HMS Cleopatra 1915. Image courtesy Imperial War Museum.
- The British light cruiser HMS Cleopatra rams the German destroyer SMS G194 in the North Sea, cutting it in half. The destroyer sinks immediately with the loss of 93 lives. The Cleopatra then collides with HMS Undaunted, but manages to return safely to port. Undaunted takes several days to reach safe harbor.
- British seaplanes bomb German airship sheds in Schleswig-Holstein, east of the island of Sylt. Three seaplanes are brought down and five airmen taken prisoner.
- The destroyer HMS Medusa collides with HMS Laverock off the Danish coast whilst under attack by German aircraft. The Medusa sinks; her crew are rescued by HMS Laverock.
- Russian forces gain ground near Jacobstadt in modern-day Latvia
