On October 16th, 1846, Dr. John Collins Warren performed the operation that would become the first successful public demonstration of the use of ether for surgical anesthesia in the operating theatre at the Massachusetts General Hospital. In succeeding years it became an annual custom at the hospital to celebrate October 16th as Ether Day. The commemoration of the event has ranged from pageants and dedication ceremonies to the formal taking of photographs. The above image documents the Ether Day gathering of the 1942 MGH House Officers.