There are two statues of very large Angels in the Exploratorium that are survivors of the original statuary that decorated the Palace of Fine Arts during the San Francisco 1915 Panama-Pacific International Exposition. Like all the buildings and ornaments for the Exposition, it was never meant to be permanent. Built of wire and wood, and covered with plaster and burlap-like fiber, these deceptively solid maidens are quite fragile. All the original statuary was either destroyed or sold to raise funds for the 1960 restoration of the Palace. These Angels were used to cast the replicas that decorate the rotunda.