As "Titanic" approached her fatal collision, most passengers had gone to bed, and command of the bridge had passed from Second Officer Charles Lightoller to First Officer William Murdoch. Lookouts Frederick Fleet and Reginald Lee were occupying the crow's nest, above the deck. The air temperature had fallen to near freezing, and the ocean was completely calm. Colonel Archibald Gracie, one of the survivors of the disaster, later wrote that "the sea was like glass, so smooth that the stars were clearly reflected." It is now known that such exceptionally calm water is a sign of nearby pack ice.