(nitrous oxide)
The effects of breathing nitrous oxide were first investigated by the distinguished chemist Sir Humphry Davy (1778–1829). In Bristol, as a young man, Davy joined the Pneumatic Institute, which was run by Dr Thomas Beddoes (1760–1808). Here experiments were undertaken on the effects of breathing gases. They were frequently dangerous, but were an important step towards the discovery of
anaesthetics. The 'subjects' included some of the most famous men of letters of the day, for example Robert Southey and Samuel Taylor Coleridge, who wrote:
- The first time I inspired the nitrous oxide, I felt a highly pleasurable sensation of warmth over my whole frame, resembling that which I remember once to have experienced after returning from a walk in the snow into a warm room. The only motion which I felt inclined to make, was that of laughing at those who were looking at me.
Davy first tried the experiment on 11 April 1799, when he obtained nitrous oxide in a pure state. He describes a later experiment in these words:
- A thrilling, extending from the chest to the extremities, was almost immediately produced. I felt a sense of tangible extension highly pleasurable in every limb; my visible impressions were dazzling, and apparently magnified, I heard distinctly every sound in the room, and was perfectly aware of my situation. By degrees, as the pleasurable sensations increased, I lost all connection with external things; trains of vivid visible images rapidly passed through my mind, and were connected with words in such a manner, as to produce perceptions perfectly novel. I existed in a world of newly connected and newly modified ideas: I theorized, I imagined that I made discoveries. When I was awakened from this semi-delirious trance by Dr Kinglake, who took the bag from my mouth, indignation and pride were the first feelings produced by the sight of the persons about me. My emotions were enthusiastic and sublime, and for a minute I walked round the room perfectly regardless of what was said to me. As I recovered my former state of mind I felt an inclination to communicate the discoveries I had made during the experiment. I endeavoured to recall the ideas: they were feeble and indistinct; one collection of terms, however, presented itself; and with a most intense belief and prophetic manner, I exclaimed to Dr Kinglake, 'Nothing exists but thoughts! The universe is composed of impressions, ideas, pleasures and pains!' (Kendall 1954: 44–5).
Davy realized that the gas might be useful as an anaesthetic, for he wrote in 1800: 'As nitrous oxide in its extensive operation appears capable of destroying physical pain, it may probably be used with advantage during surgical operations in which no great effusion of blood takes place.' He tried it for toothache, but unfortunately the pain returned worse than before — so he missed a great discovery by not continuing. It was not until 1844 that Horace Wells, an American dentist, first employed nitrous oxide successfully for this purpose — for the extraction of one of his own teeth. (See
anaesthesia.)
(Published 1987)— Richard L. Gregory
Bibliography- Kendall, J. (1954). Humphry Davy, Pilot of Penzance.