The Billinghurst Requa Battery gun was an early rapid-fire gun used during the American Civil War. It was invented by a Dr. Josephus Requa (1833–1910), a dentist by profession, who had at the age of 16 spent three years as an apprentice to William Billinghurst (1807–1880). The battery was never officially accepted into service, however it saw action at Fort Sumter and Siege of Petersburg as well as the Battle of Cold Harbor. However advances in firearms technology soon rendered the weapon obsolete.