Yesterday I was reading a wonderful article about early astronomy and the contributions of Isaac Roberts. But it was not the work that Roberts did at the turn of the century that caught my interest but, another earlier telescope.
The Leviathan of Parsonstown was huge telescope built in Ireland around 1850. From this wikipedia page I not only learn about various types of reflector telescopes, but I learnt about Speculum metal and it’s use in mirrors. The telescope was rebuild in 1997.