conclude from this, that it is the science itself and its foundations that are uncertain”. Of course, said Wargentin, scientists will have different opinions in such a
rapidly evolving science as chemistry.
The following year, Wallerius delivered a lecture in front of the Academy as he
ended his term as president [121]. This lecture can be regarded as a direct attack on
Bergman, Scheele and the circles around them. Wallerius said that he had performed experiments on a daily basis during his 30 years in Uppsala, and had
learned not to accept other chemists’ opinions prematurely, especially not the newer
ideas which were “often only guesses”. Wallerius sought confirmation in experiments, or even better, by observing nature. This was a very important point in
Wallerius’ philosophy.
Wallerius was a strong opponent to analytical chemistry, and he found support in
the works of Boerhaave, Pott and a doctoral dissertation by Daniel Triller published
in Wittenberg in 1767 [122]. The important point in Wallerius’ philosophy was that
analysis did not necessarily reveal the actual composition of a body. He gave two
examples. The precipitation of iron oxides (ochre) and calcium sulphate (gypsum)
upon evaporating mineral water did not mean that these substances were present as
such in the water. The other example was the distillation of ethanol (Spritus vini)
with sulphuric acid to give “a penetrating Liquor mineralis”, “a fine aether” (diethyl
ether), a “sulphur spiritus” (SO 2 ), a “clear heavy oil” (diethyl sulphate), “something
tar-like” and a siliceous earth (SiO 2 ). This could, according to Wallerius only
happen through a complete decomposition and recombination. The siliceous earth
that Wallerius referred to must, of course, have originated from the glassware.
“Here against are a large number of chemists, who live in the conviction within
themselves, that everything that a body, by the action of more or less artificial
solutions, can yield, is a significant part of the body.” These are quite harsh words
from a former professor. The best way, according to Wallerius, was to “ask nature”.
The natural processes occurring within Earth are slow and by studying these processes one could make “absolutely certain conclusions”. Instead of the direct
quantitative measurements of Bergman and others, Wallerius suggested qualitative
conclusions made through analogies with natural processes. First, he discussed
carbon dioxide (fixed air), a subject where he and Bergman had very different ideas.
Bergman (Chap. 18) had shown that carbon dioxide is an acid present in the air,
while Wallerius believed that air contained sulphuric acid. Wallerius said that some
(i.e. Bergman) had suggested that sulphuric acid in the atmosphere would react with
potassium carbonate to give potassium sulphate (which of course is correct).
According to Wallerius, however, one could not expect that such a “fine air-like”
sulphuric acid would behave as ordinary sulphuric acid. Wallerius gave no reasons
for that assumption. He discussed different theories of carbon dioxide, without
naming Bergman, and finally came to the conclusion that carbon dioxide is not an
independent acid. On which grounds he favoured this view is not told, but Wallerius often had a tendency to select examples that fitted his ideas. Then he attacked
Priestley and his use of a eudiometer, a graded glass tube for measuring the changes
in gas volume. Wallerius had misunderstood Priestley’s experiment, but the
important thing is his conclusion: Priestley had
9.6 Bergman’s Relations with Wallerius and von Engeström
143
rapidly evolving science as chemistry.
The following year, Wallerius delivered a lecture in front of the Academy as he
ended his term as president [121]. This lecture can be regarded as a direct attack on
Bergman, Scheele and the circles around them. Wallerius said that he had performed experiments on a daily basis during his 30 years in Uppsala, and had
learned not to accept other chemists’ opinions prematurely, especially not the newer
ideas which were “often only guesses”. Wallerius sought confirmation in experiments, or even better, by observing nature. This was a very important point in
Wallerius’ philosophy.
Wallerius was a strong opponent to analytical chemistry, and he found support in
the works of Boerhaave, Pott and a doctoral dissertation by Daniel Triller published
in Wittenberg in 1767 [122]. The important point in Wallerius’ philosophy was that
analysis did not necessarily reveal the actual composition of a body. He gave two
examples. The precipitation of iron oxides (ochre) and calcium sulphate (gypsum)
upon evaporating mineral water did not mean that these substances were present as
such in the water. The other example was the distillation of ethanol (Spritus vini)
with sulphuric acid to give “a penetrating Liquor mineralis”, “a fine aether” (diethyl
ether), a “sulphur spiritus” (SO 2 ), a “clear heavy oil” (diethyl sulphate), “something
tar-like” and a siliceous earth (SiO 2 ). This could, according to Wallerius only
happen through a complete decomposition and recombination. The siliceous earth
that Wallerius referred to must, of course, have originated from the glassware.
“Here against are a large number of chemists, who live in the conviction within
themselves, that everything that a body, by the action of more or less artificial
solutions, can yield, is a significant part of the body.” These are quite harsh words
from a former professor. The best way, according to Wallerius, was to “ask nature”.
The natural processes occurring within Earth are slow and by studying these processes one could make “absolutely certain conclusions”. Instead of the direct
quantitative measurements of Bergman and others, Wallerius suggested qualitative
conclusions made through analogies with natural processes. First, he discussed
carbon dioxide (fixed air), a subject where he and Bergman had very different ideas.
Bergman (Chap. 18) had shown that carbon dioxide is an acid present in the air,
while Wallerius believed that air contained sulphuric acid. Wallerius said that some
(i.e. Bergman) had suggested that sulphuric acid in the atmosphere would react with
potassium carbonate to give potassium sulphate (which of course is correct).
According to Wallerius, however, one could not expect that such a “fine air-like”
sulphuric acid would behave as ordinary sulphuric acid. Wallerius gave no reasons
for that assumption. He discussed different theories of carbon dioxide, without
naming Bergman, and finally came to the conclusion that carbon dioxide is not an
independent acid. On which grounds he favoured this view is not told, but Wallerius often had a tendency to select examples that fitted his ideas. Then he attacked
Priestley and his use of a eudiometer, a graded glass tube for measuring the changes
in gas volume. Wallerius had misunderstood Priestley’s experiment, but the
important thing is his conclusion: Priestley had
9.6 Bergman’s Relations with Wallerius and von Engeström
143