was discovered by Bernard Courtois in 1811. Courtois, who was born at
Dijon in 1777, was apprenticed to a pharmacist at Auxerre named Fremy,
grandfather of the noted chemist of that name, and was afterwards
associated as assistant with Seguin, Thénard, and Fourcroy. He had
worked with the first-named of these in the isolation of the active
principle of opium, whereby Seguin so nearly secured the glory of
the discovery of the alkaloids. In 1811 Courtois was manufacturing
artificial nitre, and experimenting on the extraction of alkali from
seaweed. He had crystallised soda from some of the mother liquor until
it would yield no more crystals, and then he warmed the liquor in a
vessel to which a little sulphuric acid had been accidentally added.
He was surprised to see beautiful violet vapours disengaged, and from
these scales of a grayish-black colour and of metallic lustre were
deposited.
Courtois was too busy at the time to follow up his discovery, but he
brought it to the notice of a chemist friend named Clement. The latter
presented a report of his experiments to the Academy of Sciences on
November 20th, 1813, two years after Courtois’s first observation. No
suggestion was made by Courtois or Clement of the new substance being
an element.
This deduction became the occasion of an acrimonious dispute between
Gay-Lussac and Humphry Davy. The English chemist happened to be in
Paris (by special favour of Napoleon) at the time when Clement read
his paper. He immediately commenced experimenting, and was apparently
the first to suspect the elementary nature of iodine. His claim
was confirmed by a communication he made to Cuvier. But Gay-Lussac
forestalled his announcement in a paper he read at the Academy on
December 6th, 1813. Davy complained of the trick Gay-Lussac played him,
and Hofer, who investigated the circumstances, came to the conclusion
that Davy was certainly the first to recognise iodine as a simple
_body_, and to give it its name from the Greek, Ion, violet. Ion was
originally Fion, but had lost its initial. The Latin viola was derived
from the original word.
Jean Francois Coindet, of Geneva (an Edinburgh graduate), suspected
that iodine was the active constituent of burnt sponge, which had long
been empirically employed in goitre and scrofula, and having proved
that this was the case, was the first physician to use iodine as a
remedy. The pharmaceutical forms and the medical uses of iodine have
been very numerous during the century which has almost elapsed since
its introduction, but it would be impossible even to detail them here.
Iodoform was first prepared by Serullas about 1828, and its chemical
composition was elucidated by Dumas soon after. It was first used in
medicine by Bouchardat in 1836, and then dropped out of practice for
about twenty years, when it again appeared in French treatises, and its
use soon became general as an antiseptic application.
Bernard Courtois was awarded 6,000 francs by the Academy of Sciences in
1832, but he died in Paris in 1838 in poverty. He had been ruined in
1815 by the competition of East Indian saltpetre with the artificial
nitre which he was manufacturing. In that year the prohibitive duty on
the native product was removed. When the Academy awarded 6,000 francs
to Courtois it also voted 3,000 francs to Coindet, who had so promptly
made medical use of Courtois’ discovery.