Eighteenth-century eclipse maps by Halley and Whiston

Earlier this month I published a post at the H Word on ‘Halley’s Eclipse’ of 1715. It has been associated with Edmond Halley because, using the best theory and data then available, he made impressively accurate predictions of its timing and path, publicised through a broadsheet map and the Royal Society. As I explain in the post, however, he was not the only one to do so: London was a competitive market for scientific publications and authority.

This post is an appendix, where I can show more of the eclipse maps published than I could on the Guardian’s website. I should add, too, that these were not the first predictions or maps of solar eclipses, and that there were earlier German, Dutch and French maps.

Here, however, is Halley’s first map, from Eclipse Maps, which was published in advance of the event, encouraging observation. It is titled “A Description of the Passage of the Shadow of the Moon over England, In the Total Eclipse of the Sun, on the 22d Day of April 1715 in the Morning”. I am not sure where the original is kept, but it may be the same as that reproduced in black and white in Jay Pasachoff’s article on Halley’s eclipse maps, which is from the Houghton Library. The full text, which is not high enough resolution to read here, has been transcribed by Pasachoff.

Halley's predictive map of the 1715 eclipse, from Eclipse-Maps.com.
Halley’s predictive map of the 1715 eclipse, from Eclipse-Maps.com.

Halley seems to have produced more than one edition of the map before 22 April 1715 (O.S. – the anniversary was celebrated on 3 May N.S.), and also one after the event, showing the path as corrected by observations. This copy of his “A Description of the Passage of the Shadow of the Moon over England as it was Observed in the late Total Eclipse of the Sun April 22d, 1715 Manè” is from the Institute of Astronomy, University of Cambridge, where you can see some superbly high-resolution images.

Halley's map of the 1715 eclipse, produced and corrected after the event. Institute of Astronomy, University of Cambridge
Halley’s map of the 1715 eclipse, produced and corrected after the event. Institute of Astronomy, University of Cambridge

Halley came back to his winning formula when another eclipse rolled along. His map, published in 1723 (annotated November 17123 here), showed both the recomputed path of the 1715 eclipse and the predicted path of 11 May 1724. This image is from the Houghton Library’s Tumblr, where it is available in higher resolution. The text declares that the first map “has had the desired effect” in encouraging observation and uses this one to demonstrate that his predictions had been pretty good in 1715 and were worth acting on again.

Halley's map showing the 1715 and 1724 solar eclipses. Houghton Library (EB7 H1552 715d2b).
Halley’s map showing the 1715 and 1724 solar eclipses. Houghton Library (EB7 H1552 715d2b).

However, as my post discussed, William Whiston was also in the business of predicting eclipses and selling scientific paraphernalia.  Like Halley, he was making predictions based on John Flamsteed’s observations at the Royal Observatory and corrected with Isaac Newton’s theory, and encouraging observations. Whiston made comparison of his observations with Halley’s and his  two eclipse-predicting broadsheets are again from the Cambridge Institute of Astronomy’s Library here and here.

The one I think is the earlier from Whiston was dated 2 April 1715 and titled “A Compleat Account of the great Eclipse of the Sun which will happen Apr. 22 in the Morning”. It is much more text-heavy and technical in content, and the map is a celestial one, showing the positions of the heavenly bodies rather than the path of the shadow on Earth.

Whiston's broadsheet predicting the timing and path of the 1715 comet. Institute of Astronomy, University of Cambridge (AMI/11/B).
Whiston’s broadsheet predicting the timing and path of the 1715 comet. Institute of Astronomy, University of Cambridge (AMI/11/B).

A second broadsheet by Whiston did show the Sun’s shadow on the Earth, but from a global point of view. The title too emphasised that this was not just an English matter: “A Calculation of the Great Eclipse of the Run, April 22d 1715 in ye Morning, from Mr Flamsteed’s Tables; as corrected according to Sr Isaac Newton’s Theory of ye Moon in ye Astronomical Lectures; with its Construction for London Rome and Stockholme”. It also advertised an instrument that could be bought from Whiston.

Whiston's second 1715 eclipse broadsheet. Institute of Astronomy, University of Cambridge (AMI/11/C).
Whiston’s second 1715 eclipse broadsheet. Institute of Astronomy, University of Cambridge (AMI/11/C).

John Westfall and William Sheehan’s new book on observing eclipses, transits and occultations, indicates the Whiston and Halley’s estimates varied by about 25 miles, which perhaps puts the more triumphant claims of accuracy in perspective. I think (correct me below if I am wrong) that Halley’s prediction was the more accurate, but there was an element of luck involved. Above all, his map, showing geographical detail of England beneath the path of totality, was much more persuasive and appealing – this is the main reason that the 1715 eclipse became ‘Halley’s’.

Whiston had learned the importance of the image by 1724. His “The Transit of the Total Shadow of the Moon” this time showed familiar coastal outlines, although again other parts of Europe were included: Paris would be a better observing site than London this time. This version is from the Science & Society Picture Library and belongs to the Royal Astronomical Society.

Whiston's map showing the predicted path of the 1724 eclipse. Science & Society Picture Library/Royal Astronomical Society.
Whiston’s map showing the predicted path of the 1724 eclipse. Science & Society Picture Library/Royal Astronomical Society.

And so the maps continued: there are many to explore in the wonderful albums at Eclipse Maps. It was a flourishing business come eclipses in the 1730s and beyond, especially that of 1764, as many publishers jumped on the opportunity that Halley and Whiston had spotted in 1715. So too, of course, had the person that links all the images shown here: the engraver and cartographer John Senex, who deserves a much fuller biography on Wikipedia than this!

 

Maskelyne: Astronomer Royal – book now available

Now available from the publisher, Robert Hale Books currently cheaper than AmazonMaskelyne: Astronomer Royal has been edited and partly written by me, with contributions from seven other curators and historians of science.

9780719809125

 

Stemming from a public symposium at the National Maritime Museum in 2011, marking the bicentenary of Maskelyne’s death, the book aims to be readable. It is also very well illustrated, particularly with photographs of objects, drawings and papers from the Museum’s Maskelyne collection. The full contents are as follows:

Introduction (Rebekah Higgitt)

Chapter 1: Revisiting and Revising Maskelyne’s Reputation (RH)

Case study A: The longitude problem (RH)

Chapter 2: ‘The Rev. Mr. Nevil Maskelyne, F.R.S. and Myself’: The Story of Robert Waddington (Jim Bennett)

Case study B: The projects of eighteenth-century astronomy (RH)

Chapter 3: Maskelyne the Manager (Nicky Reeves)

Case study C: The Astronomer Royal at Greenwich (RH)

Chapter 4: Nevil Maskelyne and his Human Computers (Mary Croarken)

Case study D: Maskelyne and the marine timekeeper (RH)

Chapter 5: Maskelyne’s Time (Rory McEvoy)

Case study E: Instruments of exploration (RH)

Chapter 6: ‘Humble servants’, ‘loving friends’, and Nevil Maskelyne’s Invention of the Board of Longitude (Alexi Baker)

Case study F: The Royal Society and Georgian science (RH)

Chapter 7: Friend and foe: The Tempestuous Relationship Between Nevil Maskelyne and Joseph Banks (Caitlin Homes)

Case study G: Visualizing and collecting the Maskelynes (RH) 

Chapter 8: The Maskelynes at Home (Amy Miller)

Coda: A life well lived (RH)

Picturing science: Mapping the moon

A reproduction of a lunar map by H. Percy Wilkins, a “proto-Patrick Moore”, is on display at the National Maritime Museum. It makes an interesting side-show to the new major exhibition, Visions of the Universe. [Cross-posted from The H Word blog.]

Map of the Moon by H. Percy Wilkins
Sheet from 1951 ed. of Wilkins’ Map of the Moon. Source: National Maritime Museum

Given my recurring Picturing Science posts in this blog, I can’t avoid mentioning the new exhibition that has opened at the National Maritime Museum, Visions of the Universe. (Full disclosure: I have not been involved with this exhibition at all.) It has been getting some really nice reviews and previews, and anyone with an interest in astronomy or photography should make the trip.

Visions of the Universe exhibition at the National Maritime Museum

In this post, though, I want to highlight something else that is currently on view, within the main (free) museum. While the exhibition showcases what the space age has brought us, with extraordinary Hubble-type images and – the real hit, I think – a 13-metre long Mars Window, this other display offers the clearest possible reminder of how recently it is that any of this became possible.

In the NMM’s Compass Lounge (at the rear left of the Museum’s new entrance foyer), the several sheets of a 1951 map of the moon have been photographed and reproduced to show the complete 300-inch chart. It shows an extraordinary level of hand-drawn detail, achieved by its maker, H. Percy Wilkins (1896-1960), with the aid of distinctly earth-bound telescopes.

This map, versions of which he had been working on since the 1920s, was the largest-scale and most detailed of its time, combining Wilkins’ personal observations with data from the drawings, photographs and measurements of other astronomers. As his Wikipedia entry says, it was “considered by some as the culmination of the art of selenography prior to the space age”. Wilkins himself described it as “the World’s greatest Moon Map”.

The map was also, perhaps, one of the last productions of its kind. Not only was it published just on the cusp of the space age, but it was also the project of an amateur, working from his home near Bexleyheath with a 12½-inch, and later a 15½-inch, reflector. Wilkins did the work in his spare time, being employed first as a mechanical engineer and then a civil servant at the Ministry of Supply.

Title page of Wilkins' Map of the Moon
The title page of Wilkins’ Map of the Moon. Source: National Maritime Museum

Wilkins nevertheless found time to make telescopes, publish several works on popular astronomy and act as director of the British Astronomical Association’s Lunar Section. As well as founding the Section’s periodical The Moon, he was also, late in life, the first president of the International Lunar Society.

Two of Wilkins’ books were co-authored with another selenographic authority, Patrick Moore, to whom the Visions of the Universe exhibition is dedicated. I found online a reminiscence of Wilkins by an acquaintance describing him as a “proto-Patrick Moore”, but he was perhaps also a direct inspiration. In an obituary of his colleague, Moore wrote of the “prodigious amount of work” that went into the mapping project but, also, that “his personal enthusiasm was inspiring”. Moore felt a “deep sense of personal loss”.

Wilkins did not quite become the media star that Moore did, but he made “numerous broadcasts and television appearances”. You can, for example, see him (his telescope, his map, and his daughter) here in a 1953 Pathé newsreel. Somewhat more infamously, he made the news in 1954 when he announced his observation of “the most extraordinary feature known on the moon today”.

This was a curved shadow, already spotted and described as bridge-like by an American astronomer, John J. O’Neill. It was reported as a 20-mile arch, which can be seen clearly in the photographs reproduced in one of the newspaper reports, viewable at the bottom of the page here. It was, however, no more than a trick of the light, rather like the Face on Mars.

The episode seems to have damaged his credibility considerable and may be one of the reasons that he is less than well-remembered today. Part of the problem was that Wilkins spoke to the press and on the radio before submitting his, rather more cautious, observations to peer scrutiny, His case was not aided by his initially appearing to hint that the structure could be evidence of life on the moon: phrases like “looks artificial” and “almost like an engineering job” led some to leap to such conclusions, even if they were simply descriptive.

The “bridge” was not included in Wilkins’ map, although it did incorporate some other erroneous details. Nevertheless, NASA purchased at least one, and possibly several, copies of the reduced reproduction of his lunar chart when preparing for the Apollo moon landings. His map was also used to help match up the first photographs of the far side of the moon, produced by a Lunar 3 in 1959, with features visible from Earth.

As well as the originals of three editions of the maps themselves, the Museum also received a number of notebooks, all kindly donated by Wilkins’ daughter. The notebooks include formulae, photographs, newspaper cuttings, original drawings and observational notes, from Wilkins’ Kentish observatory and visits to professional observatories in France and the US. They are testament to his years of dedicated work.

When you go (as you must) to see the images, the ingenuity and the leaps that have been made in professional and amateur astronomical imaging on display in the major exhibition, do also remember to pop over to see “the World’s greatest Moon Map”.

Advising government: did Isaac Newton get it wrong?

Cross-posted from The H Word blog.

Just as today, governments past took advice about science. Isaac Newton gave evidence on solving the longitude problem. Was his advice as counter-productive as many have said?

Isaac Newton

There have been a lot of posts lately in the Guardian Science blogs about the role of the new chief scientific adviser, Mark Walport. While finding myself in the novel position of attempting to offer some thoughts to this incoming chief, I have also been co-writing a book about the search for longitude at sea, much of which revolves around issues of the relationships between skill, expertise, government and the public.

It turns out, of course, that advisers to government have often drawn flack, usually from those who stood to lose out financially as a result of their advice. Sometimes, though, that criticism comes as a result of hindsight. Given posterity’s tendency to condescend, that criticism is not always fair.

When the first Longitude Act was passed in 1714, the Walport equivalent was Isaac Newton. Although most often thought of as a solitary genius with apples falling on his head in Lincolnshire or writing an incomprehensible but revolutionary book in Cambridge, Newton was also to be an MP, Master of the Mint, President of the Royal Society and adviser to government.

When parliament considered a petition that asked for rewards to be offered to those who could help solve the problem of finding longitude at sea, Newton’s evidence was very clearly incorporated into the Act as written. As, thereafter, an ex officio Commissioner of Longitude, Newton also became one of those who judged submitted ideas and advised on whether they might be worth supporting.

It has become common to blame Newton for deflecting the commissioners and British government from what has been judged as the “correct” path to a successful outcome. It has been suggested that Newton was naturally biased to favour astronomical solutions and had little time for or interest in clocks as the way forward.

It seems clear that Newton did think that astronomical methods would – at some point – provide a successful solution. He believed that his evidence about their potential accuracy was reflected in the several levels of reward offered in the 1714 Act. In addition, the fact that the Act indicates that a reward might be payable after a single successful trial may show an assumption that the answer would lie in something universally applicable, like astronomy, rather than a machine.

Usually seen as most damning is the fact that Newton stated several times that longitude was not to be found by clockwork. He also suggested that clocks put forward for reward should be examined and trialled by others before the commissioners need meet to consider them.

Such facts have led some to declare that “even Newton could get it wrong”. Such a view has been put forward in histories of longitude and, unsurprisingly, by those writing the biography of John Harrison, whose disputes with the commissioners and well-rewarded sea clocks are well known. However, it has also been stated in Richard S Westfall’s biography of Newton that (p. 837)

His deprecation of clocks may have helped later to delay the acceptance of Harrison’s chronometers [sic], which did in fact offer a practical determination of longitude at sea.

Leaving aside the fact that Harrison’s unique watch left the British public a long way from possessing a practical solution, is it fair to say that Newton was prejudiced against clocks and retarded the putting of government funds into this method? Nope. Not really.

Firstly, Newton was dead right that longitude “is not to be found by Clockwork alone”, so long as astronomical methods were the only way of checking that an on-board clock was behaving itself.* As he said, a clock might be able to keep track of longitude but, should the clock stop or become erratic, only astronomy could help find longitude again. This essentially remained true until wireless radio signals could be used to compare a ship’s local time (determined astronomically) with a broadcast reference time.

Newton was also not so prejudiced against clocks that he did not wish to be bothered by applications from their makers, or at least no more than he was by any other such applications. In the case of astronomical methods, too, he advised that they be examined by other experts before being presented to the commissioners.

We also know that, several years earlier, Newton had been interested in Henry Sully‘s ideas for making a longitude timekeeper – something he went on to do in the 1720s – and had encouraged him, even passing on information about another horological novelty that he had come across.

Newton certainly could be wrong – I am sure that everyone can think of a few examples – but not really about this.

The difference in longitude between two places is equivalent to the difference in local time.

Drawing Mars in Greenwich: recreating an experiment for Stargazing Live

Cross-posted from The H Word blog.

Recreating Mars drawing experiment in Greenwich
Filming for Stargazing Live at Queen’s House in Greenwich. Photograph: Marek Kukula

This week [NB This post was first published on 7 January 2013] sees the return of the BBC’s highly successful Stargazing Live. It starts on Tuesday, in an episode that follows last year’s biggest astronomy story by focusing on Mars.

In thinking about the search for possible life on Mars, the programme will include some of the historical observations and debates that I discussed in a previous post. I’m delighted that the programme gave us at theRoyal Observatory a chance to recreate a key Greenwich contribution to the story.

This was the 1903 experiment carried out by E. Walter Maunder, an assistant at the Observatory, exploring perception at the limits of vision. It was one element in his campaign against the then-dominant view that the Martian surface was covered with immensely long, wide and straight “canals”, thought by many to the work of an advanced civilisation.

Maunder was not alone, being joined by Eugène Michel Antoniadi andWilliam Campbell, together described in Michael J. Crowe’s The Extraterrestrial Life Debate as “the leaders of a wrecking crew” that demolished the Martian canals.

Maunder, with the assistance of the headmaster of the Royal Hospital School in Greenwich, asked a number of the school’s pupils to draw from different depictions of Mars, placed on a board at the front of the room.His results suggested that, particularly at certain distances, the eye tended to resolve indistinct waves and dots into straight lines, suggesting that the “canals” were an optical illusion rather than real surface features.

Ever since I heard about this experiment, I have wanted to recreate it. Asking people to undertake an exercise like this is a wonderful way to understand the problems and contingencies surrounding astronomical observation and recording (imagine not only peering at this small image, but it flickering in an unsteady atmosphere, and having to keep taking your eyes away in order to represent it on paper). I also wondered if it really worked as Maunder described.

Maunder claimed in his paper that the boys, aged around 12 to 14, were all “wholly and entirely ignorant of the appearance of Mars in the telescope, and of the discussions which have taken place as to the markings on his surface.” I have always wondered if this was true, given the widespread popularity of the Martian canal idea at this period.

Our guinea pigs were probably familiar with what Mars looks like when photographed today, but less likely than the 1903 schoolboys to think of drawings or canals. An interesting difference was their age and the fact that most of them were art students. This probably produced different results than had we picked people off the street but might compare interestingly with the naval cadets. The latter were encouraged by Maunder, and probably by their education, simply to draw what they could see. Our art students may have been more likely, despite my instructions, to attempt to interpret the image and to consider different graphic approaches to its re-depiction.

It is likely that the experiment took place in the school’s old gymnasium. This no longer exists, so the BBC team opted for another of the school’s former buildings – the beautiful Queen’s House. They set up the experiment pretty faithfully, with distances and scales as specified in Maunder’s paper. Told to draw, our students obliged, and demonstrated that their eyesight and drawing ability was a good deal keener than mine.

Did our results back Maunder’s? Sort of. I didn’t see the generation of any “canals” where little or nothing appeared on the original image, but there were certainly more straight lines. In our small sample, it also appeared that the middle rows were more likely to see these lines than those nearest (who saw more detail) or those furthest away (who saw little distinctly). It could be argued that these distances mimicked the experience of observing with particular-sized telescopes, creating the conditions where the eye tends to resolve indistinct detail into non-existent straight lines.

Maunder’s report of this experiment apparently brought a key ally to the campaign against Martian canals – the veteran Canadian-American astronomer Simon Newcomb. It was, however, just one of the arguments brought – one of the simplest being the point that if straight canals like those reported by Percival Lowell did exist on the curved surface of Mars, they ought to appear curved to the observer on Earth.

In his writings, Maunder focused on scientific evidence and his own experiences as an astronomical observer. He chose to stay clear of the philosophical and religious dimension of the debate, despite the fact that his popular writings in astronomy were usually framed with natural theology and Biblical references.

Religious beliefs could support either position in the debate about the existence of life on other planets. However, it was clear that Maunder, an active member of a small pentecostal, adventist sect, believed man’s relationship with God and place in the universe were unique. He could not countenance intelligent, canal-building Martians – and thus his scientific arguments were motivated by religious belief.

Watch on Tuesday to see how the experiment went and how it fits into the long history of observing Mars and the search for extra-terrestrial life. Also visit Alien Revolution a small, free exhibition at the Royal Observatory, opening in March.

In the end the section of the film that included the experiment wasn’t run live on Stargazing, due to lack of time. Happily, the whole thing was made available online and you can see it here.

First catch your spider: astronomical arachnids

Cross-posted from The H Word.

Garden spider in web.

Spiders have played a key role in the history of astronomy. This is not simply in being creatures that have kept vigil with the nocturnal astronomer, who is inspired, Robert-the-Bruce-like, by their skill and tenacity, but something far more fundamental.

Spider silk was sufficiently fine, sufficiently uniform and sufficiently strong to be used in the focus of a telescope’s eyepiece for precise measurement. Rather than cross-hairs, astronomers spoke of “wires”, against which the position of a star might be read. Several such spider-silk “wires” or “threads” might help time the transit of a star across the local meridian or, moveable, help measure the distance between binary stars.

Looking the other day for something else, I was pleased to come acrossan 1894 article in the journal of the British Astronomical Association by one of the Royal Observatory’s assistants, E Walter Maunder, that was a how-to guide to “Making a Spider Line Reticule”.

My headline is taken from Maunder, who refers to “Mrs Glasse“, whoseThe Art of Cookery was famously supposed to have instructed readers to “First catch your hare”. In the spirit of the best how-to and make-and-mend housewife, Maunder was sharing his knowledge as money-saving advice for those who could not afford a professionally made filar micrometer. That said, spiders were being caught and used by astronomers at Greenwich for years, and were to be until at least the 1950s.

Unlike Mrs Glasse, Maunder had some hints on animal capture. The spider required was Epeira diadema, “the handsome coronetted spider of our gardens”, although “she has no astronomical monopoly” and an ordinary house spider might do. As he says, “The best time for a raid is the month of October” – until it recently turned cold I spotted many beautiful garden spiders with magnificent webs even in uninspiring urban front gardens.

To catch and keep your spider, she should be “lifted out of her web and placed in a small paper bag, the bag being closed by gently twisting up its mouth. Any number of spiders may be secured and kept ready for use when required if each one is imprisoned in a separate bag.”

Next comes the crucial step, with the acquisition of a “fork”, aka “a piece of wire bent into the shape of a U”, about 12-15 inches long, with the two points about 3 inches apart; “of sufficient width, that is, to well overlap the frame to be webbed, so as to give enough tension to the webs to keep them straight”.

Just previous to winding, the fork should be coated with the usual commercial “brown hard varnish.” The operator then mounts on a stool, so as to give his spider a further drop, places his fork ready to his hand, and taking the paper bag in his left hand, and a small straight piece of wood, gently lifts out the spider. The operator then takes the fork, and when the spider has dropped two or three feet, puts in his fork, and gently winds up, pushing forward the fork as it is rotated, so that the thread lies on it in a zig-zag manner. Other forks may be filled if the spider is in the humour for spinning. If Arachne is inclined, however, to be obstinate, gently blow on her with a full steady breath…

The filled forks were to be placed vertically for about an hour, after which time it was possible to pack them away in boxes until required.

Maunder’s article then carefully describes the process of fitting the threads to a frame, and fixing them at a proper tension with some more varnish – applied, he suggests, with another unlikely astronomical instrument: a knitting needle.

Of such things – and sealing wax and string – are the most distinguished careers made.

Is there ‘a rising tide of irrationality’?

Cross-posted from The H Word.

Painting of a comet over sea by Herbert Barnard John Everett

I often come across the assumption, or assertion, that pseudoscientific views or belief in the paranormal are increasing. Yet the claim that there is a “rising tide of irrationality” seems to be backed by little evidence.

The “rising tide” comment is taken from a tweet by Daniel Loxton, editor of Junior Skeptic magazine, who also recently tweeted:

I keep hammering on point that paranormal claims and attempts to get to bottom of them have always been with us, and always will be with us… 15 Nov 12

This certainly chimes with my view as an historian. Loxton also pointed me to a piece on the data collected since 1990 by Gallup that indicates “the public’s persistent belief in the paranormal”. While particular types of paranormal interest come in and out of fashion, overall it seems that views considered non-, anti- or pseudo-scientific have a fairly static presence.

So why the assertion that it is increasing? Perhaps today we can point to the potential for visibility and collective presence generated by the internet. There are also new ways in which unscientific views have entered the political arena, making them more visible and problematic – something recently discussed by Erik M. Conway and Naomi Oreskes inWhy Conservatives Turned Against Science.

But these factors don’t account for the perennial sense of a rising tide. Perhaps it is simply that the more sensitive to or aware of something you are, the more you keep on noticing it. In this case, much of the sensitivity is due to the fact that elements of what is branded pseudoscience can be deeply entangled and competitive with perceptions of orthodox science. (It’s worth having a look at Steven Shapin’s recent review of Michael Gordin’s The Pseudoscience Wars on the origins of the term.)

Take astrology, for example. It was once intimately connected with astronomy. The words were more or less interchangeable in the early modern period, although for simplicity we can characterise astrology as having been one of the most significant drivers for accurate positional astronomy, alongside timekeeping, surveying and navigation. By the end of the 17th century, for elite astronomers, this connection was disintegrating and, although their data continued to be used by astrologers, the borders between legitimate and non-legitimate uses of astronomy were redefined.

The astrologers did not go away, and popular belief in the effect of heavenly bodies on the mundane world – on individuals, nations, crops, weather or health – certainly remained throughout the 18th century and beyond. A market for astrological publications and symbolism continued to exist, even if it was not until the late 19th century that there was a notable revival of interest in astrology and other things esoteric and spiritual among more fashionable and educated audiences.

One place in which we can trace this ever-present undercurrent of astrological belief is, of all places, in the archive of the Royal Observatory in Greenwich (now held at Cambridge University Library), where a quick search of the online catalogue reveals that Astronomers Royal throughout the 19th and 20th century had to deal with enquiries from the public relating to astrology. Undoubtedly there was such correspondence in the 18th century too, it simply was not kept as diligently.

Astrological enquiries of the mid 19th century – before the revivals of either late 19th-century esotericism or the 20th-century’s New Age – were also referred to in a published account. This was The Midnight Sky, written by one of the Observatory’s assistant astronomers, Edwin Dunkin.

In the second edition, Dunkin described the work of the Royal Observatory, where he had been based since 1838, and noted that,

there is one class of correspondence which, during the author’s long connection with it, he has never known to fail, and which should be alluded to here, to show that, even in this the nineteenth century, there are paradoxers of all kinds, both scientific and social, who call upon the astronomer for advice under difficulties. For it must be acknowledged that the Greenwich astronomer, in addition to his stated public duties, is also very generally supposed to devote some attention to astrology…

He went on to describe “individuals calling frequently at the Observatory gate, requesting information about their future destiny”, letters “enclosing Post-Office orders, requesting a nativity cast in return”, and how “On one occasion, a well-dressed young woman, apparently in great distress, called at the author’s private residence” asking for information about an uncle at sea. “She left in tears, because she was informed that the stars were unable to satisfy her wishes.”

Dunkin’s “final example of the march of intellect in the nineteenth century” was a letter received more than 30 years before: “I have been informed that there are persons at this Observatory who will, by my inclosing a remittance and the time of my birth, give me to understand who is to be my wife. An early answer, stating all relative particulars, will greatly oblige”.

Astrological questions, or ones on Mayan prophecy or UFOs, still come to places like the Royal Observatory. We can at least comfort ourselves with the knowledge that this puts us in esteemed company, and that ’twas always thus, and ’twill ever be.