Nitrous oxide cylinder by the British Oxygen Co. Ltd., English, 1939

This gas cylinder contains nitrous oxide or ‘laughing gas’. In the late 1860s, nitrous oxide replaced chloroform as the preferred anaesthetic in dentistry.

In England in 1868, George Barth and J Coxeter, of Coxeter & Son, a surgical and medical supplier, developed a way to turn nitrous oxide from gas to liquid so it could be stored easily in cylinders and sold commercially. The British Oxygen Company began producing nitrous oxide for medical use in 1925, offering a 'Free London Motor Delivery Service.'