Restoration of the Great Telescope (Page 2)

Page 3 | Page 1

The universal joint and restored windlass
© Birr Castle Archives

The old telescope tube and mirror housing was removed in March 1996 and a new tube was installed within the retaining walls in September 1996. The two windlasses required to lift the telescope and the lower platform were missing from the site, but a similar windlass was donated and, after complete restoration and the fitting of a new drum, it was installed at the north end of the observatory. The Third Earl had two Meridian Stones buried in the grounds to properly align the North South axis of the telescope. By the time of the restoration, however, the north stone had been lost and a new stone was laid to replace it.

A computerised, motorised system of operation was installed with the option of manual control. and a computer program also allows for daily demonstrations of the operation and range of movements of the telescope components.

Equally important tasks completed by February 1997 included the correct fabrication and installation of the circular meridian arc, which guides the vertical tracking of the telescope tube and the correct selection of mechanical gearing for the windlass which drove the lifting chain. Major efforts were taken to hide any modern features of construction so as to achieve the goal of reconstructing the "Leviathan of Parsonstown" to its original 1845 appearance.

Top | Page 3 | Page 1