Astronomical Labourers: Maskelyne's Assistants at the Royal Observatory, Greenwich, 1765-1811

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<ul><li><p>Astronomical Labourers: Maskelyne's Assistants at the Royal Observatory, Greenwich, 1765-1811Author(s): Mary CroarkenSource: Notes and Records of the Royal Society of London, Vol. 57, No. 3 (Sep., 2003), pp. 285-298Published by: The Royal SocietyStable URL: .Accessed: 16/06/2014 03:50</p><p>Your use of the JSTOR archive indicates your acceptance of the Terms &amp; Conditions of Use, available at .</p><p> .JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact</p><p> .</p><p>The Royal Society is collaborating with JSTOR to digitize, preserve and extend access to Notes and Records ofthe Royal Society of London.</p><p> </p><p>This content downloaded from on Mon, 16 Jun 2014 03:50:50 AMAll use subject to JSTOR Terms and Conditions</p><p></p></li><li><p>Notes Rec. R. Soc. Lond. 57 (3), 285-298 (2003) doi 10.1098/rsnr.2003.0215 </p><p>ASTRONOMICAL LABOURERS: MASKELYNE'S ASSISTANTS AT THE ROYAL OBSERVATORY, GREENWICH, 1765-1811 </p><p>by </p><p>MARY CROARKEN </p><p>Visiting Research Fellow, Department of Computer Science, University of Warwick, Coventry CV4 7AL, UK </p><p>SUMMARY </p><p>Nevil Maskelyne FRS held the post of British Astronomer Royal from 1765 to 1811. As Astronomer Royal, Maskelyne's main task was to ensure that the positions of the Sun, Moon, planets and stars were regularly observed and that those observations were pub- lished in an accessible form. To do this, and simultaneously to maintain his role within London's scientific society, Maskelyne hired an assistant to undertake the routine work of the Observatory. This paper considers Maskelyne's assistants at the Royal Observatory, Greenwich, identifies who the assistants were, and describes their working conditions. </p><p>INTRODUCTION </p><p>Nothing can exceed the tediousness and ennui of the life the assistant leads in this place, excluded from all society, except, perhaps, that of a poor mouse which may occasionally sally forth from a hole in the wall, to seek after crumbs of bread dropt by his lonely companion at his last meal. This, of course, must tend very much to impede his acquiring astronomical information, and damp his ardour for those researches which conversation with scientific men never fails to inspire. Here forlorn, he spends days, weeks, and months, in the same long wearisome computa- tions, without a friend to shorten the tedious hours, or a soul with whom he can converse. He is also frequently up three or four times in the night (an hour or two each time), and always one week in the month when the moon souths in the night time, with the owls perched on the fir-trees in the park below, screaming by way of answer to him when he opens the sliding shutters, in the roof of the building, to make his observations. </p><p>Thomas Evans, assistant at Royal Greenwich Observatory 1796-981 </p><p>The description above paints a very gloomy picture of life as an assistant at the Royal Observatory, Greenwich (figure 1), at the end of the eighteenth century. The assistant's job was to make astronomical observations, reduce the collected data and perform astro- nomical computations under the supervision of Nevil Maskelyne, Astronomer Royal 1765-1811 (figure 2). Employing an assistant gave Maskelyne time away from the rou- tine work of the Observatory to be an active member of The Royal Society and the sci- entific establishment of the day. </p><p>Maskelyne's assistant lived and worked at the Royal Observatory, situated on a hill in Greenwich Royal Park overlooking the Thames. London was more than 4 miles away. </p><p>285 ? 2003 The Royal Society </p><p>This content downloaded from on Mon, 16 Jun 2014 03:50:50 AMAll use subject to JSTOR Terms and Conditions</p><p></p></li><li><p>286 Mary Croarken </p><p>Figure 1. The Royal Greenwich Observatory. Photograph copyright C National Maritime Museum, negative number D5611. </p><p>From comments such as those above we are left in no doubt that the life of an assistant at the Royal Observatory was lonely and tedious. John Pond, Maskelyne's successor as Astronomer Royal from 1811 to 1835, confirmed the view that the assistant's role was that of an astronomical labourer. Speaking about the type of person he wanted to employ as an assistant, Pond wrote: </p><p>I want indefatigable hard working &amp; above all obedient drudges ... men who will be contented to pass their day in using their hands &amp; eye in the mechanical act of observing &amp; the remainder of it in the dull process of calculation.2 </p><p>During the regime of George Biddell Airy, Astronomer Royal 1835-81, computing assis- tants were typically young men taken on as teenagers. Although the best and brightest were kept on and given permanent positions, most were dismissed and replaced by the age of 23, before they had to be paid higher wages. </p><p>The notion that the Greenwich assistants were drudges is one that is firmly established by commentators,3 but who were these people? This paper examines the Royal Observatory assistants during the period 1765-1811 while Nevil Maskelyne was Astronomer Royal. Did they all feel as depressed by their situation as Evans obviously did, or were some happy with their lot? Did they use working at the Observatory as a </p><p>This content downloaded from on Mon, 16 Jun 2014 03:50:50 AMAll use subject to JSTOR Terms and Conditions</p><p></p></li><li><p>Maskelyne ' assistants at the Royal Observatory, Greenwich, 1765-1811 287 </p><p>Figure 2. Nevil Maskelyne, from an engraving by E. Scriven from a painting by Vanderburgh. Photograph copyright C National Maritime Museum, negative number ROG 11498. </p><p>chance to gain experience before moving on to better things, or were some of them con- tent to stay for many years? </p><p>LIFE AS AN ASSISTANT AT THE ROYAL OBSERVATORY, GREENWICH </p><p>Nevil Maskelyne (1732-1811), elected FRS in 1758, was appointed fifth Astronomer Royal in 1765 and held the post until his death in 1811. Maskelyne achieved a great deal while Astronomer Royal, including regular publication of the Greenwich observations, the creation of the annually published Nautical almanac for navigation at sea, and exper- imentation on the gravitational pull of mountains. He is remembered as an honest and popular member of the scientific community of eighteenth-century London.4 The princi- pal work at Greenwich was to observe the positions of the Sun, Moon, planets and stars and to publish these data. This was a considerable undertaking because not only did the observations need to made, frequently at night, but they also needed to be reduced, i.e. corrected for refraction, parallax, instrument error, and so on, and a fair copy had to be made. To perform most of these duties Maskelyne hired an assistant. </p><p>This content downloaded from on Mon, 16 Jun 2014 03:50:50 AMAll use subject to JSTOR Terms and Conditions</p><p></p></li><li><p>288 Mary Croarken </p><p>Figure 3. The Observatory building (now known as the meridian building), where the Greenwich assistants lived and worked. The assistant's computing and sitting room was on the ground floor and his bedroom was above. On each side were telescopes, for which the roof doors can be clearly seen. Photograph copyright ? National Maritime Museum, negative number D5599 (cropped). </p><p>Maskelyne expected his assistant to be available for regular observing duty between 7 o'clock in the morning and 10 o'clock in the evening every day of the week.5 The assis- tant was not required to work for 15 hours a day but to be available on stand-by for observing duties. In addition the assistant was expected to get up in the night to observe specific phenomena, but Maskelyne did try to organize the observing schedule so that night observation was kept to a minimum. The stars he chose for regular observations were bright and could often be seen during the day, at dawn or dusk. Sometimes night observing was unavoidable and the schedule at these times was undeniably arduous. For example, for a two-week period in November 1794, Maskelyne's assistant was averag- ing only two hours sleep a night, but this was exceptional. When not observing, the assis- tant performed computing work to 7 or 8 o'clock in the evening. Maskelyne did not expect his assistant to compute on a Sunday but he did expect him to observe. The assis- tant lived at the Observatory as part of the Astronomer Royal's household but his rooms were in the Observatory building (figure 3) and not in the Astronomer Royal's residence. He (for they were all male) had a sitting and computing room on the ground floor and above that a bedroom accessed by a spiral staircase. The bedroom was fitted with an alarm mechanism that woke the assistant during the night if necessary. The room to the east of the assistant's quarters held the transit telescope and the room to the west the </p><p>This content downloaded from on Mon, 16 Jun 2014 03:50:50 AMAll use subject to JSTOR Terms and Conditions</p><p></p></li><li><p>Maskelyne ' assistants at the Royal Observatory, Greenwich, 1765-1811 289 </p><p>zenith quadrant. The assistant's meals were often taken alone; the footman had instruc- tions to clean his shoes and the assistant had access to Maskelyne's scientific library.6 </p><p>The observing schedule for the Observatory was heavy and the regulations under which the Observatory operated prevented both the Astronomer Royal and his assistant from being absent at the same time. Maskelyne, like many of his scientific contempo- raries an ordained minister of the Church of England, annually visited his parish living in Wiltshire and regularly attended Royal Society and other meetings in London, where he was very much part of the scientific establishment. In practice this meant that his assistant was expected to carry most of the observing load, although in fairness the observing books show that Maskelyne also regularly observed when in residence. During any day on which the weather was favourable, the Sun, the Moon, the principal fixed stars and the planets were to be observed provided they were in suitable celestial posi- tions. In addition, occultations of fixed stars by the Moon and eclipses of Jupiter's satel- lites were also to be observed. </p><p>Because of the intensity of the observing schedule it was very difficult for assistants to leave Greenwich for any length of time. One assistant, David Kinnebrook (assistant 1794-96), occasionally spent a day in London, often for the purpose of collecting his wages from the Tower of London, but other requests to make visits further a field were turned down by Maskelyne.7 Sundays were often his only opportunity to visit friends or to dine away from the Observatory. Other assistants also found that their ability to main- tain a social life was hampered by their observing schedule. Thomas Firminger, assistant 1799-1807, made arrangements to visit his friends only on the proviso that the weather was poor and unsuitable for observing.8 It is also clear that both Kinnebrook and Firminger tried to arrange for their friends to visit the Observatory at times when they knew Maskelyne and his family would be away-a sign that Maskelyne did not encour- age his assistants to waste time socializing.9 </p><p>Maskelyne also discouraged his assistant from taking an active part in the wider math- ematical community. For example, Maskelyne explicitly disapproved of his assistant's publishing answers to the questions set in the Ladies Diary, an annual almanac that included mathematical problems to which readers sent in answers for publication in the following edition.'0 None of Maskelyne's assistants are recorded as having contributed to Ladies Diary while employed at Greenwich, although at least eight of them did so at other times." No doubt the reason behind this restriction was to concentrate his assis- tant's mind on his work rather than on more varied, and more interesting, mathematical puzzles, but it must also have added to the feeling of isolation that many of his assistants felt. David Kinnebrook's father was concerned that this isolation was contributing, along with night-time observations, to the decline of his son's health. Although Kinnebrook senior had been keen for Kinnebrook junior to better himself using the resources of Maskelyne's considerable library when he had first taken up residence at Greenwich, 18 months later he was advising his son to go to a public house, specifically the Greyhound, 'as often as you can in a week without neglect of business' and to get hold of 'books of voyages, travels would divert and improve, and even good novels' from a library. His father also encouraged him to try and widen his social circle by getting to know some 'decent well behaved person'.12 </p><p>This content downloaded from on Mon, 16 Jun 2014 03:50:50 AMAll use subject to JSTOR Terms and Conditions</p><p></p></li><li><p>290 Mary Croarken </p><p>THE WORK OF AN ASSISTANT AT THE ROYAL GREENWICH OBSERVATORY </p><p>Lunar and stellar transit observations accounted for about 80% of the observations made at Greenwich during Maskelyne's time. The observations were taken by the ear and eye method of observing developed by James Bradley, the third Astronomer Royal. The eight-foot transit telescope used by Maskelyne was made by Bird and installed in 1750. Across the image plane of the telescope were five vertical wires. The observer had to watch while the celestial body approached each wire and at the same time note the time on the transit clock. While watching the transit, the observer had to listen for and count the one-second beats of the clock. As the celestial body passed the wire the observer had to judge the spatial distance of the star at the clock beat before the transit and the clock beat after the transit and then give an estimate of the time of the transit to the nearest one- tenth of a second. Each transit observation was taken as the mean of five separate obser- vations on average about 40 seconds apart.'3 A good deal of skill was needed to take consistently accurate observations, and not all assistants acquired it. Not only did the assistants have to deal with the pressure of taking accurate observations sometimes very close together, but they suffered from interrupted sleep patterns and were expected to observe in very cold weather in the middle of winter. This regime took its toll on the health of a least one assistant....</p></li></ul>