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Marlborough College
Oxford Astrophysics
Green Templeton College

Joseph Gurney Barclay FRAS (1816-1898), a Victorian astronomer and the restoration of his 1860 10" Cooke refractor

(article for Astronomy and Geophysics by Charles Barclay FRAS)

The mid 19th century saw a proliferation of interest in Astronomy and in the number of sizeable telescopes commissioned and observatories built. The ownership of a telescope became desirable for wealthy gentlemen and indeed there was a sense of one-upmanship when it came to size (aperture). The superb engineering in brass and bronze and the optical quality, due to excellence in lens making, made them not only important research tools but also objects of great beauty that they remain today.

In 1816 Joseph Barclay [picture courtesy of Joseph Gurney Barclay, Latimer, Bucks] was born into the banking family, gt-gt-grandson of David Barclay of Cheapside, the first of the Scottish Barclays to move south and who set up lodgings in the City of London near St Pauls'. Joseph was born in Norwich but shortly moved to Clapham, where his grandfather Robert Barclay had been a keen astronomer and had constructed an observatory in the grounds of his house, where with a friend Thomas Collington regular observations were made. Collington and Barclay were friends with William Hershel and visited and observed with him in Bath. Robert died in 1816, but it may be supposed that Joseph had access to the telescope there or at least books on Astronomy. From Clapham, Joseph's father moved with his young son to Knotts Green House in Leyton, Essex, within easy reach of the City. Joseph grew up there and became first a Partner and then Head of the banking firm of Barclay, Bevan & co. In the sizeable 'pleasure gardens' of the house Joseph built an observatory (though as yet no plans or pictures have been discovered). A description of the observatory and its collection of instruments is given in the Leyton Observations vol. II (held in the RAS library). The observatory housed a 7.5 "refractor and a Meridian Circle by Troughton and Sims. Joseph was a 'kind and gentlemanly' [1], being involved in many charitable organisations. Like his family before him he held strong Quaker beliefs and these encouraged the desire for increase in knowledge. In 1856 Barclay announced the discovery of a companion star to Procyon (°°Canis Minor ) [2].To enhance his observational capabilities he ordered a 10" refractor from Thomas Cooke and Sons in York. In order to maximise its usage he employed professional astronomers from Europe. First Hermann Romberg (a pupil of Encke) from 1862 till 1864 (when Romberg returned to Berlin to fill Encke's post) and then Charles George Talmage (originally RGO) from 1865 till 1886. Between the three of them they published papers in the RAS Monthly Notices from 1862 till 1884 [3]. Their observations are also published in the 4 Volumes of the Leyton Observations 1870, on comets, planets (especially Jupiter and its moons) [drawing by JGB courtesy RAS Library] but particularly Double Star measurements [4 for which the telescope was ideally suited. They added to and provided confirmation of many of the measurements made at larger observatories, which eventually lead to the completion of Struve's catalogue of Double Stars. When age and ill health affected Talmage, Barclay's use of the telescope dwindled. When approached by the Radcliffe Observer Edward Stone FRS in 1885 who was seeking a decent non-transit instrument for the Radcliffe Observatory in Oxford (now housing Green College) since they were lagging behind Cambridge with their facilities, JGB agreed to give his instrument to the observatory where it was named the Barclay equatorial (given its German Equatorial mount). From 1887 till 1934 the Barclay telescope was extensively used, first in a temporary wooden 'shed' [5] [picture Radcliffe papers] and then in the Heliometer Dome (from 1907). Its work again focussed on Double Stars, though it also recorded arguably the first fading light curve of the 1892 nova explosion in Auriga [6]. By the 1930s the light pollution on Oxford had become such that a move for the Radcliffe Observatory was inevitable and following a decision to relocate to South Africa (its present location) the fate of the Victorian instruments had to be decided. It appears that they were offered to a number of educational institutions. The large double refractor went to London University and is sited at Mill Hill. Marlborough College in Wiltshire raised 800 guineas (under the auspices of Sir Basil Blackett KCB, KCSI 1882-1935) to move and house the 10" on the fields above the town on the southern slopes of the Downs out of the glare of Swindon's increasing light pollution. The site was chosen by Dr FJM Stratton, Professor of Astrophysics at Cambridge. The Observatory building was constructed by local builders and a Dome purchased from an individual in Torquay. The Observatory was opened in 1935 by Dr Harold Knox-Shaw (1885-1970) the last UK based Radcliffe Observer. Over the ensuing decades the telescope saw use on and off by enthusiastic staff and pupils within the College. By 1997 however it was in a poor state of repair. Without a knowledge of the telescope provenance, a decision was made to restore it and to attempt to computerise a novel drive mechanism for both RA and Dec. axes. After 5 years work by E. Norman Walker (ex RGO) and following considerable support from the College, the telescope and observatory were reopened by Savilian Professor Joe Silk FRS in October 2002. Since then with refinements for the drives and the addition of solar filters, the telescope now operates on a full schedule for the College pupils (15 or so of whom take Astronomy GCSE each year) and for visiting groups of local people and local Primary Schools. Keeping the original Oxford connection, the Oxford Astrophysics Department is now involved and Graduates are helping out with the Public programme, thanks to a P.U.S. Small Awards grant from PPARC. School evenings and public lectures and events are scheduled throughout the year and two Summer School courses use the telescope each August.


  1. Dictionary of Quaker Biographies (unpub.) Library Friends House, London
  2. MN RAS 1863 p.196
  3. MN RAS vols: 23, 26, 34, 41, 44, 45, 59
  4. A Handbook of Double Stars. Crossley, Gledhill and Wilson, pub. MacMillan 1879
  5. Radcliffe Trust papers (Bodleian) DD Radcl d43
  6. MN RAS vol. 53 1892 p.35

I would like to acknowledge the help and assistance given by Peter Hingley, RAS Librarian, Professor Roger Davies, Department of Astrophysics Oxford University, Dr Roger Hutchins, Magdalen College Oxford and Anne Charles (ex Radcliffe Infirmary)

C.E. Barclay is currently Director of the Marlborough College Blackett Observatory and teaches Physics and Astronomy GCSE at Marlborough College.