20-559: The Hamilton Walk from Dunsink Observatory to Broom Bridge on the Royal Canal in Dublin takes place on 16 October each year. This is the anniversary of the day in 1843 when William Rowan Hamilton discovered the non-commutative algebraic system known as quaternions , while walking with his wife along the banks of the Royal Canal . The walk was launched in 1990 by Prof Tony O'Farrell of
40-425: A Cauchoix of Paris lens) in the 1830s on a Thomas Grubb mount. The problem for James South's telescope was the equatorial mount. South was involved in a notorious lawsuit brought against him by the instrument maker Edward Troughton over this equatorial-mount telescope which the latter had constructed for him, and which South considered defective. Troughton sued him for payment and won. South promptly demolished
60-667: A Fellow of the Royal Society of London and in 1822 a Fellow of the Royal Society of Edinburgh his proposer being Edward Troughton . He won the Copley Medal in 1826 and the Gold Medal of the Royal Astronomical Society in that same year. He was knighted by King William IV in 1831. Starting around 1826, James South made plans for a new, larger telescope, an equatorially mounted achromatic refractor (a telescope with
80-527: A lens) in a new observatory. He bought a 12-inch (actually about 11.8) aperture lens from Robert-Aglaé Cauchoix in Paris for about 1000 pounds, large enough to be the biggest achromatic object lens in the world at the time. The telescope for the lens was completed, but dismantled around 1838. The next largest refractor, was at the Markree Observatory , which successfully completed a 13.3-inch refractor (also
100-626: A petition was successfully submitted to obtain a Royal Charter, whereupon it became the Royal Astronomical Society . He was born in Southwark in London in October 1785, the son of James South, a pharmaceutical chemist. John Flint South was his younger half-brother. He originally trained as a chemist, then as a surgeon, but his interests in astronomy overtook all things. In 1821 he was elected
120-499: Is now used mainly for public 'open nights'. The observatory is currently part of the DIAS. It provides accommodation for visiting scientists and is also used for conferences and public outreach events. Public talks on astronomy and astrophysics are given regularly at the observatory by professional and amateur astronomers. Stargazing events are also held using the Grubb telescope. The observatory
140-595: Is one of the locations featured in the book, The Coroner's Daughter by Andrew Hughes, which was selected as the Dublin UNESCO City of Literature One City One Book for 2023. James South Sir James South (October 1785 – 19 October 1867) was a British astronomer . He was a joint founder of the Astronomical Society of London, and it was under his name, as President of the Society in 1831, that
160-623: The Dublin Institute for Advanced Studies (DIAS) and unveiled by the Taoiseach Éamon de Valera in 1958 marks the spot where he recorded his discovery. Many prominent mathematicians have attended the event; they include Wolf Prize winner Roger Penrose (2013), Abel Prize and Copley Medal winner Andrew Wiles (2003), Fields Medallists Timothy Gowers (2004) and Efim Zelmanov (2009), and Nobel Prize winners Murray Gell-Mann (2002), Steven Weinberg (2005) and Frank Wilczek (2007). At
180-449: The townland of Dunsink , 84m above sea level. The South Telescope, a 12-inch Grubb instrument, is a refracting (i.e. it uses lens) telescope built by Thomas Grubb of Dublin and completed in 1868. The achromatic lens, with an aperture of 11.75 inches, was donated by Sir James South in 1862, who had purchased the lens from Cauchoix of Paris 30 years earlier. He had intended it for a large but troubled equatorial that came to fruition in
200-581: The "Royal Astronomer of Ireland," an appointment first filled by Dr. Henry Ussher, and subsequently by Dr. Brinkley, Bishop of Cloyne. The Institution is amply furnished with astronomical instruments, and is open to all persons interested in astronomical science, on introduction to the resident Assistant. It is situated in Lat. 53° 23' 13" N., Long. 6° 20' 15" W. Dublin Mean Time , the official time in Ireland from 1880,
220-462: The 1830s, but was dismantled around 1838. (See also Great refractors ) The entry for the observatory in Thom's Directory (1850) gives the following account of the observatory, ::ASTRONOMICAL OBSERVATORY OF THE UNIVERSITY OF DUBLIN, DUNSINK This Observatory, endowed by Francis Andrews, esq., LL.D., Provost of Trinity College, and erected in 1785, was placed, by statute, in 1791, under the management of
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#1732908777758240-522: The Department of Mathematics at St Patrick's College, Maynooth . It starts at DIAS Dunsink Observatory , where Hamilton lived and was the Director from 1827 to 1865, and ends at the spot where he recorded his discovery by carving the following equation on Broom Bridge : These are the basic relations which define the quaternions. The original inscription by Hamilton is no longer there, but a plaque erected by
260-414: The Royal Canal. Dunsink Observatory The Dunsink Observatory is an astronomical observatory established in 1785 in the townland of Dunsink in the outskirts of the city of Dublin , Ireland . Dunsink's most famous director was William Rowan Hamilton , who, amongst other things, discovered quaternions , the first non-commutative algebra form, while walking from the observatory to
280-409: The city with his wife. The annual Hamilton Walk that commemorates this discovery begins at the observatory. He is also renowned for his Hamiltonian formulation of dynamics . The observatory was established by an endowment of £3,000 in the will of Francis Andrews , who was Provost of Trinity College Dublin at his death on 18 June 1774. The site was established on the south slope of a low hill in
300-455: The end of the 1990s, O'Farrell's younger colleague Fiacre Ó Cairbre took over the organisation of the walk, but O'Farrell always gives a speech at Broome Bridge. O’Farrell and Ó Cairbre received the 2018 Maths Week Ireland Award for "outstanding work in raising public awareness of mathematics" resulting from the founding and nurturing of the Hamilton walk. It has been argued that the discovery of
320-406: The observatory, for which it was given responsibility. The named chair Andrews Professorship of Astronomy was associated with the directorship of Dunsink Observatory during the time that the observatory was part of Trinity College Dublin (TCD). By the late 20th century, the city encroached ever more on the observatory, which compromised the seeing . The telescope , no longer "state of the art",
340-496: The quaternions, by revealing deep mathematical structures that did not obey the commutative law, allowed mathematicians to create new systems unbound by the rules of ordinary arithmetic. It follows that the climax of the Hamilton walk at Broom Bridge marks the exact spot where modern algebra was born. The Hamilton Way is a proposed foot and cycle path that follows the route of the Hamilton Walk, linking DIAS Dunsink Observatory to
360-581: The telescope mount; the 12-inch lens, which had been purchased separately, was preserved and presented to the (Dublin) Dunsink Observatory in 1862. The Observatory mounted it on a Grubb equatorial, where it survives to the present day. (See also Great refractors ) James was the second owner of the Groombridge Transit Circle of 1806 (after Stephen Groombridge ). He died at the observatory on Campden Hill in Kensington on 19 October 1867, and
380-442: Was buried on the west side of Highgate Cemetery . In 1816 he married Charlotte Ellis (d.1851). She was an heiress and his new-found wealth enabled him to give up surgery and concentrate on astronomy. South and John Herschel jointly produced a catalogue of 380 double stars in 1824, reobserving many of the double stars that had been discovered by William Herschel . South then continued and observed another 458 double stars over
400-452: Was the local mean time at Dunsink, just as Greenwich Mean Time (GMT) is the local mean time at Greenwich Royal Observatory near London. In 1916, Ireland moved to GMT. In 1936, Trinity College stopped maintaining the observatory and rented out the land. Éamon de Valera , who had driven the establishment of the Dublin Institute for Advanced Studies (DIAS) in 1940, added a School of Cosmic Physics to it in 1947, partly in order to revive
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