Survey Data
Reg No
14819269
Rating
National
Categories of Special Interest
Architectural, Historical, Scientific, Social, Technical
Original Use
Building misc
In Use As
Building misc
Date
1840 - 1850
Coordinates
205584, 205103
Date Recorded
31/08/2004
Date Updated
--/--/--
Description
Seventy-two inch reflecting telescope, built between 1841 and 1845, by William Parsons, the Third Earl of Rosse. Located within Birr Castle demesne. Timber telescope set within man-made hollow flanked by Gothic style ashlar limestone walls to east and west with pointed-arched recessed blind openings. Crenellated parapet to eastern wall. Crane mechanism on flanking walls and to the north of the telescope. Timber steps to southern terminus of flanking walls. Telescope site bounded by modern railings. Restored in 1995.
Appraisal
The world renowned astronomer, Patrick Moore, stated that 'the story of Birr astronomy is unique. Alone and unaided the Third Earl made what is by far the most powerful telescope ever constructed, and used it to such good effect that he was able to see further and more clearly than anyone before him. Nothing of the sort had ever happened before, nothing of the sort can ever happen again.' Its importance is underlined by the fact that it aided in the discovery of the Whirlpool Nebula in the 1840s. Indeed Birr telescope remained the most powerful telescope and the largest scientific instrument in the world until 1917. To add to its architectural appeal, it was embellished with Gothic arches and battlements so it could be seen as an ornamental as well as functional structure within the demesne setting.