• 1878 British playwright William Schwenck Gilbert and British composer Arthur Seymour Sullivan complete H. M. S. Pinafore, their second popular comic opera.
• British novelist Thomas Hardy publishes The Return of the Native.
• German scientist Wilhelm Max Wundt (1832-1920) establishes the first laboratory devoted entirely to experimental psychology.
• French scientist Paul Bert conducts research on the deep-sea divers' disease known as "the bends," proving that the often fatal condition may be prevented
  by decreasing air pressure slowly and by degrees. The discovery makes the construction of bridges and underwater tunnels far less hazardous than in the
  past.
  
  
• A Belgian group headed by King Leopold II engages explorer Henry M. Stanley to establish trading stations in the Congo River region, a commission he carries out in 1879-1884.
• 7 Feb.

Pius IX dies after the longest papacy in history, thirty-two years. He is succeeded by Leo XIII (1810-1893).