Chloroform

4 November 1847, Queen Street, Edinburgh

On 4 November 1847, the Edinburgh obstetrician James Young Simpson and his assistants George Keith and James Matthews Duncan deliberately inhaled chloroform at Simpson's Queen Street home. It rendered all three unconscious.

Simpson had already used ether in obstetrics but disliked its persistent odour, its irritation of the airway and the amount required. The chemist David Waldie is credited with suggesting chloroform as a substance worth testing.

Four days to the first patient

No obstetric patient received chloroform that night. Simpson's first obstetric administration came on 8 November.

In his account of that case, the mother inhaled from a handkerchief rolled into a funnel — half a teaspoonful to start — and the baby was delivered about 25 minutes after inhalation began. She woke unaware that the birth was over.

What "discovery" covers here

Simpson did not discover the chemical; chloroform had been prepared and characterized in the 1830s. Robert Mortimer Glover had already identified its anaesthetic effect — and its cardiac danger — in animal experiments in 1842.

Simpson's contribution was the human and clinical introduction, made quickly: he reported the narcotic effects to the Medico-Chirurgical Society of Edinburgh on 10 November, and printed accounts followed between 12 and 15 November.

Accounts of the evening differ over who else was present and whether the men ended up beneath the table; the three principal experimenters and their loss of consciousness are well established.