The Royal Canal

The Royal Canal is the second of the canals that reach the Shannon River from Dublin, and was opened in 1817 some thirteen years after the Grand Canal. Work began in 1790 and the total cost of construction was £1,421,954.

It is 90 miles long and there are 46 locks to navigate. On its way from Dublin it passes through Maynooth, Enfield, Mullingar and Ballymahon. At the Dublin end it passes by Croke Park, where the terrace close to it is called the ‘Canal End’ before it reaches Spencer Dock then the Liffey, and the Dublin Bay beyond.

Brendan Behan memorial at Whitworth Road

The canal was constructed for the dual purpose of freight movement and passenger transport to-and-from the centre of the country. It was very popular and profitable for many years before being slowly undermined by the introduction of the railway, and later by road haulage. And by the 1970s it had fallen into disuse and plans were considered to fill in sections of it and construct a road. These, thankfully, were challenged, and work by the Royal Canal Amenity Group and Waterways Ireland saw the canal fully reopened in 2010.

Broome Bridge, near Castleknock, has a special place in Irish and scientific history. For it was here, on the 16^th October 1843, that mathematician William Rowan Hamilton, who lived in Dunsink Observatory, in a moment of inspiration, realised the solution for quaternions, a problem he had been working on for some time. Excited by what he had discovered, he scratched the solution on the bridge with his penknife. This moment is celebrated annually at the bridge on the 16^th October, now known as Broome’s Day.

The canal has featured in a famous song from the play The Quare Fellow by Brendan Behan. It is set in Mountjoy Gaol where Behan had spent some time, and refers to the metal triangle that was beaten to waken inmates.

And the auld triangle went jingle-jangle

All along the banks of the Royal Canal

(Photo: Dennis Fisk)

William Rowan Hamilton – Genius

WRH in the Royal Irish Academy

The word genius is defined as ‘a person who displays exceptional intellectual ability, creativity or originality associated with the achievement of new advances in a domain of knowledge’ and it most definitely applies to William Rowan Hamilton.

Hamilton was born on the 4^th August 1805, the fourth of nine children, to Archibald Hamilton, a solicitor, and his wife Sarah and lived at 38 Dominick Street, Dublin. When he was three years old he was sent to live with his uncle James Hamilton, a teacher and linguist, who ran a school in Trim, County Meath, and showed an exceptional talent for languages from an early age. By the age of thirteen he had acquired the same number of languages, including ancient Latin and Greek, most modern European languages and Persian, Arabic and Sanskrit. Late in life he often relaxed by reading books in Persian or Arabic!

South Telescope

When he was eight he lost a mental arithmetic contest against the American prodigy Zerah Colburn who was touring Europe and astounding audiences with his ability. After his loss Hamilton devoted his time to mathematics and less to the study of languages. The year before he entered university he spotted an error in Laplace’s Mechanique Celeste, and this brought him to the attention of John Brinkley, the Royal Astronomer of Ireland. He said of Hamilton: ‘This young man, I do not say will be, but is, the first mathematician of his age.’  

He entered Trinity College when he was eighteen and studied mathematics and Classics gaining an unprecedented ‘optime’ in both. Soon afterwards, in 1827, he was appointed, while still an undergraduate, Professor of Astronomy at Trinity College. Although this was a great opportunity for Hamilton, which included a decent salary and the title of Royal Astronomer of Ireland, it was also a place for his sisters to live. However, he spent most of his time studying mathematics and very little effort was devoted to astronomy. He was, however, twice awarded the Cunningham Medal, the highest honour bestowed by the Royal Irish Academy. And in 1835 he was knighted for his services to science; and both he and Michael Faraday were awarded the Queen’s Medal by the Royal Society that same year.

Plaque on Broom Bridge

While on his way along the Royal Canal to a meeting in the Royal Irish Academy on 16^th October 1843 the discovery of quaternions took shape in his mind. He etched the equation on Broome Bridge and the famous event is celebrated each year with a walk from the observatory to the site. Today quaternions are used in computer graphics, signal processing and orbital mechanics. As such, their use can be found in todays’ spacecraft attitude-control systems, and their discovery played a significant role in putting Man on the Moon. That’s out of this world, and something the Dunsink Astronomer would have loved.

Dunsink Observatory

 

Dunsink Observatory – Eye on the Sky

Dunsink Observatory was one of those places in Dublin that I knew about, but had never visited. So it was a real treat to be shown around the historic building by Prof. Luke Drury (Dublin Institute for Advanced Studies) whose wealth of knowledge and anecdotes made for a most enjoyable and informative experience.

Dunsink Observatory – 1785

Clocks that kept ‘Dunsink’ time

The Observatory was built in 1785, and it was financed by funds from the will of Provost Francis Andrews of Trinity College, who wanted the college to have, for the first time, the facility to study astronomical science. Richard Myers designed it, and the original plans that called for two Palladian-style wings, were never completed due to financial restraints. As such, the building you see today is notable for its lack of ornamentation and is appealing, nevertheless, to a modern architectural aesthetic.
Although no major discoveries were made at the Observatory, it was made famous by Sir William Rowan Hamilton (1805-1865) who was appointed Professor of Astronomy and Director of Dunsink in 1827, while he still an undergraduate. He was Ireland’s greatest mathematician and his work on the foundations of mechanics underpins large areas of modern physics. His most famous discovery happened on 16th October 1843 at Broom Bridge, when he suddenly realised the solution to a problem that he had been working on, and scratched it into the stone on the bridge with his pocketknife. His discovery of quaternions, is a classic moment of revelation, and one of its main applications is in spacecraft attitude control systems.
The South Dome was erected in 1865 and the Grubb telescope is impressive, even after 150 years. Grubb was a firm based in Rathmines and it exported telescopes all over the world until the early 20th century.
Dunsink provided the correct time for Dublin and you can see the original clocks and other equipment inside the main building. And, not surprisingly, ‘Dunsink time’ is mentioned in James Joyce’s Ulysses.
The State bought the Observatory in 1947 and it is now part of the School of Cosmic Physics in DIAS. Today the Observatory is used for conferences, meetings and during the winter (Oct-Mar) for Open Nights when visitors can view celestial bodies (weather permitting!) though the Grubb telescope. Special family events are often held where parents and children can meet an astronomer and explore the night sky.  Carl  Sagan, the renowned cosmologist, was famous for his quotes and the following should be borne in mind, especially if you get to look through the Grubb telescope sometime:  ‘The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.’ I think that says it all!

South Dome

Grubb Telescope in South Dome