copper, and he attempted, with great persistence, to persuade Gahn to continue this
work. Gahn was reluctant, as he wanted to continue his studies [6]. Bergman was
aware of Hermelin’s determination, and concluded that nothing could be done to
change his mind. As matters unfolded, Gahn would remain in Falun during his
entire career, but became a very skilled analytical chemist. In particular, he was a
true master of blow pipe analysis (Sect. 23.5). Unlike Scheele and Bergman,
however, he became more and more detached from academic chemistry and, surprisingly, he never published any of his experimental results. This is usually
attributed to his very high expectations on his own work and the fear that his
investigations were not thorough enough; all of Gahn’s discoveries were made
public by his friends. Bergman tried to persuade Gahn to publish, apparently in
order to merit him for a membership in the Royal Swedish Academy of Sciences.
Gahn answered, however, that he had little time for writing. Still, Gahn had a great
reputation in Sweden, and was eventually elected a member of the Academy 1784.
2
At the end of his life, he befriended the young Berzelius, who was very impressed
by Gahn’s experimental skills, and persuaded Gahn to write a chapter on blow-pipe
analysis for his textbook, and some essays for his Afhandlingar i fysik, kemi och
mineralogie (Memoires in Physics, Chemistry and Mineralogy). Gahn married
Anna Maria Bergström in 1784 and the couple had three children. As of 2019,
dozens of descendent of the Gahn family lived in Sweden. Gahn himself passed
away in Falun on December 8, 1818.
There are different versions of how Scheele and Gahn met. One story goes back
to Carl Zetterström, who was hired as a private teacher for the children of Henric
Gahn (1747–1816), physician and younger brother of Johan Gottlieb. In his diary,
Zetterström describes a dinner at Johan Gottlieb Gahn’s place in April 1794. The
guests also included Anders Gustaf Ekeberg (Sect. 11.4.8) and Bergman’s former
student Bengt Reinhold Geijer. An excerpt from the diary reads:
Gottlieb Gahn told how he discovered Scheele at Lokk’s pharmacy, when he asked why it
smelled of nitric acid
3 when Antimonium diaphoreticum [see Sect. 8.2] and Sal acetosellæ
[potassium hydrogen oxalate] where mixed together, then one of the apprentices said: does
not you Gentlemen understand that? Well, it works like this etc. And this pharmacy
apprentice was Scheele. Gahn had difficulties to get him to Bergman, since Scheele had
then already sent something to the Academy of Science in Stockholm [see Sect. 8.2], which
Bergman, by not reading it correctly to the end, had given a negative review. [2]
As described in Sect. 8.2, Scheele had discovered how nitrous acid was liberated
from nitrite in the mother liquor of Antimonium diaphoreticum by week acids. Gahn
reportedly told the story to Bergman, who became curious and wanted to meet
Scheele. A different version of the story is found in Thomson’s History of Chemistry [7]. According to Thomson, who had met Gahn, Lokk had previously asked
Gahn why potassium nitrate (saltpetre) that had been kept molten, gave off red
2
According to preserved protocols, Gahn did not give any inaugural lecture in the Academy. These
lectures had become more and more rare at the end of the century.
3
Zetterström wrote”skedvatten”, which has no direct English translation. The name came from
German, Scheiden, to separate, and alludes to its property to separate silver from gold. “vatten”
means water.
196
13 Scheele in Uppsala
work. Gahn was reluctant, as he wanted to continue his studies [6]. Bergman was
aware of Hermelin’s determination, and concluded that nothing could be done to
change his mind. As matters unfolded, Gahn would remain in Falun during his
entire career, but became a very skilled analytical chemist. In particular, he was a
true master of blow pipe analysis (Sect. 23.5). Unlike Scheele and Bergman,
however, he became more and more detached from academic chemistry and, surprisingly, he never published any of his experimental results. This is usually
attributed to his very high expectations on his own work and the fear that his
investigations were not thorough enough; all of Gahn’s discoveries were made
public by his friends. Bergman tried to persuade Gahn to publish, apparently in
order to merit him for a membership in the Royal Swedish Academy of Sciences.
Gahn answered, however, that he had little time for writing. Still, Gahn had a great
reputation in Sweden, and was eventually elected a member of the Academy 1784.
2
At the end of his life, he befriended the young Berzelius, who was very impressed
by Gahn’s experimental skills, and persuaded Gahn to write a chapter on blow-pipe
analysis for his textbook, and some essays for his Afhandlingar i fysik, kemi och
mineralogie (Memoires in Physics, Chemistry and Mineralogy). Gahn married
Anna Maria Bergström in 1784 and the couple had three children. As of 2019,
dozens of descendent of the Gahn family lived in Sweden. Gahn himself passed
away in Falun on December 8, 1818.
There are different versions of how Scheele and Gahn met. One story goes back
to Carl Zetterström, who was hired as a private teacher for the children of Henric
Gahn (1747–1816), physician and younger brother of Johan Gottlieb. In his diary,
Zetterström describes a dinner at Johan Gottlieb Gahn’s place in April 1794. The
guests also included Anders Gustaf Ekeberg (Sect. 11.4.8) and Bergman’s former
student Bengt Reinhold Geijer. An excerpt from the diary reads:
Gottlieb Gahn told how he discovered Scheele at Lokk’s pharmacy, when he asked why it
smelled of nitric acid
3 when Antimonium diaphoreticum [see Sect. 8.2] and Sal acetosellæ
[potassium hydrogen oxalate] where mixed together, then one of the apprentices said: does
not you Gentlemen understand that? Well, it works like this etc. And this pharmacy
apprentice was Scheele. Gahn had difficulties to get him to Bergman, since Scheele had
then already sent something to the Academy of Science in Stockholm [see Sect. 8.2], which
Bergman, by not reading it correctly to the end, had given a negative review. [2]
As described in Sect. 8.2, Scheele had discovered how nitrous acid was liberated
from nitrite in the mother liquor of Antimonium diaphoreticum by week acids. Gahn
reportedly told the story to Bergman, who became curious and wanted to meet
Scheele. A different version of the story is found in Thomson’s History of Chemistry [7]. According to Thomson, who had met Gahn, Lokk had previously asked
Gahn why potassium nitrate (saltpetre) that had been kept molten, gave off red
2
According to preserved protocols, Gahn did not give any inaugural lecture in the Academy. These
lectures had become more and more rare at the end of the century.
3
Zetterström wrote”skedvatten”, which has no direct English translation. The name came from
German, Scheiden, to separate, and alludes to its property to separate silver from gold. “vatten”
means water.
196
13 Scheele in Uppsala