potassium, and ammonium salts in modern terminology. The analogical salts were
regarded as more complex by Bergman. They consisted of a “true salt” and a metal
or earth. An earth was a solid substance that was insoluble in water and which could
not be reduced to metal, i.e. the oxides of calcium, magnesium, aluminium, silicon
and the recently discovered oxide of barium.
Fig. 11.3 The second edition of The Chemical Lectures of H.T. Scheffer appeared in 1779. The
engraved title page was replaced with a simple title page set with types. Photo Anders Lennartson
11.1 Bergman’s Edition of the Chemical Lectures of H.T. Scheffer
163
regarded as more complex by Bergman. They consisted of a “true salt” and a metal
or earth. An earth was a solid substance that was insoluble in water and which could
not be reduced to metal, i.e. the oxides of calcium, magnesium, aluminium, silicon
and the recently discovered oxide of barium.
Fig. 11.3 The second edition of The Chemical Lectures of H.T. Scheffer appeared in 1779. The
engraved title page was replaced with a simple title page set with types. Photo Anders Lennartson
11.1 Bergman’s Edition of the Chemical Lectures of H.T. Scheffer
163