The largest telescope in the world for over 70 years, Leviathan’s reflecting lens measured 6 feet in diameter, 5 inches thick, and weighed in at 6 thousand pounds. When pieced together, the whole structure weighed more than 24 thousand pounds. Constructed in 1845, the 72 inch mirror wasn’t outdone until 1917, when the Hooker telescope had a mirror diameter of 100 inches. The purpose of the massive telescope was to further study nebulae and star clusters. The importance of this work became evident when the telescope revealed that many of the documented nebulae were actually galaxies. The larger mirror showed William Parsons, the telescope’s owner and operator, a spiral design in these nebulae, allowing him to more accurately catalogue celestial objects with drawings based on what he saw.
The telescope was no longer used by 1908, and was partially deconstructed. One of the 6 foot mirrors made for the telescope is now on display at the Science Museum in London. It wasn’t until the 1990’s that restoration went under way, and a new mirror was made for the Leviathan.