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.



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”.

Picturing science: sharing knowledge, selling ideas

William Huggins' depiction of the solar surface. Source: National Maritime Museum
William Huggins’ depiction of the solar surface (National Maritime Museum)

This image looks like a curving, curling, abstract mosaic. It is, in fact, an attempt to capture what one observer saw when he looked through a filtered telescope lens at the Sun’s surface. Before photography developed, if astronomers wanted to share their visual experience they could only do it by drawing, adding an ability with pencil to the many necessary accomplishments of the observer. Photographing detail on the bright Sun was to prove a particular challenge.

When you know what it is you should be looking for, it is much easier to see. Familiar as we are today with spectacular images of the Sun in all kinds of different wavelengths, we have come to expect pattern, difference, structure, feathery and filament-like shapes and vast bursts of gases. This was unknown before telescopes could supply sufficient magnification and resolution.

Careful drawings were backed by verbal descriptions, but it was only by looking for themselves that other astronomers might come to accept your interpretation. Was the surface pattern “feathered”, “granulated”, “rice-grain”, “slashed straws” or “willow-leaf”? These were all terms used by observers like William HugginsSamuel Pierpont Langley and James Nasmyth, who revealed that the Sun was not the anticipated smooth, bright disc, punctured only by a few sunspots.

These images tell two stories. One is about the astronomers who looked at, tried to capture and explain the nature of the solar surface. The other is about sharing those images, knowledge and possible explanations with a wider public. These solar close-ups were published in scientific papers, but I have taken them from a set of 38 lantern slides, produced toillustrate lectures on the Sun by a company called York & Son in around 1880.

Drawing of sunspots by James Nasmyth (National Maritime Museum)
Drawing of sunspots by James Nasmyth (National Maritime Museum)

The set includes images that show observational instruments, experimental or demonstration equipment and diagrams to explain possible theories of solar activity. The slides allowed the lecturer to, for example, introduce the audience to competing explanations of the appearance of sunspots. William Herschel had suggested that they were openings in the Sun’s luminous atmosphere, revealing a cooler surface beneath; Alexander Wilson considered them depressions in the solar surface.

Experiment for using a prism to split sunlight (National Maritime Museum)
Experiment using a prism to split sunlight (National Maritime Museum)

I don’t know how many of this set of slides were produced, nor whether any of them were used to enliven one or more actual lectures on the Sun (apart from my own). If they did, the part on sunspots and the solar surface might have run similarly to this 1872 article in the Popular Science Monthly, by the editor Edward Livingston Youmans. While sunspots had, of course, been long known, their complex structure was newly revealed:

But, when a telescope of high magnifying power is directed to the sun, its aspect is greatly changed: the spots lose their simplicity, and the photosphere its uniformity, and in both there are a revelation of structure, a diversity of parts, and a variety of changes, which at once provoke questions in the mind of the observer, as to the causes of this diversified appearance, and the constitution of the body which presents them. The hypotheses put forth are ingenious; but, while the facts of observation are rapidly increasing, and there is a growing agreement on many points, there is still profound uncertainty as to the interpretation to be given to the leading phenomena.

An article or a lecture on the Sun, presented in the last quarter of the 19th century would have introduced its audience to a whole new vocabulary of penumbra, faculae and photosphere. It would also have focused on the use of novel techniques in astronomy, above all the photography and spectroscopy that opened the way to a whole new branch of science. It also introduced the idea that surface irregularities on the Sun might be linked to magnetic activity and terrestrial climate.

It was an exciting topic for a lecture around 1880 – something that a commercial producer of visual aids probably rightly took up as an opportunity.

Messing with time

Cross-posted from The H Word blog, first posted on 31 March 2013, the first day of British Summer Time.

Analogue clock

It’s hardly surprising that I’ve become very aware of time and how we measure it since beginning work at the Royal Observatory Greenwich. What has really struck me is how much we, on the one hand, are resentful at any suggestion that we alter the way we measure time and, on the other, have done just that many times over the course of history.

Although it’s useful publicity for the Observatory, I never cease to be amazed that the change of the clocks, which happens twice a year ever year like … err… clockwork, is always a news story. Suggestions that we might do away with British Summer Time, or shift to what is euphemistically called Double Summer Time (aka Central European Time) are huge debating points. The fact that we do, or the fact that we might cease to, add leap seconds are stories that both receive many column inches.

Although the introduction of BST was a very 1900s notion of making better – that is, more healthful and productive – use of our long summer days*, history suggests that it takes something like a world war to implement such seemingly radical changes. There is often a sense that diverting from whatever it is we are used to is, somehow, unnatural. It certainly seems unnatural when we are ripped untimely from our beds but, even before the arrival of this annual ritual, there was nothing natural about the way we measured time.

Take GMT, which traditionalists are keen to defend by rejecting summer time and by adding leap seconds to ensure that we do not drift too far from having the midday sun above the meridian at Greenwich at noon. In the scheme of things, it is almost as much of a novelty as BST. It only became official standard time in Britain in 1880, even if it had been used in specific contexts, like railway timetables or in navigation, some time before. Its use as a standard to which international time zones are aligned was a matter of slow adoption from the late 19th century onward.

The implementation of a national standard time, which might be some 20 minutes different from your local time, should you live in the west of the country, was seen by some as an unnecessary novelty. There were those who made a stand, and even today the chimes at Christ Church in Oxford still stick to local time. As can be imagined, the idea being floated at the end of the 19th century that there might be a universally-adopted International Time was much mocked, resented or worried about.

But the national or local times that seemed more meaningful to people are, of course, also artificial products. They are expressed as mean time, which is an averaging out of Sun’s the apparent motion that was adopted in deference to the introduction of a new technology – the clock. Clock time is produced by an artificial system that imperfectly mimics “real” time, which is a product of the Earth’s daily rotation and annual orbit.

The difference between mean time and “real” or apparent time is expressed by what’s called the Equation of Time. This was first calculated in the second half of the 17th century, when the introduction of pendulum clocks made the business of artificial timekeeping sufficiently precise. The fact is, the Sun is rarely at its highest point over the Greenwich meridian at the moment our watches show noon.

Things get even more complex when we start looking into how calendars have been calculated and established. These are fascinating histories that are intertwined with everything from the story of astronomy to how we live and order our lives. Our time has been messed with for centuries and it is not, forgive the pun, a clock that can be turned back.

* Personal gripe: many people seem to think that putting the clocks back in Winter is “daylight saving” and is designed, somehow, to give us more daylight. Guys: “daylight saving” is used in Summer and nothing, but nothing, will create more daylight in Winter.

Book review: Venus Seen on the Sun

This review was first published in the British Journal for the History of Science 46 (March 2013)

Jeremiah Horrocks and Wilbur Applebaum (trans.), Venus Seen on the Sun: The First Observation of a Transit of Venus by Jeremiah Horrocks. Leiden: Brill, 2012. Pp. xxiv +82. ISBN 978­90­04­22193­2. €99.00 (hardback). 

Jeremiah Horrocks' observation of the 1639 transit of Venus, as published by Johannes Hevelius with Horrocks' Venus in sole visa in 1662.
Jeremiah Horrocks’ observation of the 1639 transit of Venus, from Johannes Hevelius’ version of Venus in sole visa (1662).

The June 2012 transit of Venus was the occasion to turn our attention once again to the observers of the previous transits, in 1639, 1761, 1769, 1874 and 1882. Thus it is that we have the first English translation since the nineteenth century of Jeremiah Horrocks’s account of his 1639 observation. This seems long overdue, especially given the fact that the only other available translation, which is ‘more free in style than necessary’ (p. xxii), was produced by someone who lacked familiarity with the history of astronomy and introduced a number of errors.

The text of Venus in Sole visa, first published by Johannes Hevelius in 1662, is not only an account of the first observation of this rare event but also a fascinating commentary on astronomy at a period of significant change. The transit gave Horrocks the opportunity to judge and correct the work of Copernicus, Lansberge, Longomontanus and Kepler, with the Rudolphine Tables of the last being proved much the superior. It was this, rather than the observation itself, or even its indication of the planets’ great distance and lack of luminosity, that marked the significance of the work. In addition, the text is remarkably readable: as Applebaum writes in the brief introduction, ‘It is filled with an unrestrained enthusiasm and intensity of commitment from which a youthful and refreshing naiveté is never wholly lacking’ (p. xxiii).

Short though the introduction is, it helpfully outlines Horrocks’s life, the history of the four draft manuscripts of the treatise, and the astronomical context in which it was produced and read. Applebaum’s notes in the main text are full and extremely helpful, in technical matters and in relation to the books and manuscripts that Horrocks was referring to, both scientific and literary. I cannot comment on the faithfulness of the translation but it reads well, with the exception, perhaps, of Horrocks’s poetry, which has been translated for meaning rather than scansion.

A sense of Horrocks’s personality arises from the text, in part due to his adhering to ‘a style now completely gone from scientific literature’ (p. xxiv). There is infectious zeal, leading to amusingly damning judgements, as well as the poetry, digressions and classical allusions. (The transit of Venus is a subject for which coy personifications and metaphors of seduction seem not yet to have gone out of style.) It is not hard to see why successive readers of Horrocks have taken him to their hearts. The Victorians, with Arundell B. Whatton’s 1859 Memoir and a series of essentially fictional memorials and portraits, naturally led the way, bequeathing their vision of a pious and persevering young cleric, fighting ill health to perform first his Christian and then his scientific duty.

Jeremiah Horrocks' observation of the transit of Venus, as imagined in 1891 by Eyre Crowe
Jeremiah Horrocks’ observation of the transit of Venus, as imagined in 1891 by Eyre Crowe

We, no less enthused by a local hero with his finger on the pulse of Continental astronomy, will still rejoice in the account of a young astronomer’s greatest moment. Although touched by the thought of his work being cut short by tragically early death, Horrocks nevertheless comes across as wonderfully vital. The modern, positively reclaimed term ‘geek’ comes to mind in reading Horrocks’s description of astronomers who ‘immoderately delight in trifling things, which do not move others in the least’ (p. 16). Something similar arises from his lauding of Kepler, ‘the unparalleled prince of true astronomy’ (p. 51), and his dismissal of the ‘boasts’ and ‘impotent clamour’ (p. 72) of Philippe van Lansberge and those who relied on his tables.

Apart from Kepler, Horrocks’s greatest praise is for ‘the recent and wonderful invention of the telescope’ (p. 8). Despite writing three decades after the instrument was patented, Horrocks clearly felt that ‘the Belgian telescope’ still required a better reputation, and thus he affirmed the increased accuracy it allowed and defended it against those who suggested it could create illusions. It is eulogized in verse, as readers are urged to ‘learn the wonders of such a great tube’ (p. 11) and join him, lying in wait to spy Venus.

Being a review of a book published by Brill, this must end with the inevitable comment about cost. Ninety-nine euros for just over a hundred pages is steep by any measure. Given the accessible style of Horrocks’s writing and Applebaum’s translation, it is a shame that this should simply be a library-based reference work. The author’s preface promises a full-length biography of Horrocks in the near future. It is much to be hoped that this does indeed appear, and that it is available at a price that places it within reach of significantly more pockets.

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.

The tale of a telescope

In this month’s Journal for the History of Astronomy I have a book review of Richard Gillespie’s The Great Melbourne Telescope – a book I enjoyed reading and a review I enjoyed writing.

The Great Melbourne Telescope. Richard Gillespie (Museum Victoria Publishing, Melbourne, 2011). Pp. 188. AUD 29.95 (paperback). ISBN 978-1-92183-305-2.

This readable and well-illustrated book takes a journey that begins in 1840s Ireland and passes through the astronomical élites of Victorian Britain, colonial Australian society and twentieth-century international collaborative research programmes. The telescope that provides the focus of this story is both a remarkable physical pres- ence and an object of different meanings in the minds of those who dreamed it up, designed it, built it, worked with it or simply visited it. The cast of characters who swiftly cross these pages include British princes, a Fenian agitator, colonial officials and, of course, astronomers major and minor.

Gillespie commendably handles this broad canvas and the specific or more technical details. The content, bibliography and endnotes are proof of knowledge and research that is woven well into an engaging narrative, only occasionally weighted down with the detail necessary to explain the frequent delays and pauses that characterized the history of this telescope. Each chapter opens with a section of semi-dramatized storytelling that, although it felt a little artificial with repetition, works to keep the reader’s interest and, more importantly, to focus attention on telling episodes.

Thus the first chapter opens on a cold night in Ireland, with Lord Rosse, Sir James South and Thomas Romney Robinson observing with Rosse’s ‘Leviathan’. These men, the ambitious telescope and the aim of resolving disputes about the nature of nebulae form the story’s background. The southern hemisphere beckoned as a field that, despite John Herschel’s work, remained relatively unexplored, and with climates more promising than Ireland’s for the use of large mirrored telescopes. Rosse and Robinson, while President of the Royal Society and the British Association for the Advancement of Science respectively, had their moment in 1852 to create the joint Southern Telescope Committee.

The published correspondence of this committee presents the historian with a wonderful resource to explore the currents of astronomical research, telescope design, politics and personalities. Disagreements caused delay as did, almost fatally to the project, the Crimean War. It took intense lobbying from the colonies to revive the project, and so enters, in the second chapter, the bounding figure of William Wilson, an ambitious, undiplomatic professor of mathematics in Melbourne. Gillespie’s account of society in colonial Victoria is particularly well drawn, with a sense of its burgeoning development until depression hit late in the century. It is a place where names and fortunes could be made, where local, colonial and national identities were consciously developed, and where a large telescope could make a big statement.

The following two chapters open with the drama of casting the telescope’s mirror at Thomas Grubb’s Dublin workshop, and with the Melbourne Observatory’s director, Robert Ellery, writing to explain the difficulties encountered working the telescope at a distance from British and Irish expertise. Not until chap. 5 and the 1870s do we see “The telescope at work” in a regular, satisfying manner, although problems remained in finding observers, keeping the mirrors untarnished and producing results that would justify the costs. As described in the following chapter, however, justification was also found in telescope’s symbolic role within Melbourne and beyond. From the beginning, monthly open evenings were held, and the telescope’s educative, or public relations, role as “the city’s scientific icon” (p. 119) should not be underestimated.

The affection felt for this instrument explains its final chapter. While economic slowdown and changing priorities meant that it was largely unused in the first half of the twentieth century, its symbolic importance, along with claims of economy, let to its post-war “Rebirth”. Twice it was completely remodelled, with increasingly automated operation and a new mirror collecting light for analysis by a host of instru- ments. Where once the observer tackled the telescope manually, trained his eye to see and interpret the faint light of nebulae, and recorded his impressions in drawing and lithograph, now the Great Melbourne Telescope’s light was analysed by computer in the search for evidence of dark matter.

This new life was ended by a bushfire in 2003. This disaster has, however, given Victoria’s Museum and Astronomical Society the opportunity to reunite the original Grubb axes and bearings with parts of the telescope long-since removed. Because of the desire to use the instrument for public observing sessions, it will be fitted with new mirrors and finding system, creating a curious hybrid, like most of our working historical telescopes. While astronomical research continues onward to ever-larger reflectors, this instrument will play its old role of engaging the public with astronomy. And as Richard Gillespie’s enjoyable book makes clear, it should also lead visitors to consider Australia’s astronomical heritage, tied closely as it is to the history of the nation itself. The telescope’s story is one worth telling.

Tartu: “the Russian Empire’s leading observatory”

The following is a book review that I did for the Journal for the History of Astronomy. It appeared in the February 2012 issue (£).

Tartu Tähetorn/ Tartu Old Observatory. Lea Leppick (Aasta Taamat OÜ, Tallinn, 2011). Pp. 215. €30. ISBN 978-9949-9018-3-8.

This volume marks the 200th anniversary of the Tartu Observatory. In dual text – Estonian and English – and with many full-page illustrations, it is a handsome and weighty volume that covers the 200-year history of the Observatory in a series of chapters and sub-sections by a number of different authors. The editor, and lead author, Lea Leppick, is an expert on the history of Tartu University, of which the Observatory was a part for much of its history. Leppick declares in the introduction that “This volume has been written by an historian, not an astronomer, as can be seen by the approach to the material”. However, while this may be true of some sections of the book, other contributors have added detail on the “scientific background” (p. 7) and more recent history of the institution, meaning that there is a somewhat disjointed and uneven feel to the whole.

A focus on Tartu Observatory is an opportunity to discuss a number of important themes and events in the history of science, but it is also potentially difficult to write as a celebration and without a strong narrative. One of the difficulties is that while under the directorship of Friedrich Struve, from 1820 to 1839, Tartu could be described as the “Russian Empire’s Leading Observatory” (p. 39), it was afterward essentially a provincial institution that, until the arrival of Ernst Öpik century later, had limited international communication. It had one really admirable instrument, the 1824 Frauhofer refractor, but, for much of its history, little in the way of significant publications. While there is some detail on the various directors, their teaching and writing, it is difficult to get a sense of what those who financed the Observatory really felt it was for and how its role developed over time. While a plethora of projects and related institutions are mentioned, the lack of an analytical overview or even a timeline is sorely felt.

Naturally, the complexity relates to wider historical events. There is a fascinating book to be written on astronomy in Estonia, reflecting successive periods of war, revolution and peace under Sweden, Imperial Russia, German occupation, the USSR and independence. Several tantalising but undeveloped leads arise. While Struve’s measurement of a meridian arc had clear importance for national prestige and political and military control, attracting support and interest from the Russian imperial government and military, it is claimed here as “purely scientific” (p. 43). Likewise, support of “basic research” (p. 111) is taken as a given but deserves greater scrutiny. The interest of several directors in popular science writing is mentioned, but the content and aims of their work deserve more attention. It is fascinating to learn about the role of textbooks, popularisations and museum displays in, for example, the creation of Estonian scientific terminology after 1919, or in response to the Soviet emphasis on astronomy in the 1950s, but more of this, and an accompanying reflexivity in the discussion of the Tartu’s latest incarnation as a science centre and museum, would have been welcomed.

The strength of the book is the many images included, not only of buildings and directors, but contemporary publications, manuscripts, plans, instruments and photographs from a range of sources. However, parts of the text are shaped around these images, making the book more like an exhibition than a history. It is made up of a series of short sections, which sometimes take the reader some distance from the story of the observatory and involve leaps in chronology and a lack of coherence. It is sometimes unclear who the book is aimed at: the level of detail in some sections, whether scientific or institutional, often seems too dense, indeed condensed, for a non-specialist to penetrate, and yet the treatment of each topic is too brief to satisfy academics. Toward the end, when the text is peppered with “we”, “us” and “our”, there is a sense that this is a book produced by and for those associated with the Observatory and university.

There are, unfortunately, a number of errors in the text. Some are translation issues, for example, “passage instrument” appearing for “transit instrument” and “mirror telescope” for “reflecting telescope”, but others are more basic. It is claimed that Uranus “was found in the exact location predicted”, as “a brilliant proof of … theory” (p. 24), or that time zones were initiated at the 1884 Meridian Conference (p. 117). Nevertheless, the book does usefully bring the history of Tartu Observatory, and aspects of Estonian university education and science, to English-speaking audiences, making use of source material in Estonian, Russian and German. The 2005 inscription of the Struve Geodetic Arc as a World Heritage site and the 2011 opening of a museum in the restored Observatory are indicative of ambitions for international recognition and, we hope, the start of yet another chapter of this 200-year-old institution.

Preparing for the transit

I have recently been working on a small display at the Royal Observatory (opening next month) called Measuring the Universe. Despite being small-scale the topic is – in every sense – vast. We are trying to cover the history of measurements of the scale of the solar system, the distance to the nearest stars, the space between galaxies and to the Cosmic Microwave Background. This takes us from the Earth to the edge of the known universe, and from Greeks to researchers today. [Read more]