On 11 December 1844 Horace Wells was the first to use the gas nitrous oxide as an inhalational anaesthetic. Wells himself acted as the patient, a fellow dentist extracted a tooth, and Wells felt no pain at all. This marked the beginning of general anaesthesia, without which most of the subsequent developments in surgery would not have been possible. The priority on these findings was heavily disputed between Wells and his former student, William T. Morton, who later, in 1846, introduced ether as another inhalational anaesthetic. To support what seemed to Wells his due right he published a small pamphlet entitled 'History of the Discovery of the Application of Nitrous Oxide Gas, Ether, and Other Vapors, to Surgical Operations' in 1847, a reprint of which serves as the core of 'Horace Wells - On Nitrous Oxide'.