Alchemy is the forerunner or even the ancestor of chemistry, and is therefore of historical interest to the student of chemistry, in so far as it can be proved to contain recognizable descriptions of chemical substances, reactions, and technical procedures.
How much may be gained in this respect from alchemical literature is shown by the comprehensive work of E. O. von Lippmann, Entstehung und Ausbreitung der Alchemie (Berlin, 1919).
The peculiar character of this literature lies, however, in the fact that there exists a comparatively large number of treatises from which, apart from
the most superficial allusions, absolutely nothing of a chemical nature can be extracted. It was therefore supposed—and many of the alchemists themselves wanted us to believe—that their mysterious sign-language was nothing but a skillful way of disguising the chemical procedures which lay behind it.
The adept would see through the veil of hieroglyphics and recognize the secret chemical process.
Unfortunately, alchemists of repute destroyed this legend by their admission that they were unable to read the riddle of the Sphinx, complaining that the old authors, like Geber and Raymundus Lullius, wrote too obscurely.
And indeed, a careful study of such treatises, which perhaps form the majority, will reveal nothing of a chemical nature but something which is purely symbolic, i.e., psychological. Alchemical language is not so much semeiotic as symbolic: it does not disguise a known content but suggests an unknown one, or rather, this unknown content suggests itself. This content can only be psychological.
If one analyses these symbolic forms of speech, one comes to the conclusion that archetypal contents of the collective unconscious are being projected.
Consequently, alchemy acquires a new and interesting aspect as a projected psychology of the collective unconscious, and thus ranks in importance with mythology and folklore.
Its symbolism has the closest connections with dream symbolism on the one hand, and the symbolism of religion on the other. ~Carl Jung, CW 18, Page 747