Bob Strunz, University of Limerick, Ireland. strunzb@ul.ie +353-61-333644
What have Astronomy, Photography, Engineering and Horticulture got in common ? Obviously they are branches of the sciences, but there is a less obvious link, a family and their home in almost the exact centre of Ireland.
A few clues, between 1845 and 1915, the world's largest telescope, the invention of the steam turbine in 1884 and the world's first steam turbine powered ship in 1897.
The castle and estate at Birr, Co. Offaly in Ireland, has been owned by the Parsons family for over 300 years. In this time, Birr castle demense has seen a host of scientific and technological achievement, much of which has changed the world. To help preserve this heritage for future generations, the ``Birr Scientific and Heritage Foundation'' was formed.
The foundation has been charged with the task of developing an Historic Science Centre at Birr. The idea is to develop a centre which will act as a focus for the historical aspects of Irish science and technology. The University of Limerick has been involved with this project since its beginning and has been active in promoting the project both in Ireland and abroad. We think that it is extremly important that Irish people should have an awareness of the richness of our scientific heritage. We have traditionally been seen as a ``land of saints and scholars'' more involved with literary and artistic pursuits than the scientific, the Historic Science Centre at Birr will illustrate the scientific aspect of Irish creativity.
During the 19th century, the Parsons family made important contributions in the field of astronomy. From 1845 until 1918 the largest telescope in the world was located at Birr Castle. This instrument, known as the ``Leviathan of Parsonstown'' was a Newtonian reflector type telescope with a primary mirror diameter of 72 inches and weighing four tonnes. The primary mirror was cast from Speculum metal, ground and figured on the estate using local labour and machines which were designed by the third Earl of Rosse.
This enormous telescope, shown here in an early (circa 1850) photograph by Mary Rosse, was used to examine deep-space objects, and made many, previously unknown observations. In particular, the huge light-gathering power of the instrument allowed it to view faint objects, never before seen by the human eye. In 1845, the third Earl of Rosse found that some nebulae are spiral in shape. The first of these being Messier 51, the ``Whirlpool''. At the time, there was no celestial photography, therefore all of the observations were made with a sketchpad. The skill with which this was done is all the more remarkable when one realises that they were sketched in the dark, up to seventy feet above the ground. Indeed, comparisons between these early sketches and modern photographs reveal the remarkable visual acuity with which they were made. We see here on the right, a hand drawn picture of the whirlpool, juxtaposed with a modern image.
A further important contribution to the field of astronomy came from the fourth Earl of Rosse, who, using an apparatus designed and constructed at Birr made the first accurate estimate of the temperature of our closest neighbour in space, the moon.
Lady Mary Rosse, wife of the third earl, was an unusual woman for her time. Ironically, her most significant contributions, in the area of photography, actually spelled the death knell for the great telescope, which, due to the nature of its mounting, was not suitable for celestial photography.
The science of photography was in its infancy in the mid 19th century, the highly stable emulsions which are commonplace today, had not been invented. This meant that photography was more akin to chemistry than art. Photographers were forced to prepare their own sensitised plates from glass slides with a preparation of Silver Nitrate. The laboratory where she worked is shown above, as far as we know, this is the only mid 19th century darkroom still extant anywhere in the world. It will be preserved and displayed as part of the project.
Not only was Lady Rosse a photographer of note, she was also a skilled blacksmith and was responsible for the wrought iron work on the great telescope tube, and also for the magnificent gates to the estate, which are still in use today.
The Parsons name is synonymous with the invention of the steam turbine (Charles Parsons). While it is now taken for granted as a means of providing motive power for ships, it was not so easily accepted by a skeptical admiralty in the 1890's. Charles Parsons knew that the future for shipping lay, not with paddle wheels and piston engines, but with screw propulsion and steam turbines. Having received a less than enthusiastic response from the admiralty with regard to his invention, he set about proving his point in a characteristically unconventional manner.
The ``Turbinia'', a vessel of 110 feet in length, powered by steam turbine and twin screw propellers was built to his design. Her majesty queen Victoria was reviewing the fleet off Spithead on the occasion of her Diamond Jubilee in 1897 when the ``Turbinia'' hove in sight. She wove through the fleet at a speed of 34.5 knots, much faster than any of the fleet ships, the two fastest destroyers were sent after her, but she performed figures of eights around them. The point had been made, the admiralty set about employing the technology which is now a worldwide standard. The ``Turbinia'' is lying in England at present, and it is our hope that she will be brought back to Birr for preservation and display.
The project has been endorsed by the Irish government, and we are currently in the process of raising the private sector matching funds which are required to obtain government grant aid. The telescope restoration has been commenced and the initial outline designs for the centre are completed.
If you would like more information or have any queries about this project please email to Bob Strunz at the University of Limerick strunzb@ul.ie