he also reports on an investigation of borax (sodium tetraborate, Na 2 B 4 O 7 ). Scheele
isolated boric acid, which was known and used in medicine under the name Sal
sedativum, but it had previously not been noticed that it was, in fact, an acid. Since
borax was imported from India and China, and its origin was virtually unknown and
surrounded by myths, Scheele regarded boric acid as an organic acid. Baumé’s
report that borax could be prepared from lard was disproved by Scheele in 1773.
The studies on nitrous acid and borax were never published. Scheele’s first
attempt to publish his discoveries, probably encouraged by Retzius, was in 1767 or
1768. Scheele wrote a paper on Globuli martiales, which were prepared by boiling
a mixture of iron flings with water and potassium hydrogen tartrate (cream of tartar)
and forming the product into balls, which were dried. These balls were used to
prepare medicines or were added to bath water (iron baths). Retzius claims that the
manuscript was sent to the Royal Swedish Academy of Sciences, although it was
actually never recorded in Stockholm [9]. It is possible that Scheele sent the
manuscript directly to one of the members, most probably to Bergman. Retzius
wrote that the paper contained a large number of experiments, but
without the order, that is present in his latter works, and the concluded theory was so
elaborate, that nothing could be extracted from it without great effort. I know nothing more
than that it came into the hands of Bergman and disappeared. [10]
Bergman may have kept the manuscript (or received a latter version after he
befriended Scheele, as he wrote to his friend Gahn in December 1771:
I now send you some other experiments [by Scheele]. The beginning is the end of a
description of the preparation of Globuli ♂les, which is neither so interesting, nor so short,
that it needs to be attached.
Although the manuscript is lost, a summary has survived among Gahn’s notes
(Sect. 20.2) [11]. This proves that Gahn did not share his notes from his meetings
with Scheele; why would Bergman otherwise send an excerpt to Gahn? This may
be of some importance, as it seems that Bergman was the last of Scheele’s friends to
learn about the discovery of oxygen. If Gahn knew of Scheele’s discovery of
oxygen, he would not necessarily have told Bergman. Among the experiments on
Globuli maritiales, Scheele showed for the first time that hydrogen is evolved when
iron was treated with organic acids.
Nordenskiöld assumed that the paper on Globuli martiales was written before
the report on nitrous acid [12], but Boklund was of another opinion [13]. In his
report on nitrous acid and subsequent letters to Retzius, Scheele stressed that
phlogiston is a principle, and still shares the old views of Stahl. The study on
Globuli martiales, however, forced Scheele to change his view. When he observed
that hydrogen was evolved from iron flings and vegetable acids, he came to the
conclusion, independently of Cavendish, that the evolved gas was phlogiston in an
elastic state. This was a very strong deviation from the view he held in late 1767.
Boklund has also shown how Scheele changed his view once again. In the version
of the Globuli martiales manuscript copied by Gahn in 1770, Scheele describes an
experiment where water acts on iron flings for several weeks. He found that iron
106
8 Scheele in Malmö
isolated boric acid, which was known and used in medicine under the name Sal
sedativum, but it had previously not been noticed that it was, in fact, an acid. Since
borax was imported from India and China, and its origin was virtually unknown and
surrounded by myths, Scheele regarded boric acid as an organic acid. Baumé’s
report that borax could be prepared from lard was disproved by Scheele in 1773.
The studies on nitrous acid and borax were never published. Scheele’s first
attempt to publish his discoveries, probably encouraged by Retzius, was in 1767 or
1768. Scheele wrote a paper on Globuli martiales, which were prepared by boiling
a mixture of iron flings with water and potassium hydrogen tartrate (cream of tartar)
and forming the product into balls, which were dried. These balls were used to
prepare medicines or were added to bath water (iron baths). Retzius claims that the
manuscript was sent to the Royal Swedish Academy of Sciences, although it was
actually never recorded in Stockholm [9]. It is possible that Scheele sent the
manuscript directly to one of the members, most probably to Bergman. Retzius
wrote that the paper contained a large number of experiments, but
without the order, that is present in his latter works, and the concluded theory was so
elaborate, that nothing could be extracted from it without great effort. I know nothing more
than that it came into the hands of Bergman and disappeared. [10]
Bergman may have kept the manuscript (or received a latter version after he
befriended Scheele, as he wrote to his friend Gahn in December 1771:
I now send you some other experiments [by Scheele]. The beginning is the end of a
description of the preparation of Globuli ♂les, which is neither so interesting, nor so short,
that it needs to be attached.
Although the manuscript is lost, a summary has survived among Gahn’s notes
(Sect. 20.2) [11]. This proves that Gahn did not share his notes from his meetings
with Scheele; why would Bergman otherwise send an excerpt to Gahn? This may
be of some importance, as it seems that Bergman was the last of Scheele’s friends to
learn about the discovery of oxygen. If Gahn knew of Scheele’s discovery of
oxygen, he would not necessarily have told Bergman. Among the experiments on
Globuli maritiales, Scheele showed for the first time that hydrogen is evolved when
iron was treated with organic acids.
Nordenskiöld assumed that the paper on Globuli martiales was written before
the report on nitrous acid [12], but Boklund was of another opinion [13]. In his
report on nitrous acid and subsequent letters to Retzius, Scheele stressed that
phlogiston is a principle, and still shares the old views of Stahl. The study on
Globuli martiales, however, forced Scheele to change his view. When he observed
that hydrogen was evolved from iron flings and vegetable acids, he came to the
conclusion, independently of Cavendish, that the evolved gas was phlogiston in an
elastic state. This was a very strong deviation from the view he held in late 1767.
Boklund has also shown how Scheele changed his view once again. In the version
of the Globuli martiales manuscript copied by Gahn in 1770, Scheele describes an
experiment where water acts on iron flings for several weeks. He found that iron
106
8 Scheele in Malmö