The Ether Dome is a surgical operating amphitheater in the Bulfinch Building at Massachusetts General Hospital in Boston. It served as the hospital's operating room from its opening in 1821 until 1867. It was the site of the first public demonstration of the use of inhaled ether as a surgical anesthetic on October 16, 1846, otherwise known as Ether Day. Crawford Long, a surgeon in Georgia, had previously administered sulfuric ether in 1842, but this went unpublished until 1849. The Ether Dome event occurred when William Thomas Green Morton, a local dentist, used ether to anesthetize Edward Gilbert Abbott. John Collins Warren, the first dean of Harvard Medical School, then painlessly removed part of a tumor from Abbott's neck. After Warren had finished, and Abbott regained consciousness, Wa