The 36 inch (91.44-cm) refracting telescope on Mt. Hamilton saw first light on January 3, 1888. It was Earth's largest refracting telescope during the period from when it saw first light until the construction of Yerkes in 1897.
The Lick Observatory is an astronomical observatory, owned and operated by the University of California. It is situated on the summit of Mount Hamilton, in the Diablo Range just east of San Jose, California, USA. The observatory is managed from the University of California, Santa Cruz, where its scientific staff moved in the mid-1960s.
In April, 1888, the observatory became the first permanently occupied mountain-top observatory in the world. Edward Singleton Holden was the first director. The location provided excellent viewing performance due to lack of ambient light and pollution; additionally, the night air at the top of Mt. Hamilton is extremely calm, and the mountain peak is normally above the level of the low cloud cover that is often seen in the San Jose area. When low cloud cover is present below the peak, light pollution is cut to almost nothing.
The observatory was constructed between 1876 and 1887, from a bequest from James Lick.