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Armagh Observatory

  

1. The First Years

The little cathedral city of Armagh is one of the most famous places in all Ireland. It is not large; its population is a mere 10,000 or so, but it has a long and honoured history. It lies some forty miles inland from Belfast, and with its narrow streets, its two cathedrals and its generally peaceful atmosphere, it has a charm all its own.

It was a place of some importance from very early times, and is said to derive its name of Ard Macha, or Hill of Macha, from an ancient queen, one of three bearing that name said to be buried on the hill now crowned by the old cathedral. In 352 B.C., a later Queen Macha founded the fortress Emhuin Macha, latinized Emania, the place now being known as Navan Fort near Armagh. The seat of the kings and queens of Ulster, it lasted for 700 years and was destroyed in the fourth century A.D. About one hundred years later, the foundation of Armagh as a town followed the arrival of St. Patrick; Daire, the chieftain of the district, provided a site for a church, which was duly built in roughly the position now covered by the Bank of Ireland and its gardens. Apparently, an important synod was held at Armagh in or about 448, and it is also reported that Armagh was a renowned seat of learning in the Dark Ages. Astronomy may well have been taught there.

Yet Armagh has suffered more than its fair share of disasters during Ireland's troubled history. Accidental fires destroyed it in 617 and again in 670 ; tribal warfare, the Danish invasions and the various English wars took heavy toll of it. The Bishops of Armagh retired to Drogheda, and in medieval times Armagh sank into what the 1909 edition of the Encyclopedia Britannica described graphically as "an insignificant collection of cabins, with a dilapidated cathedral covered with shingles ". This picture may well have been too gloomy, but there can be no doubt that Armagh had fallen upon evil times. The man who did much to restore it was Lord Rokeby, better remembered as Archbishop Robinson, Primate of all Ireland. And it was Primate Robinson, too, who founded the astronomical observatory which has contributed so much to science.

Archbishop Richard Robinson

Richard Robinson was translated from the See of Kildare to the Archbishopric of Armagh in 1765. He was a man of strong character and immense energy, and financially he was well off, so that he could make his presence felt in no uncertain manner. He was a great benefactor of Armagh; for instance, in 1778 he founded and endowed the city's Public Library, in 1773 he laid the foundation of the Royal School (which is still, to-day, in a highly flourishing condition), and in the following year he was associated with the establishment of the County Infirmary. Slightly less generally popular, perhaps, was his gift of land in 1780 for the site of a new prison. The prison was duly built, and may be seen at the southern end of Armagh's attractive green Mall; aesthetically it is far from unpleasing. History records, however, that the Primate's various schemes aroused the wrath of the celebrated reformer John Wesley, who accused him of being more interested in buildings than in the care of souls! 1

Archbishop Robinson was anxious to found an Ulster University. This was by no means a new idea; earlier attempts had been made during Queen Elizabeth's reign, first by Archbishop Dowdall in 1558 and then by the Earl of Tyrone in 1599, but neither had achieved any result, and in fact Robinson was destined to be equally unsuccessful. Yet he tackled the problem with his usual energy, and it is probable that the foundation of the astronomical observatory was part of a larger plan.2 Very probably, too, the Primate's interest had been aroused when he had met the great astronomer William Herschel at the health-resort at Bath.

An important early step was to find a director for the proposed Observatory, and fortunately there happened to be a local man whose qualifications were ideal. This was the Rev. James Archibald Hamilton, who had made his mark as a skillful observer, and had formerly used a private observatory near Cookstown in County Tyrone.

Hamilton was willing to accept the post, and Primate Robinson wasted no time. The construction of the Observatory buildings began in 1789, upon plans drawn up by the celebrated architect Francis Johnston, a native of Armagh who became known in later years as "the Wren of Ireland". The start of the building was commemorated in a bronze medal struck by Mossop, the Irish medallist, duly inscribed: "The Heavens Declare the Glory of God ", an avowal which still appears in the Seal of the Observatory. Hamilton's official appointment was made in the late summer of 1790, and on April 5, 1791, the Primate handed over the management of the institution to a board of Governors and Guardians, made up chiefly of members of the Chapter of Armagh Cathedral. As an endowment for the resident astronomer, the Primate gave the townland of Derrynaught in County Armagh, and within a few months the whole procedure had been sanctioned and approved by the Irish Parliament. It may be interesting to record here the names of those who attended the first meeting of the "Governors and Guardians of the Public Library of Armagh", held on 24 August 1790 to appoint Hamilton as Director. The Primate himself was not present, but the list, as given in the Observatory's manuscript Minute Book, is as follows: Hugh Hamilton, Dean of Armagh (no relation to the Director-elect); Richard Allott, Precentor of Armagh; William Lodge, Chancellor of Armagh Cathedral; the Hon. Percy Jocelyn, who became Treasurer of Armagh Cathedral when the new director relinquished this office; John Friend, Archdeacon of Armagh; John Jones, Prebendary of Mullabrack (who died two months later, and who may not have attended the meeting in person); Henry Leslie, Prebendary of Ballymore and Canon of St. Patrick's, Armagh; Thomas Quin, Prebendary of Loughgall; and, of course, the Rev. James Hamilton himself.

In passing, let us note that the 1790 Act provided for a Director who might prove what was termed "obstinate", and one paragraph from the Act is worth quoting: it stated that the Governors and Archbishop "shall have power and be authorised to meet together and remove the said Astronomer off and from the said Office of employment, and to take from him the income, profits and lodgings to the said Office belonging, from the time of his continuing and being declared obstinate as aforesaid". It seems somewhat doubtful, whether this particular section of the Act will ever be needed!

So far, so good. The Primate had established the Observatory, and presented it with twenty acres of land, together with the estate of Derrynaught (which, it may be added, he had bought with his own money) and various other benefits, such as the lease of the rectorial tithes of the parish of Carlingford. But an observatory cannot function without equipment, and the Primate ordered some instruments as well. The initial outlook was bright, but before continuing with the sequence of events - which sometimes revealed unexpected twists! - it may be useful to say something about the state of astronomical science in 1790.

When making a comparison between the past and the present, one's instinctive reaction is one of surprise that so much has been accomplished in less than two centuries. Modern astronomy is a highly technical science, needing complex equipment. Large telescopes, with their tremendous light- gathering power, can obtain information from galaxies thousands of millions of light-years away; photography and spectroscopy are essential aids (in fact, almost all astrophysical work is carried out photographically), and during the past few decades radio astronomy, radar methods and rocketry have also come to the fore. Nowadays, the astronomer can spend as much time as he likes in examining the spectrum of a faint galaxy far away in space - or, if his interests lie nearer home, study close-range photographs of the Moon or Mars as obtained from space-probes.

Things were very different in 1790. In particular, there were no telescopes even remotely comparable with those of to-day. The largest was a reflector with a 49-inch mirror and a focal length of 40 feet, made and used by William Herschel, the Hanoverian musician who came to England and became famous when he discovered the planet Uranus in 1781. Herschel's "forty-foot" was completed in 1789, and was of good quality for its time, despite its speculum-metal mirror and the fact that it was clumsy and awkward to use; yet even so, neither it nor any other contemporary instruments would be regarded as serviceable in a modern observatory. Moreover, nobody except Herschel seemed at the time to be capable of making optics of such calibre, and refinements such as clock~drives lay in the future.

Herschel was a pioneer in every sense of the word. Though he is best remembered for his discovery of Uranus, much his best work was in the field of stellar astronomy; he was one of the first astronomers to feel that the stars were worth studying in themselves, and he also drew up a picture of the star-system or Galaxy which was basically correct even though some of its details were wrong. (In particular, Herschel regarded the Sun as lying near the centre of the Galaxy instead of well out toward the edge.) In 1790 very little was known about the stars; Herschel spent a lifetime in studying them, and to list all his discoveries would take many pages. For instance. it was he who established the existence of binary systems, a discovery made during his unsuccessful attempts to measure the distances of the stars. He also commented upon variable stars, of which less than half a dozen were then known-whereas to-day there are some 25,000 known variables in our Galaxy alone.

Even more crippling than the lack of telescopic power was the fact that photography and spectroscopy were still unknown. The first studies of the Sun's spectrum were made in the early 19th century, but were not properly interpreted until much later, while it was only about one hundred years ago that astronomical photography first became scientifically valuable. (Incidentally, the word "photography" was first coined by an astronomer - Sir John Herschel, son of William - an interesting historical point which is sometimes forgotten.)

Basically, the astronomer of 1790 could do little more than look through his telescopes, measure the apparent positions of the various bodies in the sky, examine objects such as star-clusters and nebulae, and draw what details he could on the Moon and planets. However, at least the Sun was known to be a star, while the Earth had been firmly relegated to its proper status of an insignificant planet; though stellar distances remained unknown until 1838, Herschel and his contemporaries knew that the stars must be extremely remote. The scale of the Solar System had been drawn up with fair accuracy, and the distance between the Sun and the Earth was usually put at between 80 and 90 million miles, which is only a slight under-estimate. More important still, perhaps. star-catalogues had been drawn up. The oldest observatory in the United Kingdom, that at Greenwich, was founded in 1675 by order of Charles II so that a more accurate catalogue of stars could be produced for the benefit of British seamen,* and this catalogue had been duly produced, thanks to the patient labours of the first Astronomer Royal, John Flamsteed. Under the circumstances, it was remarkably good.

On the debit side, nothing whatsoever was known about the composition of the stars, or about the past history of the universe. Indeed, it was a former Archbishop of Armagh, Ussher, who had stated (during the seventeenth century) that the Earth had been created at a definite moment in October, B.C. 4004. Ussher's method was to add up the ages of the patriarchs and make some other equally peculiar calculations. The final result satisfied him completely, and met with wide acceptance at the time; before long his figure for the age of the world was challenged on scientific grounds, but no astronomer would have dared to maintain that the Earth could be as much as a thousand million years old, whereas the modern figure is around 4,700 million years.

It is worth noting, too, that even leading authorities held views about "other men" which sound strange to our ears. Herschel, by common consent the greatest astronomer of the day, was convinced that there must be intelligent beings on the Moon, the planets, and even inside the Sun; not everyone agreed with him, but he never wavered in his views, and remained faithful to them up to his death in 1822. And in a well-known book on popular astronomy written by James Ferguson, who began life as a shepherd-boy and ended it as a leading scientific writer, we find a section headed "It is highly probable that all the planets are inhabited", which summed up the general opinion at the time. In the edition of Ferguson's book published in 1790, when Armagh Observatory was being completed, there is even a discussion about the habitability of comets. Ferguson writes 3: that "when we consider the infinite power and goodness of the Deity. . . it seems highly probable that such numerous and large masses of durable matter as the Comets are, however unlike they be to our Earth, are not destitute of beings capable of contemplating with wonder, and acknowledging with gratitude, the wisdom, symmetry and beauty of the Creation". This strikes one as being naive, though it must be borne in mind that modern flying saucer enthusiasts and their kind are equally credulous.

Lacking cameras, spectroscopes, radio equipment or rocket launching facilities, an eighteenth-century observatory was therefore confined largely to what is generally termed positional astronomy. Greenwich had established its reputation; by 1790 it was already regarded as the timekeeping centre of the world. The same sort of work was planned for Armagh, since Flamsteed's star-catalogue was already more than half a century old, and instruments had been considerably improved in the meantime. Moreover, Flamsteed had had to work under serious difficulties when he had become astronomer at Greenwich in 1675, since King Charles' generosity did not extend to the provision of instruments; Flamsteed was expected to obtain these for himself. Hamilton, on assuming his duties at Armagh in 1790, was entitled to expect far better treatment, and his ability and enthusiasm could not be questioned.

Actually, our knowledge of Hamilton is limited mainly to his official posts and the brief outline of his life. He was born in 1748, son of Colonel Gustavus Hamilton of Summerseat in County Meath. He entered Trinity College on 1 November 1764, graduating in 1769; for some years following 1776 he lived at Cookstown, where he Set up a private observatory. On 1 March 1784 he became Treasurer of Armagh Cathedral, an office which he held until he went to the Observatory, and on July 13 of the same year he graduated B.D. and D.D. at the University of Dublin. By now he had been transferred to the living of Mullabrack, about six miles from Armagh, but he naturally went to live at the Observatory when he became astronomer there. He was Archdeacon of Ross from 1790 to 1804, when he became Dean of Cloyne; By the standards of his time he was well off financially; it is said that he travelled around in the comfort of a coach and four, and that he subsequently adopted the practice of spending the summers at Mullabrack (where he had installed two curates to attend to local church duties) and the winters at Armagh. His home life appears to have been happy. In addition to his daughter Julia he had two wards, Catherine and Juliana Tisdall, who, it is said, frequently entertained their young suitors in the Observatory dome!1

Primate Robinson was anything but niggardly. The dwelling-house which he provided was both large and pleasant; lying in attractive surroundings, and made of the famed "Armagh marble", it still retains its dignity and comfort to-day (though naturally it has been extended and modernized). A dome was erected, and a transit-room to the east. The outlook for the Observatory was bright, but the situation changed suddenly for the worse when the Primate died, on 10 October 1794. His successor seems to have been profoundly uninterested in astronomy, and Primate Robinson's heirs were clearly un-cooperative, since they countermanded the orders which had been placed for the Observatory instruments. Fortunately they were unable to stop the main piece of equipment, an equatorial by the celebrated instrument-maker Troughton, and three clocks were also obtained - two of them by Thomas Earnshaw of London. One of these (incidentally, the first that Earnshaw ever made) was particularly good. Earnshaw, a famous watchmaker, had claimed a share, with Harrison, of the prize of £25,000 offered by the Admiralty for the construction of a chronometer which would keep accurate time at sea. The Admiralty had acted very badly over the whole matter, and even Harrison had to fight hard for his proper reward; Earnshaw's claim was rejected out of hand, and this rebuff caused him great mental distress. He issued an Appeal to the Public for Justice, and later he did receive some compensation. In any case, there was certainly no doubt about his skill.

The Primate had also ordered a Ramsden transit instrument and a meridian circle, but these were blocked by his unhelpful heirs; the transit instrument ended up in Moscow, and the meridian circle in Palermo.. A transit instrument was later made for the Observatory by a local watchmaker, but, needless to say, it could not be compared with what Ramsden would have produced. Evidently the whole affair led to considerable bitterness. and it is worth noting a comment made much later, in December 1825, by the third Director of the Observatory, Romney Robinson. Writing of Ramsden's transit instrument, he says:5 "The princely-minded founder of the Observatory died before it was completed, and, from circumstances which need not be detailed, those which he had ordered were not obtained by the Observatory. It has at present a transit of 2 in. aperture. . . but no instrument for polar distances except Troughton's equatorial, which, though excellent, is by no means capable of entering into the field with large meridian circles."

Troughton Equatorial

The Troughton equatorial arrived in December 1795, and was mounted under the dome on two stone piers which rested on a massive pillar. The mounting was itself extremely massive, and of what is termed the English type; for its period it was extremely efficient - and yet the object-glass of the telescope had an aperture of only 2.5 inches and a focal length of three feet. By modern standards this is puny indeed, but for a long time it represented Armagh's main equipment. It was used for general observations, and with it Hamilton and his assistants determined the declinations of 37 standard stars; the results were published by Pond, afterwards Astronomer Royal, in 1806.6

So far as the watchmaker's transit instrument was concerned, Hamilton put it to what use he could, and observations of the Sun, Moon and standard stars were begun; they were in fact continued until the instrument was finally dismounted in 1827, but not many of them were ever published. A few came out in the Transactions of the Royal Irish Academy,7 and Hamilton also made a series of measurements of the Sun's apparent diameter between 1794 and 17958, in order to test the accuracy of some micrometers by Dollond. And that, so far as can be ascertained, was the sum total of the observational work done at Armagh under its first two Directors. No wonder that Romney Robinson commented much later that "under such circumstances, no work of any real value to Astronomy could be done"2.

The fact that there were no immediate financial troubles was due partly to the precautions taken by the Primate when he endowed the Observatory (and which his heirs had been unable to upset), and partly to Hamilton's own personal wealth. He even maintained an assistant; in succession, a Mr. Palmer (1793), Mr. Gimingham of Caius College, Cambridge (1793-6), Mr. Bradyn (1797-9) and then the Rev. Robert Hogg, a Presbyterian minister, who held office for more than thirty years. During the latter part of Hamilton's regime it seems that Hogg carried out most of the observations with the transit instrument. Hamilton published a few papers here and there; one in 1797, for instance, dealing with longitude determination9 and another describing uncertainties in the value of the solar parallax10. Yet all things considered, the achievements during the first few decades of the Observatory's existence fell far short of what its Founder must have hoped.

Robert Hogg

On 31 November 1815, Hamilton died at the Observatory, and was buried at Mullabrack. He was succeeded by the Rev. William Davenport, who held office for almost eight years.

Davenport's period of Directorship was remarkably barren, and it is difficult to avoid the conclusion that nothing astronomical was done apart from some desultory observations made by Hogg with the transit instrument. Nothing was published, and the general situation appears to have been one of total inertia. Yet Davenport himself was a highly competent scholar. He was privately educated by a Mr. Dwyer, about whom our ignorance is complete, after which he entered Trinity College (6 November 1787) and obtained a scholarship in 1791. He graduated as a B.A. in the following year, becoming a Fellow in 1795; his M.A. degree followed in 1796 and his D.D. in 1808, while in 1812 he became a Senior Fellow. He became Professor of Natural Philosophy at Trinity in 1807, and Archbishop King's Lecturer in 1815; from 1822 he was Rector of Clonfeacle in the diocese of Armagh.

This is all very well, but academic qualifications do not necessarily make a man into a successful administrator - which Davenport can hardly have been. Probably he had good excuse for his apparent laxity, since his marriage was not a happy one. There is a significant entry in the Observatory Minute-book, referring to "a visitation of the Governors held on 17 August 1820"; the agent was instructed to write to Mrs. Davenport, "informing her that the House and Offices were not found in sufficient repair, and that she is required to put the whole forthwith into a proper state, and to place them under the care of a person qualified to keep them in good order".

Perhaps fortunately, Mrs. Davenport's reactions to this directive are not recorded in the Minute-book or anywhere else. Finally, on 28 July 1823, the luckless Dr. Davenport committed suicide in the Director's study. A couple of pencilled notes written by Dr. Dreyer almost a century later state that Davenport "died by his own hand, according to Dr. Robinson because his wife was an absolute fiend. Dr. R. had great difficulty in getting her out of the Observatory". The only later entry in the original Minute-book is that Mrs. Davenport was paid the sum of £60 for her husband's astronomical instruments.

It is an unhappy story, and one's sympathies go out to Dr. Davenport. Certainly he left the Observatory in a bad state, but by good fortune he was succeeded by one of Armagh's greatest directors - the Rev. Thomas Romney Robinson, who was appointed a few weeks later by the new Primate, Lord John George Beresford.


* Part of the cost of the original Greenwich Observatory was defrayed by the sale of what was officially called "old and decayed gunpowder"- a manoeuvre somewhat typical of Charles II. Yet the "Merry Monarch" was a true scientific enthusiast. as Newton, among others, had reason to know.

  

Last Revised: 2013 July 18th