This Boyle’s machine was made by the British Oxygen Company (BOC) in the 1950’s. The original Boyle's machine was invented by the British anaesthetist, Henry Boyle in 1917. His machine was a modification of the American Gwathmey apparatus of 1912, and became the best known early continuous flow anaesthetic machine. The Boyle’s machine was first made by Coxeter and Sons, under the direction of Lord George Wellesly, which was later acquired by the British Oxygen Company (BOC). Though a lot of changes have been made to the original design of the Boyle’s machine, the basic structure remains the same today.Green trolley on casters with flowmeter and vaporiser bottles attached to a stainless cross bar. There is a glass shelf at top of the trolley and a second glass shelf at base of trolley, above a pull out drawer. The pull out drawer contains 4 x black rubber masks, 3 x black rubber tubing connectors, 4 x seals, 1 a black corrugated rubber hose with red rebreather bag, red tube and masonite support board.Tin plate attached to upper portion of trolley: THE / BOYLE / apparatus / BY THE BRITISH OXYGEN CO. LTD.henry boyle, anaesthetic machine, gas, oxygen, flowmeter, nitrous oxide, british oxygen company, boc, coxeter and sons