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

The Coxeter-Mushin carbon dioxide absorber consists of the main metal body, painted aquamarine, fixed to a stand. The cylindrical silver metal cannister on the left was used to contain ether, while that on the right contained soda lime. The apparatus has been sectioned to show the inside of the two cannisters, the right of which has an arrow drawn inside to indicate the flow of air breathed out by a patient. The front cover over the control dials has also been removed to show the mechanism. The two circular holes above the dials, facing forward, are where two corrugated tubes would attach; both of these tubes attached to the mask of the patient. The round yellow knob in the centre controls the Compensating Valve, which allowed the anaesthetist to raise or lower the rebreathing bag to allow air into the circuit or expel anaesthetic gas.anaesthesia, carbon dioxide, ether, soda lime