The development of the anaesthetic vaporizer

Summary The innovatory features incorporated into A.G. Levy's regulating chloroform inhaler, and their contribution to modern vaporizer design, are examined. Levy may be credited with the important realisation that the gas mixture which leaves the vaporizing chamber is fully saturated at all flow rates; with the concept of the splitting ratio; with appreciation of the importance of the application of Reynolds' researches on laminar and turbulent flow to the design of anaesthetic apparatus; and with the provision of a facility to compensate for changes of temperature in the vaporizing chamber.