D’une première expérience d’anesthésie chirurgicale au protoxyde d’azote, tentée par Horace Wells le 11 décembre 1844, suivie, le 16 octobre 1846, d’une anesthésie à l’éther sulfurique proposée par William Thomas Green Morton au chirurgien John Collins Warren du Massachusetts Hospital de Boston, on passa à une anesthésie où les mélanges gazeux étaient déterminés à l’avance. Les fabricants d’instruments chirurgicaux œuvrèrent à l’amélioration des matériaux nécessaires à la construction des inhalateurs, tout en imaginant une disposition idéale pour les robinets, les soupapes et les diaphragmes.Improvements to surgical anesthesia thanks to patents, 19th Century. From the first experiment of anesthesia with nitrous oxide, performed by Horace Wells on 11 December 1844, followed by an anesthesia with sulphuric Éther on 16 October 1846, based on the advice of William Thomas Green Morton to the surgeon John Collins Warren at the Massachusetts Hospital in Boston, we moved on to anesthesia where the gas mixtures were determined in advance. Surgical instrument makers worked to improve the materials needed to build inhalers, while designing the ideal layout for the taps, valves and diaphragms. The first European patent for an Éther inhaler was applied for in France on 30 January 1847 by the surgical instrument maker Frédéric J. Benoit Charrière. This model was the source of several instruments and patents. It was only on 3 March 1908 that the French Instrument maker Anatole P. U. Louis Collin invented an Éther inhaler that added expired carbonic acid gas to the mixture inhaled. This device, called the Louis Ombrédanne inhaler, enjoyed unprecedented success throughout the world over the next 40 years.