, venue staff and visitors is our highest priority.
We hope to re-arrange some events/meetings later in the year.
I wish you good health at this time, and please follow the official advice:
The Society for the History of Astronomy AGM and Moon themed conference was held on a wet and windy day the 26th October 2019 at the Birmingham Midland Institute in Birmingham. We wish to thank all the attendees and speakers for who had to battle through less than ideal travel conditions to reach the conference.
Gerard Gilligan opened the conference with the
AGM with a touching speech about Stuart Williams who had sadly passed away on
the 15th October. Stuart had been a cornerstone of the early society
and had been very influential in getting the society started. He will be
greatly missed by many of the members.
The AGM passed, all returning officers were reinstated and Gerard gave his thanks for another successful year, particularly highlighting the Oxford conference which had been a highlight for many of the members. Prizes were awarded as follows: The Peter Hingley award was presented to Carolyn Bedwell for all her hard work with the library and The Roger Jones award for survey contributions went to Bill Barton for his continued submissions to the survey. The next AGM will be held at the BMI Birmingham on the 24th October 2020.
Mike Frost, the BAA Historical Section Director, told the members that they have a new orbituary section of BAA members that is now on the BAA website which can be found here https://britastro.org/node/16732 I am sure many of our members will find this an excellent resource. The venue for the BAA 2020 Historical Section meeting will to be confirmed soon but is likely be at the BMI in Birmingham. The final news from Mike is that Lee McDonald is stepping down as deputy director and Bill Barton is assuming the role.
During a short interlude, Eddie Carpenter showed the delegates several lunar themed items he had brought with him. Firstly there was ‘The First Moon Atlas’ by William Henry Pickering which can be viewed online here https://archive.org/details/moonsummaryofexi00pickuoft. This book was published in 1902 and all the images included were taken in the late 1800’s. The second book was ‘The Moon’ by Richard A. Proctor. Eddie’s edition was very special as his was one of the first ten printed, which included three real and not printed photographs of the Moon taken by Rutherford in 1856. Eddie finally brought some lantern slides of the Moon plus some glass plates of the moon and some stereographic images and stereo glasses with which to view them. These interesting contributions can be seen in the image below right.
Our first speaker was Heather Sebire, an archaeologist and the Senior Property Curator at Stonehenge Heather opened with a talk titled ‘Stonehenge, Archaeoastronomy and the Moon’. She told us how prehistory and astronomy is a very interesting subject, Stonehenge has played a huge part in the discipline of archaeoastronomy. William Stukeley was the first to see the alignment with the Sun between the circle and the Heel stone at Stonehenge, observing the Summer Solstice in 1724. Norman Lockyer then publishes his work on astronomy and the circle in 1909. Later work was undertaken by Alexander Thom, Fred Hoyle (1977), Gerard Hawkins and most recently Prof Clive Ruggles. The circle sits in a wide and complex landscape from which monumental remains date through a highly complex timeline which extends millennia. The Curses and long barrows are from the early Neolithic when the first farmer came in the UK. Whereas the circle and avenue come from a slightly later period. In the final stage several barrows were added by an even later population who brought metal working with them. The circle is made from a ring of blue stones which were transported from Wales and the large dense sandstone Sarsens. 3D scanning has shown that every stone has been worked to a high standard and the it certainly was a Temple to the people who used the site. Acoustic work has shown that the Blue stones ring when stuck. It seems that the mid-winter sight line was the most important and we were shown several images of this in practice and told that the Heel stone may have had a partner which together would have framed the rising Sun. There are four station stones which are in the ring ditch and predate the circle, these form a rectangle and create sight lines for the lunar standstill positions, there are a number of cremated remains on one of the lunar standstill sightlines which may have been placed while a period of standstill was in action. All the astronomy sight lines including the lunar ones are now protected. Stonehenge has a new skyscape feature, which you can view the sky at Stonehenge all year round. You can try the feature here: https://www.stonehengeskyscape.co.uk/
The second talk by Alexandra Loske and Robert
Massey was on the theme of their recent book ‘Moon: Art, Science, Culture’. We
were treated to a wonderful visual history of the Moon and what it meant to artists
and how this work overlapped with science. The Moon has been depicted from the
earliest history, with lunar phases being drawn on the walls of the Lascaux
The Bronze Age Nebra Sky disc was shown next, this wonderful object from the German Halle Museum will be making a trip to the UK for the British Museum Bronze Age exhibition in 2021. It has a UK connection as all the tin and gold in the object stems from Cornwall. Jan Van Eyck’s painting of the crucifixion shows perhaps one of the first real depictions of the lunar surface in a correct phase. William Gilbert produced the first Moon map in 1603 just before the use of the telescope. The telescope transformed our relationship with the Moon with work by both Thomas Harriot and Galileo Galilei both drawing very early sketches of the Moon. By the 18th century the Lunar Society was formed, and people travelled to meetings under the Full Moon. Caspar David Friedrich regularly uses the Moon as a centre piece for his images in the 19th century. Steeped in symbolism he sets his paintings in a Sublime landscape with human figures often with their backs turned and off to one side, drawing the eye in to the Moon itself. By the late 19th Century photography started to transform our relationship with the Moon and new accounts of journeys into space were written by Jules Verne and H.G. Wells. They introduced the spacecraft as a believable object. It was only one year later after H.G. Wells book that there was the first moving image of the Moon by George Méliès. Another influential film ‘Frau im Mond’ (Women in the Moon) was one of the final silent films on the cinema. The film premiered on 15th October 1929 and features wonderful ideas such as multistage rockets and invented the countdown to liftoff. Finally, Robert and Alexandra spoke at length about the Apollo missions, talking about how science has come on to change the space program and how the visits to the Moon gave us a greater understanding of the formation of the Solar System. The book on which this talk is based can be found here: Moon
After the lunch break Bill Leatherbarrow
introduced us to his topic Patrick Moore and our Volcanic Moon. He reminisced
with fondness, how Patrick would always say ‘once a moon man – always a moon
man’ even at the most inappropriate moments. Patrick first love was the Moon
and he wrote over 100 books on the subject. He was one of the BBC’s reporters
covering the Apollo missions. His first and his last submissions to the British
Astronomical Association were also about the Moon. The first was published in
1946 and was about craters on the Moon. Nearly all his life he felt that the
craters on the Moon were to do with volcanic activity, rather than bombardment
from outer space. He clung to the theory for much of his life, even though
Ralph Baldwin published with his correct meteor theory in 1949. Patrick was convinced he was correct and that
through a telescope he could see evidence of volcanism. The first piece of evidence
was that the craters were all round. (this has been debunked as astronomical
impacts are an explosive event which involves a high amount of kinetic energy
and leave a single point of explosion, creating a round crater.) Patrick
claimed the distribution showed chains of volcanos. (this is due to objects
fragmenting much in the way Shoemaker Levy 9 did when it hit Jupiter.) He also
said that small peaks had craters on the top and this showed volcanic vents, he
felt that this was too obvious a target and should not happen all the time.
(This is due to lighting and the position of the Sun and these craters when
imaged were not there). Finally, he claimed that you could not expect all the
big impacts to come first and the smaller ones second. (This is what you can
expect as them larger space debris hit the moon first and then only smaller
debris was left to hit the moon at a later period). Patrick was a great friend
with his BAA Lunar Section Director predecessor, H P Wilkins who was also a
great advocate of the crater/volcano theory. He was probably heavily influenced
by this man in this instance in his early career. Patrick would be passionate
about transient lunar events all his life and volcanism offers something which
is exciting as events could still happen, whereas the impact crater theory is
talking about something which is historical and possibly of less interest to an
active observer of the Moon. The Moon has witnessed volcanism in the past, it
would not have lasted for a long period of its history due to the loss of its
internal heat because of the size of the Moon. The bright areas of lunar
highlands are the original crust of the Moon from 4.4 Billion years ago and the
seas come from a later process of volcanism where magma filled basins just 2.5
billion years ago. There are also a couple of volcanic craters, but these have
no rims and they are surrounded by dark ejecta. This can be seen on the Hyginus
crater. Bill’s 2018 book called ‘The Moon’, can be found here http://www.reaktionbooks.co.uk/display.asp?ISB=9781780239149
Next, Melanie Vandenbrouck and Louise Devoy spoke
about the current Moon exhibition being held at the Royal Museum Greenwich. The
exhibition explores humanities relationship with the Moon through Science, Humanities
and Arts. They looked at collections within the UK and the Smithsonian and from
700 objects they selected 180 to feature in the four-room exhibit. The whole
exhibition was five years in the making.
The exhibition opens with a tiny etching by William
Blake which shows a figure who is going to climb a ladder to the Moon. This, they
felt, mirrored our dreams and aspirations of our relationship with the Moon
which has been a constant companion, timekeeper and often spiritual object. The
Moon has permeated all cultures, at all times through history. The first area
looks at how we have observed the Moon through history, it houses everything
from a Babylonian tablet discussing a lunar eclipse to an astrolabe which has
been dismantled to show its interior workings which has a lunar section
demonstrating the phases on the Moon. The astrolabe has one of the oldest
geared system in the world. The room also shows how we have connected to the
moon through religions such as the Hindu god Chandra. The second area looks at
how humans’ idea of the Moon transformed once they could see through a lens. It
includes a 20inch telescope which is so large it had to be placed in the room
and then the rest of the exhibition was built around it. The collection
includes how important developments were made through photography and how
lantern slides brought this to the masses. Area three is called Destination
Moon this looks at both fictional and actual travel to the Moon, they explore
how Science and the Arts work together such as through the film ‘Frau im Mond’.
This room also shows how popular culture gets in on the act with clothes and
designs which include lunar themes. The number of people who were involved with
the space race and the launch of the Moon missions are commemorated with several
images. The power of images has been recognized as the US program took over 32,000
whereas the less well remembered Russian missions took very few. The final
sector is ‘For all mankind?’ It reflects on what’s happened since Atlas program
was cancelled. Topics such as ‘who owns the Moon’ are explored, it also looks
at when we are going back and what science may be able to learn from a return
to the Moon. The final object in the exhibition is the iconic photograph of Earthrise
taken on Christmas 1968, which acts as a mirror and reflects our dreams,
passions and desires. More about the exhibit and how to see it can be found
The final talk of the day was by the SHA
President Allan Chapman. His talk was entitled ‘The Moon, the Telescope and the
Transformation of Astronomy after 1609’. Allan opened his talk with his condolences
over the sad loss of Stuart Williams and remembered his great contribution to
the Society in its early years.
Allan’s talk opened with an image drawn by Thomas
Harriot of the Moon, which is dated 1609 July 26th at 9pm. The image
is very special as it not only is the first sketch of the Moon through a telescope,
but it unusually has a time on it. The Moon it shows is just five days old and
it totally overthrows all earlier ideas of the moon. The Moon up to then had
been smooth a celestial body and demonstrates perfection. Harriet finds a
jagged terminator rough not smooth. Why did he not publish, Allan explained
there are several reasons. Harriot was a rich man he was a mathematician and astronomer.
The political situation was volatile. Just four years before his friend Lord
Percy had been in the tower, he was not looking for fame as had also been taken
to the tower, he had lands in Ireland, in the north of the UK and an annual
income of £200. His papers were not discovered until 1784 in the Petworth house
archives. They showed that Galileo was not the first to draw the Moon as his
drawing came on November 30th, 1609. Galileo publishes quickly in
1610, he wanted money and fame, but in doing so he struggled to adjust to the
higher society circles and rubbed a lot of important people up the wrong way,
which gets him into trouble. This use of the telescope was the first time that
a one of our five senses became enhanced. The Polish Astronomer, Johannes Hevelius,
was also a rich man (from the brewery industry) but he was interested in
astronomy and he draws the phases of the Moon in 1640, the craters in 1645 and this
develops the into the first lunar atlas. Allan then moved onto the work of Rev
Dr John Wilkins who was from Wadham College Oxford and thought that we might
soon be able to fly to the Moon and what’s more, it may be inhabited. The
telescope was allowing people to see objects in the sky as worlds for the first
time. Robert Hooke would work with Wilkins and they would build mini flying
machines with spring motors, these are most likely the first flying machine
ever built. They thought that they just needed to upscale the model and they
could then travel to the Moon. By 1672 Wilkins knew it was impossible to travel
to the Moon as Boyle had shown space would not be breathable by making a
vacuum. (air pressure at altitude). Hooke also devised an idea about a
telescope with a ½ mile focal length from which he felt you could observe the
surface of the Moon as clearly as you could see sheep on Salisbury plain. By
1665 he starts to talk about structure of lunar surface in his book ‘Micrographia’.
Allan then spoke about the Great Lunar Hoax which is attributed to Richard
Adams Locke. This showed that people were still not looking at the Moon in any detail.
This would come later with a great chart of the Moon by Dr John Lee and early
photography. More about the Lunar Hoax can be read in Bulletin 32 written by Carolyn
This brought us to the end of a very interesting
day of talks both formal and informal. We wish to extend our thanks to all the
speakers for an interesting and varied day all about the Moon. Thanks also to
James Dawson and his helpers for the always fascinating book stall. We also
wish to thank all the attendees for battling through the inclement weather to
make it to the BMI that day.
The Society’s Annual General Meeting was held on the 27th October 2018 at our adopted home, the BMI Birmingham. It was a cold start to the day but nevertheless the event was still well attended with over 75 members and guests arriving to hear the proceedings and speaker line-up of the day. Bob Bower opened the event as Chair, this was his last event in this position as he had decided to stand aside after a number of years in the role. He was instrumental in increasing the membership to its current high levels. Bob was thanked for all his hard work and we will continue to see him at meetings as he is one of the organisers and speakers of the two day Oxford Conference in April 2019. The minutes were approved and the council welcomed the new Chair Gerard Gilligan to his post. Gerard is well known to members as his prior role was membership secretary. The vacant position of membership secretary has been filled by Graham Jones, and we welcome him to the council for the first time. Graham is an experienced astronomer who is also on the council of The Society for Popular Astronomy.
The annual awards were presented as follows; The Roger Jones award for 2018 was awarded to Brian Jones, who unfortunately could not make it on the day, but was being recognised for his fantastic work on the SHA Facebook page, where he posts interesting historical facts on a daily basis. The Madeline Cox award was given by the Bulletin Editors to Graham Mcloughlin for his article on the 1927 Solar Eclipse and all the research that he has done on the subject. Mike Leggett was awarded the Peter Hingley award for all his work on the council and within the society. Mike is a founding member of the society and a long term member of the council. He most recently held the post of Publicity Officer, due to work commitments he has had to step down from the council but will still be a regular attendee of the society’s meetings. Well done all.
Andrew Stephens, the first speaker of the day took us on a journey to our neighbouring galaxy Andromeda. His talk “Observing the Andromeda Galaxy, Dec 1612 to date-a warps and all story!” introduced us to a research project which he has been undertaking since September 2015. It was during the night of the supermoon total eclipse when Andrew observed Andromeda in what he felt were exceptionally transparent conditions. Through binoculars he was surprised to see large, unfamiliar, areas of nebulosity at the galaxy’s extremities. He noticed these areas were off-axis with respect to the major axis of central bulge and at the southern end showed signs of having a three-dimensional structure. Researching these features has proved fascinating, as many excellent observers throughout history make no reference to them. The observations can be explained by reference to professional findings concerning the tidal warping of the galaxy. Although Andromeda is usually reported as visually symmetrical Andrew believes it is not. During the talk he demonstrated warping can easily be seen on any photograph if it is turned so the major axis of the galaxy lies on the horizontal. He finished with a request that anyone finding references to visual observations of the warping, or observing it for themselves, please get in touch, as it will add to his ongoing research. After introducing us all to this riveting mystery I am sure many of us will be observing the galaxy in a whole new way.
Rob Peeling took the floor to guide us on a story through the life of Admiral William Henry Smyth, with a talk entitled “William Henry Smyth, his life, placing his astronomical work in the wider context of his participation in British intellectual life in the 19th Century.” His early life was marred by his father finding himself on the losing side of the American War of Independence. This meant that the family found themselves in a reduced state in the UK and his father’s later return to America to try and reclaim some of the family fortune ended with his tragic death. He would never meet his son, who was born in the UK just months after he died. Smyth at the age of 14 took matters into his own hands and joined the Navy, against his families wishes. His life was adventurous and he travelled to many far off places and was involved in a number of conflicts. Best known for his 1844 book “A Cycle of Celestial Objects”, he was also an excellent self-taught cartographer. Many of his observations were made in his observatory at No 6 The Crescent in Bedford, there is now a Blue Plaque on the property. We thank Rob for this wonderful synopsis on Admiral William Henry Smyth life, he certainly led an exciting life.
After lunch we had a new feature to our proceedings, we held our first short talk hour, this hour was split between three twenty minute talks. We hope this will allow people to present smaller areas of research without feeling the need to have to present for an hour. Bob Bower opened this section of the meeting with a talk entitled “ The artistic skills of Lord Rosse – His hitherto unpublished drawings”. The slides gave us an opportunity to see some of the wonderful sketches that Lord Rosse peppered throughout his notebooks, many which have not been seen before outside of Birr Castle. Lord Rosse’s drawing skills were excellent and his humour abound throughout the sketches. We also got to see images of Bob’s visit to Birr Castle, along with the huge Leviathan telescope, this is a replica telescope which can still be seen by visitors to the castle. After hearing Bob’s wonderful talk I am sure many of us will be inspired to visit this amazing location.
John Chuter and Eddie Carpenter then spoke about “Sir Robert Stawell Ball”. Many of the attendees will have made the link to the BMI and Ball, with the SHA library being called after this foremost communicator of popular astronomy. John began with a brief summary of Sir Robert’s life, and then went on to explain how he had made extensive use of lantern slides. Sir Robert had kept detailed notes of his lectures which included lists of slides he had used. John, as Co-archivist of the BAA had come across the remnants of their once large lantern slide collection they loaned out to members. His research shows that Sir Robert had left his lantern slides to the BAA. The BAA had decided to dismantle the collection in the 1980s. Eddie has purchased a large number of them at that time. There is still a lot of work to do on this, but it is possible that a number of Sir Robert’s slides are still in the BAA’s or Eddie’s collections. Eddie and John have made some educated guesses on which they are. We were then treated to a lantern slide show by Eddie showing possible slides owned by Sir Robert. Over 1 million people saw Ball lecture in his life. He never changed the slides himself, always relying on paid Lanternists to do this, to ensure the smooth running of the show, without the encumbrance of slides being put into the machine upside down or the wrong way around. Ball gave his last lecture around 1910 using lantern slides, maybe some of which we saw today. It is always wonderful to see the old lantern slide machines in action, and we thank John and Eddie for the talk and accompanying presentation.
The following full-length talk was given by Graham Mcloughlin on “The 1927 Solar Eclipse.” This eclipse was on 29th June and had a central line through Lancashire and North Yorkshire. Graham described how it was the first full eclipse in the UK for 203 years and was highly anticipated by astronomers and the general public alike. Graham showed a large amount of material from that year which demonstrated how people would be travelling to the eclipse region. With an eclipse area of just 30 miles width and totality being only seconds, people had to choose their observing location with care. Unfortunately June 1927 was befallen with poor weather, demonstrated with the outfits people wore in the images, many being in overcoats with hats and scarfs. Witnessing totality was a lottery with people located just miles apart being clouded out or under clear skies. Graham brought many photographic slides of the event which gave us a real feel for the excitement of the build-up and the event itself. Thank you Graham for showing us that eclipse chasing is nothing new and giving a wonderful talk about a very interesting event here on UK soil.
After the final break and a last look around the library and book stall, delegates were treated to the exuberant Allan Chapman and his talk “The Wonderful Century; From Atoms to Island Universes. Astronomy in the 20th Century.” Allan is the societies honorary president and is always very supportive, regularly speaking at the October AGM. This year we were treated to a journey through the 20th century. Starting with Sir Norman Lockyer and his discoveries of Helium, we journeyed through the fastest developing period in astronomical history. Allan covered everything from Williams Huggins spectroscopy and how this had opened up new fields at the start of the century, to Albert Einstein’s development of a whole new physics with his work on relativity. We also heard about the work of Henrietta Swan Leavitt and the classification of stars and Edwin Hubble and the realisation that galaxies were redshifting and moving away from each other. We were brought right up to the end of the twentieth century with Allan sharing wonderful stories about his meetings with Patrick Moore and Barnard Lovell. This lecture was a real treat and it was wonderful to hear all about the lives of these trailblasers.
We thank all the members and guests for attending the meeting and hope you enjoyed the day. See you all April 2019 at our Spring Conference in Oxford.
The Society for the History of Astronomy Spring conference was held at the Institute of Astronomy, Cambridge on the 21st April 2018. A record number of 108 delegates were warmly greeted at the door by the SHA meetings organizer Dennis Osbourne.
Initial introductions and a brief welcoming talk was given by the SHA Vice-Chair David Sellers. He expressed that the talks had a wide range of subject matter from forgotten star atlases, archaeoastronomy, history of astrophotography, and Admiral William Henry Smyth and there should be something which would appeal to everyone in attendance.
The day’s events would start with a trip to the far south west of the UK looking at the Archaeoastronomy of Cornwall. This talk was given in two parts. The first half about West Penwith and the Isles of Scilly was delivered by Carolyn Kennett and the second half about the Hurlers and Bodmin Moor was by Brian Sheen.
Carolyn explained how archaeoastronomy has a real relevance to these areas and there are many monuments ranging from the Neolithic to the Iron age which show evidence for alignments in West Cornwall. There have been several studies conducted within the region, these include work untaken by Edwin Dunkin, Norman Lockyer and most recently Michael Hoskins. The talk gave a quick introduction to the methodology used when looking for alignments and how there is evidence for both solar alignments and lunar alignments in the stone circles in West Penwith. The Isles of Scilly is more complex in nature and although several barrows are known to align with the summer solstice sunrise many do not seem to follow this pattern. Carolyn then moved far further forward in time to the Iron age, explaining how Fogous found in the far south west were aligned to the summer solstice sunrise.
Brian Sheen spoke about the evidence on Bodmin Moor. He has spent many years working at the triple stone circle site The Hurlers. He explained how this is a complex site, although there is a solar aligned circle Cradock Moor within the immediate locality. The circles at the Hurlers has been the focus of a few projects trying to unpick its secrets, these have included a reexamination of the interlinking pathway, the discovery of the single menhir in the position of a possible fourth circle (now defunct idea). All this has enabled a deeper understanding of the archaeoastronomy of the site. More about this work is included in this Bulletin 30.
The following talk by Kevin Kilburn on the John Bevis’ “Uranographia Britannia” the forgotten Star Atlas, was a fascinating tale of a lost masterpiece and how through diligent research, the evidence has been pieced back together of what transpired to the original Atlas and a large number of printed pages. Only three intended Uranographia Britannica are known and these are incomplete. The ambitious project had been financially backed by John Neale, who subsequently became bankrupt. The project was incomplete, and all the printing plates and pages were taken to pay his executors. Apart from the original three Uranographia (known to exist) large number of printed pages were put together to form a near complete Atlas sold in 1786 as Atlas Celeste. A copy of Bevis Atlas Celeste has been discovered by Kevin Kilburn in the Manchester Astronomical Society library. All the other known copies of Bevis Atlases can be seen on the societies website. http://www.manastro.co.uk/bevis.html We thank Kevin for a very interesting talk.
During the break for lunch many delegates took advantage of the warm summer day and were able to eat their lunch on the lawn, Rob Peeling also gave a short talk about his ongoing research into the life of Admiral William Henry Smyth. Rob Peeling had searched through the Hartwell papers held by the Royal Astronomical Society. In a box of correspondence between the Smyths and Dr John Lee, he found a soft covered book of observations which he initially assumed were by Smyth. However, inside the front cover was written, “In a letter to my nephew, J. Herschel”. The date on the front cover was 1783. The observations were the first by Caroline Herschel (the book is actually excerpts from another original journal. This book has not been seen since before 2014 and was feared to be lost. The observations cover the period in which Caroline discovered or independently re-discovered all 14 of the clusters and nebulae attributed to her. Rob showed a number of these discovery records and how they are often accompanied by the phrase, “Messier had it not”. The first page of the book includes Caroline’s instructions from her older brother, William on what he wanted her to record. This is under the heading, “to be wrote down”. Caroline also recorded the conditions she observed under, including the evocative, “ice on tubes”.
Nik Szymanek was the first speaker after the lunch break. He covered the topic of the History of Astrophotography. His talk explored the early forays and successes that historic astrophotography’s such as Henry Draper and Edward Emerson Barnard. In 1959 amateur astrophotography’s started by using black and white film to image the night sky. Nik showed wonderful images taken by amateurs through the ages. Explaining the developments of the technology and how this has improved the results to the current day. He peppered his talk with personal successes and sometimes failures that he had along to way. Astrophotography is Nik’s passion and his deep knowledge in the subject shone throughout this fascinating talk.
The next speaker was Jonathan Maxwell who spoke on “Some Lesser Known Aspects Regarding the Evolution of Refracting Telescopes: Lippershey’s spectacle lenses to the Apochromats”
Around about 1730, Chester Moor Hall invented the first achromatic doublet lens. This was a major turning point in the development of telescopes and a spectacularly successful invention which has been a foundation stone on which all optical instrument industries, not only telescope making industries, have depended on ever since. A lot of interesting lesser known developments happened in the evolution of refracting telescope objectives before Chester Moor Hall, and a lot of similarly interesting things happened afterwards too. The history of some of these developments are not as well understood as we might wish.
Long before Chester Moor Hall, Ibn Sal in 984ad (a Persian scientist working in Baghdad) determined the geometry of refraction in transparent materials (“Snell’s law”) which enabled him to design conic aspheric surfaces to remove spherical aberration in lenses, for the purpose of improving the efficiency of burning using the Sun’s rays. These surfaces became known as Cartesian Ovals, named after the 17th century philosopher Descartes, who promoted them as being his invention.
Thomas Harriot re-discovered Snell’s law in 1602, but probably didn’t know about Cartesian Ovals. Descartes, fairly certainly, got to know about Snell’s law and Cartesian ovals from Snell around about 1621 (this is still debated). Snell was a professor of Mathematics and had studied Arabic texts on optics, and it is possible that he got his law, and the knowledge of Cartesian Ovals from either an original Arabic manuscript of Ibn Sahl, or from a Latin translation of Ibn Sahl’s work. Snell died in 1626.
From about 1630, Descartes propagated the knowledge of “Cartesian” Ovals to savants of astronomical telescope manufacturing, in particularly the use a convex Hyperbolic curve on their objective lenses. But hyperbolic curves were very difficult to grind and polish at that time (and, like all aspheric surfaces, still are), and what is more, from the lens design point of view, a hyperbolic curve introduces massive amounts of Comatic aberration, and of course does not correct Chromatic aberration.
However, in 1660, Christiaan Huygens told Christopher Wren that he had discovered that a combination of a convex and a concave lens could correct spherical aberration, thereby releasing the telescope optics community from the heavy yoke of hyperbolic curves and opening the door for Chester Moor Hall’s invention of the achromatic lens, and possibly opening the door for Robert Hooke and Isaac Newton’s understanding of chromatic aberration correction in lens systems.
At this point in the talk a major controversial topic was introduced: did or did not Newton know that chromatic aberration could be corrected in lens systems? Certainly, Newton publicly proclaimed that Chromatic aberration could not be corrected in lens systems, but, reviewing the literature about this (Newton’s optical work) a strong case emerges for Newton knowing that it could be corrected in lens systems. The speaker showed illustrations from Newton’s works, and one constructed from the words in one of Hooke’s works, showing that both men were close to knowing that chromatic aberration can be corrected in lens systems.
Why did Newton not make this publicly clear? The speaker’s opinion was that It may be that Newton was not quite sure about it in his own mind, or it may be that he didn’t want to admit that Robert Hooke was correct when he said (of Newton’s reflecting telescope) that there was no necessity for reflecting telescopes!
Jonathan then dealt briefly with some interesting but well-known developments in the late eighteenth and early nineteenth century to do with liquid lenses (such as had been used by Newton and Hooke) by, notably, Robert Blair and Peter Barlow. He went on to about two neglected heroes of the Victorian era: William Wray who had worked the optics of two major telescopes for James Buckingham (that were the largest aperture refractors in the 1860’s), and an apochromatic lens that used baked resins instead of flint glass. And the Reverend Vernon Harcourt who, from 1834 to 1872 (when he died) worked with George Gabriel Stokes to develop glasses that could correct Secondary Spectrum in telescope objectives. In that work Harcourt tried just about every possible chemical in glass melts. After he died George Gabriel Stokes published a paper explaining Harcourt’s indefatigable work and was then approached through an intermediary to explain Harcourt’s work to a Professor Abbe of Jena…In 1886, the Schott/Zeiss glassworks published their first glass catalogue, based on much of the chemistry that Harcourt had investigated.
Finally, Jonathan talked about a better-known hero of the Victorian era: H. Dennis Taylor of the T. Cooke and Sons company in York, who in 1892/93 published patents for two very different triplet lens systems. These were a Photo-Visual (apochromatic) lens (the first apochromatic telescope objective) deploying some of Schott’s new glasses, and a flat field anastigmatic lens that was advertised for wide field astronomical photography, but which also found a home with the Taylor, Taylor & Hobson Company in Leicester as a general photographic lens.
The afternoon break gave the attendees their final opportunity to look at the book sale that James Dawson, the SHA librarian, had organised. There were many books for sale, all from the field of astronomy, with lots of them about the history of astronomy. This was a well received and great addition to the spring conference.
The last session of the day was filled by Rob Peeling and Bob Marriott. Rob Peeling spoke first about Captain William Henry Smyth. In 1844, Captain William Henry Smyth published the Cycle of Celestial Objects, including the Bedford Catalogue. Smyth’s observing notes for each of the objects are as fresh and relevant today as they were 174 years ago. They remain a valuable companion for those wishing to develop their visual observing skills. However, there is a constraint. Owing to the early date of publication Smyth uses 1840 epoch coordinates together with object designations that are now obsolete. These include designations by William Herschel and from John Herschel’s Slough catalogue and Piazzi’s Palermo star catalogue. It is therefore difficult for a modern observer to check which object is being referred to. Rob Peeling precessed the Smyth’s position data to epoch 2000.0 and using various techniques has identified all 850 objects in the Bedford Catalogue together with any other objects or stars mentioned in Smyth’s note. It is now once again possible to hone one’s observing skills with Admiral Smyth as your companion and guide. The updated Bedford Catalogue can be found on the Webb Society’s website at https://www.webbdeepsky.com/publications/free/.
Bob Marriott then spoke on ‘The Silver-on-Glass Revolution.’ The arrival in the 19th century of glass telescope mirrors coated with silver, was a revolution for amateur astronomers because, almost suddenly, they could make large and small telescopes much more conveniently. Since the invention of the reflecting telescope in the 17th century, mirrors had been made of speculum metal – an alloy of copper and tin that could be polished to produce a reflective surface. Speculum metal is much heavier than glass and tarnishes quickly, and mirrors required frequent re-polishing. The process of production of silver involving silver salts, aldehydes, and sugars was discovered in the early 1830s by the German chemist Justus von Liebig. The silvering process was developed over many years and numerous patents were registered by many researchers, but it was applied primarily for decoration and ornamentation and it was not until the 1850s that a sufficiently fine and stable silver deposit could be produced that was good enough for astronomical purposes. The first telescope with a silver-on-glass mirror was built in France by J. B. L. Foucault in 1857. Two years later, Henry Cooper Key and George With, both of Hereford, made the first silver-on-glass mirrors in England, and in the early 1860s George Calver began commercial production of silvered mirrors. Over many years, With produced about two hundred mirrors, while Calver established a business and produced countless numbers of mirrors and complete telescopes – a business that he maintained for sixty-five years until his death at the age of 93 in 1927. The deposition of silver on glass remained the standard technology for telescope mirrors for seventy years, until the advent of aluminium coatings around 1930.
The SHA would like to thank all the speakers for their informative and extremely enjoyable talks. It was lovely to catch up with lots of familiar faces and also to welcome 3 new members who signed up on the day. We look forward to seeing you all again at the summer picnic on Saturday 30th June at the Seething Observatory, Thwaite St Mary, Norfolk.
Text: Carolyn Kennett, John Chuter, Rob Peeling, Jonathan Maxwell, Bob Marriott
Images from Kevin Kilburn, Laura Carroll and John Chuter