Lick Observatory telescope. 19th-century artwork of astronomers using the Great Lick Refractor, the 36-inch telescope built at the Lick Observatory, Mount Hamilton, California, USA, between 1880 and 1888. The telescope was over 17 metres in length, and more than 40 tons in weight. 36 inches refers to the diameter of the refracting lens, which was, at that time, the largest in the world. The observatory was built at an altitude of 1280 meters and was the world's first permanent mountaintop observatory. The telescope designers and builders were Warner and Swasey. The object glass was from Alvan Clark and Sons. Lithograph published 1889.