Offaly's Scientific Tradition:The 3rd and 4th Earls of Rosse

By Declan McSweeney
In Ireland's Own Summer Annual 1988

Offaly has produced a number of scientists, the best-known being the third and fourth Earls of Rosse.

William Parsons, Third Earl, began his experiments on the improvement of reflecting telescopes in 1827. In 1839, his first 36-inch 3ft. reflector was completed and in 1845 his sensational 72 inch telescope was assembled. This leviathan remained the world's largest telescope until 1917. It witnessed the discovery that nebulae could be resolved into separate star systems beyond the Milky Way.

In 1914 the lens was removed and taken to the Science Museum in London. One of the reasons given for its removal was the fear that it might be lost to Germany as the first World War got under way.

Whatever the real reason was for its removal, it is now irrelevant and many people in Birr - and elsewhere - feel that the time for its return home is long overdue. Much of the original structure is still intact and as a tourist attraction a restored Rosse Telescope could cause as much excitement today, as it originally did almost 150 years ago.

Sir 'William's eldest son, Laurence, who eventually became the fourth earl, began research into the heat of the moon in 1868, and confirmed the discovery of the satellites of Mars in 1877, while another younger son, Charles, became an outstanding scientist, but instead of studying the stars Charles was fascinated by steam power.

He invented a revolutionary process for more efficient generation of electricity. It proved successful, but its uses were far reaching and the Parsons Steam Turbine was a milestone in maritime history.

The old piston-and-cylinder steam engine had developed as far as it could with triple, and even quadruple, expansion capabilities. Charles's approach to harnessing steam power was totally different. In his engine a jet of steam turned a multi-bladed shaft which was directly connected to the propeller. This system made pistons redundant, and he proved its efficiency in a most dramatic way.

At the Spithead Naval Review in 1897 Britain's warships paraded in celebration of Victoria's Diamond Jubilee on the throne. Among them was a small steam launch which Parsons had designed and fitted with his steam turbine engine. It was appropriately called Turbinia.

Accounts vary as to whether the Turbinia was officially present or whether she had gate-crashed. Even if Parsons had been invited to exhibit the launch the manner in which he exhibited it was certainly unexpected.

The turbine engine was given full power and the Turbinia streaked through the fleet at an astonishing 34.5 knots. Torpedo boats were sent to intercept her but the Turbinia simply could not be caught.

Charles Parsons had proven the sceptics wrong - as his father had done in a different scientific field a generation earlier. Within decades Parsons steam turbine had made the reciprocating steam engine as obsolete as the age of sail.

Incredibly, while all this was going on, yet another brother Clere Parsons was making a famous name for himself as a railway builder in South America.

Notwithstanding, the Parsons family were not the only people in Offaly to take an interest in astronomy. Charles Jasper Joly, born in St. Catherine's Rectory, Tullamore in 1864, became Astronomer Royal for Ireland in Dunsink in 1897. His was another very brilliant family, as his cousin Jasper Robert Joly, born in Clonsast in 1819, qualified to enter T.C.D. when only 13.

And finally, John Joly (1857-1933) brother of Charles Jasper became Professor of Geology at Trinity College Dublin and won international fame by measuring the age of the oceans through studying the rate of deposit of sodium, later he devised a method of postulating the age of rocks. He also did research on the cooling of the earth, on radium extraction and on the radium treatment for cancer. As well as being a geologist, John Joly was equally at home as a physicist and engineer.

Birr - The World's Largest Telescope

Back to List

Site Hosted by Dotser

A-Z of Offaly - About Offaly - Community History - Famous People - Photographs - Maps - Town Crests - 19th Century Offaly