This object consists of a wooden case lined with black leather with 4 metal locks, 2 on the front and one on each side. 2 metal pieces on the exterior of the case acted as valves for the gas cylinder contained inside the case during use. 'No.4' is stamped, in white, on the side and top of the case. The inside contains a large rectangular 'box' in the bottom left-hand corner which has a leather-lined side and a black plastic face. The face has a label reading 'The Minnitt Gas-Air Apparartus Manufactured by the British Oxygen Co.Ltd. London N.18 Serial No.6448' and also a gauge displaying the level of nitrious oxide in the attached gas cylinder. The top-side of the interior box has a thick metal tubing system which attached to the cylinder during use. A hole in the face of the interior 'box' allows the accompanying mask, which has black plastic tubing and a leather mouthpiece, to be attached to the rest of the apparatus. The underside of the case's lid has an attached list of instructions. Also in the case is a small section of plastic tubing, which may have originally being attached to the mouthpiece of the mask.

Notes:  Part of the Leek Nursing Collection. Robert James Minnitt, a Liverpool Medical Practioner, first developed the nitrious oxide gas and air machine used by women as pain relief during child birth. The first Minnitt gas and air machine, often known as a 'Queen Charlotte', was used by a patient at Liverpoool Maternity Hospital on 16 October 1933. Commonly known as 'gas and air', entonox is a mixture of 50% nitrous oxide and 50% oxygen. It can be self-adminstered and if enough is inhaled to begin to induce anaesthesia, the patient becomes unable to hold the valve located on the mouthpiece and so would drop it and exhale the gas. As a result the apparatus does not require the presence of a anaesthetist and so was ideal for easy travelling as part of the 'flying squads' in the 1940s-1960s.