Although Philip Ball thinks the apocalyptic visions of Paracelsus may indicate mental illness, whereby I have suggested that the true source of Paracelsus in this case rather is Rupescissa.
We instead underneath will claim that the true source of Paracelsus in this case rather is Rupescissa. As an introduction to the subject as a whole we earlier wrote. Like John of Rupescissa, Paracelsus’ ideas were a mixture of pseudo-science and theology, largely derived from the starry-eyed neo-Platonists of 2nd-century Alexandria.
An investigation in the spiritual and naturalist intellectual traditions, that interacted in the Middle Ages to produce new ways of viewing the world like Paracelsus would also do.
Neither in China nor in the West can scholars approach with certitude the origins of alchemy, but the evidences in China appear to be slightly older. Belief in physical immortality among the Chinese seems to go back to the 8th century BC, and belief in the possibility of attaining it through drugs to the 4th century BC. Furthermore, Arabic alchemy partly Greek seem to have been significantly different. 'Quintessence' of Western Alchemy.
Giving the religiosity at the time, it is not surprising that various readers of Paracelsus wanted to reflect this onto indigenous German/Protestant ‘science,’ founded not upon the ‘papist’ Scholastic tradition but upon the bedrock of Scripture, as pagan wisdom (Plato, Pythagoras, Hermes Trismegistus). Thus for example Quirinus Kuhlmann (1651-1689), whose short life of visions and chiliasm ended on the pyre, applauded the Paracelsian Alchemist (and antiquarian), Athanasius Khunrath’s censure of those “damned souls and teachers of folly” who seek wisdom in Aristotle rather than in the Bible, in Nature and in the ‘mirror’ of their own mind (that is to say, in the divine signatures reflecting an archetypal cosmic order).  Khunrath’s ideas also found admirers in Pietists such as Friedrich Breckling (1629-1711)  and Gottfried Arnold (1660-1714), the latter of whom placed Khunrath in that lineage of ‘true’ Christians – stretching from the ancient Gnostics to the Pietists of his own day – who have always faced persecution at the hands of the Roman church. 
Whilst Khunrath’s Amphitheatrum Sapientiae Aeternae was censured by the Parisian theological faculty in the early years of the Thirty Years War,  and his Quaestiones tres perutiles (1607) was placed on the Index in 1667,  criticism was not limited to the defenders of Catholicism. A Paracelsian himself, but of a more Theological bend, the author of the Rosicrucian manifestos, Johann Valentin Andreae (1586-1654), warned that the paradoxical language of Khunrath and his ilk does not bring happiness to a man.  Likewise, the Lutheran theologian and philologist Johann Konrad Dieterich (1612-1667) recommended Khunrath’s “old wives’ tales and nonsensical superstitions” to the fire in his Antiquitates Biblicae (1671).  Dieterich’s scorn was motivated more by scientific than theological objections, as was that of Jacques Gaffarel (1601-1684), librarian to Cardinal Richelieu, who in his Curiositez inouyes (1629) accused Khunrath of “making war on Nature” with his obscurities. 
But Khunrath continued to be thought of as one of the great German adepts – i.e. possessors of the Philosophers’ Stone – amongst Paracelsians,  and his ideas have undergone sporadic revivals within alchemical, Rosicrucian and theosophical circles. The flurry of reprints of Khunrath’s works which emerged in the late eighteenth century from the Rosicrucian publisher Adam Friedrich Böhme testifies to the popularity of his ideas amongst the Gold- und Rosenkreutz, a Freemasonic grouping which sought to wind back the gains of the Aufklärung with its medievalist nostalgia and alchemical cult.  In fin-de-siècle France the Amphitheatrum Sapientiae Aeternae was translated and disseminated widely in the circles of prominent Hermeticists such as Eliphas Lévi and Gérard Encausse (‘Papus’), and the work continues to fascinate esotericists with its intricate emblems and pansophist amalgam of alchemical, Kabbalistic and pietistic elements. 
For all those distinguishing traits of Khunrath’s alchemy which made it variously the object of scorn and praise through the centuries, we will soon see that the core features of his praxis are largely congruent with other alchemies of early modern Germany, and reflect standard pre-occupations detailed in the alchemical corpus as a whole. In his Vom Hylealischen, das ist, Pri-materialischen Catholischen oder Allgemeinen Natürlichen Chaos, der Naturgemässen Alchymiae und Alchymisten (1597; hereafter simply Vom Chaos), Khunrath tells us that he learnt the secrets of the Art by experience and the grace of God; however, he also read prolifically, and received instruction from a certain learned master of the Kabbalah, who was the first to demonstrate to him the procedures we are to discuss.  The details of Khunrath’s laboratory work can be largely deduced from a little-known but highly revealing manuscript of his, Lux Lucens in Tenebris (“A Shining Light in the Darkness”), which describes the production of a Philosophers’ Stone able to transmute both metals and the human body.
1647 the Paracelsian alchemist Ludwig Combach was busy compiling his Tractatus
aliquot chemici singulares summum philosophorum arcanum continentes, a
collection of alchemical texts from a variety of medieval and early modern
writers such as Petrus Bonus, John Dastin, Bernard of Treviso, Johannes Isaac
Hollandus , Edward Kelley/John Dee; there was one treatise, however, which was
not to find its way into his compendium:
I had to hand a little work written in German by Dr. Heinrich Khunrath of Leipzig, Lux Lucens in Tenebris, a clear introduction and without doubt most useful for beginners, which I deemed to be deserving of the first place amongst these tracts, and for that reason I wanted to translate it into the Latin tongue, so that lovers of chemia might possess it, like some Mercury at a crossroads indicating the right direction.  But I do not know by which circumstance that little book happened to vanish, so it could not be made available for the markets. 
A late sixteenth century German version of the tract in question currently resides at the library of the University of Hamburg;  although Combach thought of it only as an introductory text, it is unique amongst Khunrath’s printed and manuscript works for the insight it grants us into his laboratory praxis, and is all the more revealing for its simplicity. Indeed, it exposes the crucial source material for the alchemical process – what would today be called tetrachloroauric acid – which in other places in Khunrath’s printed works remains veiled in accordance with alchemical custom.
Lux Lucens in Tenebris opens with a prayer of gratitude to God for granting the author insight into the workings of Nature; in this prayer two passages from the book of Daniel and Psalms are paraphrased and fused:
Blessed be the name of the Lord from eternity to eternity, for He has laid the foundations for wisdom and power. He changes time and epochs, He sanctions, installs and overthrows the empires of the world, He gives knowledge to those who have understanding and wisdom to the wise, He reveals that which is deep and hidden, and knows that which lies in dusk and darkness, and the light is with Him.  Lord, the fountain of life is with you, and in your light we are enlightened and see how you have miraculously ordered all that there is through your blessed wisdom.  I thank you, God the Father, I praise you for giving me understanding and power, and for showing me that which I have prayed for. 
These words touch upon the vitalism that pervades Khunrath’s work. In his Vom Chaos Khunrath identifies the light mentioned in Psalms 36.9 as the Light of Nature, which all true practitioners of Christian Kabbalah, divine magic and alchemy have sought both in the liber mundi and within themselves, and which has lent them great power.  In the works of Paracelsus the Light of Nature refers to a principle that constitutes and penetrates Nature, as well as a principle standing ‘behind Nature’ by which the constitution of humans and things in the world is made meaningful.  This dual aspect of the Light of Nature is also to be found in Khunrath’s thought, for the Light of Nature is not only the source of the alchemist’s knowledge and power, but is to be found throughout Creation, from the angels, sunlight and empyrean waters to the creatures and metals of the earth – it is the everlasting spirit of God itself.  The fountain of life mentioned by Khunrath in his prayer had already been transposed from its Biblical context into the alchemical literature in the Middle Ages, where it denotes the life-imparting distillation processes within the alchemist’s vessel, which itself is a microcosm of God’s Creation. 
Khunrath continues in Lux Lucens in Tenebris with a customary condemnation of his godless times, in which the true science of Nature granted by God to humankind has been lost and the wrath of God has been brought down upon society by those who care only for their own selfish goals.  Similar sentiments concerning the loss of the prisca sapientia are to be found in the opening words of the Fama Fraternitatis (1614), although there the restoration of the “spotted and imperfect arts” is said to be well underway.  In both cases it is the Scholastics who are the chief object of scorn; as Khunrath puts it in his Vom Chaos, these servants of the devil follow a “certain heathen master” (i.e. Aristotle) and prefer book-learning to the lessons of the oratory and laboratory. 
Not that all heathens are to be condemned, however: in Khunrath’s eyes, the ‘old philosophers and magi’ amongst the pre-Christian pagans held the wonders of God’s Creation in higher esteem than certain so-called Christians.  Indeed, through their researches into the destruction and rebirth of metals they not only came to recognise the manner in which the human body may similarly be reborn, but also became aware of the existence of the Holy Trinity, the birth of the Saviour from a virgin, the transfiguration of the body of Christ, and his resurrection and return to his Father.  The ascription of such knowledge to the pagans has a long history in Christianity; the late 5th century Theosophia, for example, followed certain of the Church fathers in claiming that the Sybilline oracular prophecies and the wisdom of ancient ‘theologians’ such as Orpheus demonstrated pagan foreknowledge of the coming of Christ,  whilst Pierre Abélard controversially attributed knowledge of the Trinity to Plato.  Although the passion of Christ had been employed since the Middle Ages to figuratively portray the alchemical work,  Khunrath’s innovation here is his suggestion that such mysteries were actually revealed to the ancients through the art of alchemy.
Given that the secrets of alchemy are a gift of God to the pious, Khunrath tells us that they have rightly been hidden in the allegorical writings of the Philosophers, in order that such ‘noble pearls’ are not trodden into the muck by blasphemers or misused for personal gain.  Indeed, those who expose the secrets of the Art bring down divine wrath upon their heads, and deserve a sudden, terrible death at the hand of God.  It is for precisely this reason that Khunrath asks his readers to follow the good example of the adepts and guard his little tract from the unworthy.  At this point we may well ask ourselves who those readers might have been. There is no dedication given at the front of Lux Lucens in Tenebris – only the addition by a second hand of Combach’s aforementioned remarks, and a third hand which adds: “I have seen the Latin manuscript, Köln 1514”. 1594 seems to have been meant here; and these words suggest we may add Köln to Dresden, Hamburg and Krumlov as the towns in which Khunrath is known to have worked.  Whilst secret alchemical manuscripts were not always circulated simply for the good of their recipients – tempting a potential patron often being of equal importance – the lack of dedications in Khunrath’s works generally, no less than the possibility he stemmed from the wealthy Conrad family of Leipzig,  may indicate he had no particular need to advertise his skills.
In any case, appeals to secrecy such as that made in Lux Lucens in Tenebris were taken seriously in the early modern period. In 1597 the pretender to the Swedish throne, Duke Karl (1550-1611), ordered a copy of a manuscript of Heinrich Khunrath by the name of Consilium de Vulcani Magica Fabrefactione Armorum Achillis, in which is described a method for manufacturing magical armour.  It seems that Karl was interested in gaining some technological advantage in the war he had just declared on his nephew, King Sigismund III; the intermediary he used to gain the manuscript was Heinrich Khunrath’s brother, Conrad, who wrote upon the title-page that this “most excellent jewel” has been kept in the utmost secrecy, “and justly remains so concealed”.  That the currency of such secret manuscripts could endure for decades is demonstrated by the fact that Count Jacob Alstein, a physician to both Henry IV of France and Emperor Rudolf II, was still keeping these “highly secret” papers strictly to himself by 1614, and publicly denounced their unauthorised publication in the Heldenschatz (1615) of Johannes Staricius. 
One good reason for Khunrath’s plea to guard the secrecy of his Lux Lucens in Tenebris is the fact that it reveals with all clarity the Ausgangsmaterial (source material) for the alchemical process and the manner of its preparation. Indeed, despite the one-time existence of an apparently lost Latin version of the manuscript, the fact that Lux Lucens in Tenebris appears in none of the bibliographies of Khunrath’s work hitherto compiled suggests that it long circulated only amongst a close circle of Khunrath’s friends and colleagues.
Khunrath begins the practica of his manuscript with a discussion of the “true material of the stone, and how it is acquired.”  The works of the alchemists are replete with this subject, we are told, although they have veiled it with figurative and parabolic words. Nevertheless, we are urged to consider the manner in which humans are born, and to reflect upon an old alchemical axiom: “Each thing is borne and begotten by its like, and that which you sow, the same thing you will reap.”  This axiom is already to be found in the work of the Arabic alchemists (hence Khunrath quotes the assertion of the latinised Arabic Turba Philosophorum that “a man does not proceed from anything other than a man”  ), and stems from an old debate in the literature concerning the possibility of transforming one type of metal into another. Whilst some authors such as the thirteenth century Abu’l-Qsim al-Irq believed that all metals belonged to one species and were distinguished only by ‘accidental’ qualities (in the Aristotelian sense),  others such as Avicenna held that metals were different species of one genus rather than varieties of a single species, and that transmutation was therefore impossible.  This latter position does not exclude the possibility of a ‘multiplication’ of precious metals. We will discover more concerning Khunrath’s approach to metallic transmutation in due course; his purpose here is only to advise us that the Philosophers’ Stone or agent of transmutation – which is a ‘temperate’ body, possessing the four Aristotelian qualities and the two alchemical principles in perfect proportion – must be manufactured from a substance to which it is akin.  Hence the material used for the production of a ‘medicine’ for purifying and transmuting metals is super omnia lucens – that is to say, sol, or the sun ‘shining above all things’. This is “a perfect body, a lord of all stones, a king and master of all others,” which is not destroyed but rather improved by the fire: 
Its complex and nature is temperate, neither too hot nor too cold, neither too moist nor too dry, for it is created out of the most subtle and clear substance of quicksilver and a little pure sulphur,  which as a fixed and clear redness lends the substance of quicksilver its colour. Now if this can be said about the nature of gold, because the Philosophers’ Stone takes away all uncleanliness in both the human body and metals, and purifies and changes them, and [as] no more moderate, temperate and perfect body than Q is to be found, it must also necessarily follow that the Philosophers’ Stone must be made from the material and substance or essence of Q. For every tincture should issue and proceed from that to which it is akin. Nevertheless, this cannot happen without a fitting medium, for its body must be broken in order to bring forth its tincture. 
Given that Khunrath has already warned us of the various shady Decknamen or codenames which the alchemists have employed to conceal their Art from the unworthy,  should we understand his words concerning sol literally as denoting common gold? With regard to the much-debated aurum potabile or ‘potable gold’, a medicine produced from the virtuous kernel lying under the hard ‘husk’ of the king of metals, Khunrath warns his readers not to confuse vulgar gold with the Philosophical variety;  in like manner Count Michael Maier (1568-1622) distinguishes his own potable gold from that of his associate, Francis Anthony, by stating that it is not manufactured from common gold but from Philosophical Gold – which, he cryptically remarks, is only conceivable in the imagination.  In accordance with al-R?z?’s statement that “Saturn is the first gate of the arcana,” for Maier the point of departure for the alchemical process proper was Saturnus, which we may understand as the prima materia.  Reproofs of those who take common gold as their source material are not uncommon in the alchemical canon; perhaps the most elegant and amusing example is to be found in de Limojon’s Le Triomphe Hermetique (1689), where we find a dialogue between personifications of Gold and the Philosophers’ Stone, the latter of whom chides his irritated rival thus:
Why are you not angry with God, and enquire why he has not created in you what is found in me?... you are not the gold, of which the Philosophers write, but the same is concealed within me... there is not one in a hundred that works with me, but all of them seek to complete the Art with you, gold, and your brother mercury. Whereby they have erred, however, and proceeded falsely, it being apparent that all of them bring nothing to effect, but employ their gold in vain, destroy themselves by it, and are reduced to poverty. And this is mostly due to you, sol, who know particularly well that no true gold or silver can be made without me, for I alone have that power. 
De Limojon’s work is based upon a similar dialogue given by an unknown Arabic author in the influential Book of Alums and Salts;  it constitutes a reproof of those alchemists who not only confuse common gold with the Philosophical variety, but also elemental mercury with the Mercury of the Wise.
Nevertheless, Khunrath significantly equates the agent of metallic transmutation with an aurum potabile derived in part from common gold. Although the substance produced in Lux Lucens in Tenebris is described variously as a Tincture or Philosophers’ Stone rather than a potable gold, in his Vom Chaos Khunrath identifies the elixir of the Philosophers with the flowing, waxy, ruby-like ‘stone’ which is the end product of the recipe given in Lux Lucens in Tenebris. Aurum potabile is a synonym of this elixir, Khunrath writes, and it is so called because it is easily dissolved in alcohol.  What is more, Khunrath implies that this substance cannot be made from common gold alone, but must be made from common gold with the help of Philosophical Gold, which is the Sulphur residing together with Mercury (Philosophical Silver) in the universal prima materia (Chaos, Azoth).  These ambiguities illustrate well the way in which “the same words are applied to different things” in alchemical discourse; for not only is the prima materia as a whole also referred to by Khunrath as a Mercury, but we will soon see that he deals with more than one type of prima materia as well. In any case, that Khunrath’s words in Lux Lucens in Tenebris concerning sol as the ‘material of the Art’ refer unambiguously to common gold (or some derivative thereof) is made manifest by the recipe which follows, in which this sol is purified and handled in ways that can only apply to the ‘king of metals’.
The recipe given in Lux Lucens in Tenebris begins by telling the reader to take “fine gold purified to the highest degree by quartation or antimony,” and to dissolve the same in a strong aqua regia until it is crystalline.  Quartation belonged to the standard methods for refining gold in the sixteenth century; one part of gold was alloyed with at least three of silver, and heated in a vessel together with aqua fortis (a nitric acid solution commonly distilled from saltpetre, potash alum and a vitriol), whereupon the silver and impurities dissolved and were poured away.  Likewise, antimony (‘the grey wolf’) was widely used for the same purpose; the two metals were alloyed (the gold being thereby ‘devoured’), and the antimony was driven off by oxidation in a cupel (the rebirth of the ‘king’ from the fire, as shown in the following alchemical emblem). 
Aqua regia (Königswasser), so named for its ability to dissolve the king of metals, was commonly prepared by dissolving one part sal ammoniac (ammonium chloride, NH4Cl) in four of aqua fortis and distilling the solution.  Some earlier texts recommend taking roughly the same proportion of common salt for dissolution in the aqua fortis;  in both cases the resulting yellow mixture of hydrochloric and nitric acids (nitromuriatic acid) gives off highly corrosive nitrosyl chloride fumes, and the alchemists must have learnt to handle the substance with caution after its discovery in late thirteenth century Italy.  In order to dissolve gold, filed gold dust or finely cut gold leaf would be placed with the aqua regia in a vessel of good Venetian glass, which was closed up with waxed cloth to hinder the fumes and heated in a larger container half-filled with sand (the Sandbad or balneum arenae  ) to increase reactivity.  Another commonly described method for dissolving gold, which amounts to the same chemical process, involves the heating of gold leaf together with aqua fortis and common salt.
In contemporary chemical nomenclature the reaction of aqua regia with gold proceeds in two stages: 
Au + HNO3 + 3HCl ? AuCl3+ NO + 2 H2O
Whilst the chemical equilibrium established by treating gold with aqua fortis or nitric acid alone allows only a negligible amount of trivalent gold cations (positively charged ions, Au+++) to form, the generation of chloride ions in aqua regia produces a cascading reaction which leads on to the formation of the stable tetrachloroaurate complex ion:
AuCl3 + Cl- = [AuCl4]-H[AuCl4] or tetrachloroauric acid (commonly described with the generic term ‘gold chloride’) forms the golden-yellow or red crystals which Khunrath found at the bottom of his vessel once he had reduced the solution to an oily ‘phlegm’ and set it aside in a cool place, as he describes.  According to Juncker’s Conspectus Chemiae (1738), such crystals “smell like violets”. 
From this point onwards the ‘translation’ of Khunrath’s work into the terms of the modern chemist becomes more difficult, as his manuscript begins to employ the veiled language which pervades the alchemical canon. Thus Khunrath advises us to take the said crystals, set them in solution and treat them with the aforementioned unnamed ‘medium’:
Make the same crystals into a Mercury by an appropriate putrefaction and by adding a medium, as is known to you, and so you have broken the body of Sol for the first time, and brought it to the proximate prima materia. For it is certain that each thing emerges from that in which it is dissolved. Now gold and all metals can be made into a Mercury, just as they were originally also Mercury. But the conversion of the ashes of the metal into a spirit, that is to say to make a fixed thing volatile, is [a conversion] into a Philosophical Mercury. Likewise, convert the ashes of the king of metals into a spirit, so that it becomes a living Mercury, and so you have the true beginning of this Art: for Mercury is the mother, root and source of all perfect and imperfect metals. And know that alone in this Mercury and in no other [substance] lies the greatest secrets both to cure the human body and also to transmute and purify metals... 
In the alchemical literature, putrefaction usually involves setting the alchemical subject in a warm solution and allowing it to ‘putrefy’ or ‘digest’ by means of a low heat; a particular animating agent is often ‘sown’ into the solution in order to bring the ‘dead’ subject back to life.  However, this putrefaction is described further in Lux Lucens in Tenebris as a ‘sublimation’ – not in the sense of the customary vaporisation and condensation, but rather in the sense of making a subtle, sublime material which is more suitable as a Tincture than its undestroyed, coarse body.  With regard to setting the alchemical subject in solution, tetrachloroauric acid in its crystalline form is highly hygroscopic and dissolves easily in water or alcohol; but exactly what ‘medium’ does Khunrath have in mind to achieve this subtiliziren?
In his Vom Chaos Khunrath supplies us with some clues concerning this substance. How should silver or gold be ‘seeded’ in order that they are born again and fruitfully increased, he asks?  First they must be reduced to their prima materia, he declares, without which process all the alchemist’s work is in vain, and this cannot come about without the Mercury of the Wise, which is a “proto-material water and spirit” or the “universal Mercury of the primordial world.”  We shall reflect upon the significance of these words in the context of Khunrath’s cosmogonic speculation in due course; here it suffices to note that we are dealing with two Mercuries or primae materiae. The first is the prima materia of gold itself, the second a universal prima materia which generates the specific prima materia of gold in its putrefactive solution.  Hence Khunrath’s obscure statement that each thing emerges from that in which it is dissolved, and hence his reminder in Vom Chaos that all metals derive from the universal prima materia or Mercury, and that we must therefore place the ‘kernel’ of the body of gold into its ‘primeval essence’. 
Following the putrefactive reduction of the gold to its prima materia, Khunrath tells us that this Mercury of Gold must be gently heated in the balneum arenae, then repeatedly filtered through leather to remove impurities and sublimated twenty-one times.  These processes form the Vorarbeit of the work; the Nacharbeit proceeds in accordance with the oft-repeated axiom of Morienus Romanus, ignis et azoth tibi sufficiunt (‘fire and Azoth suffice for you’).  Hence the Mercury of Gold is sealed in a glass vessel by fusing the opening (the sigillum Hermetis), and gently heated over a period of some months with a ‘Philosophical fire’ – that is to say, with a fire ignited by the light of the sun with the help of a concave mirror or crystal of beryl.  During this period the white and red colour phases are to be observed.  Once it has attained the viscous quality of wax, it may be poured upon a red-hot silver plate, which will thus be transformed into gold.  Clearly a method for gilding metals is indicated here. 
A procedure which is manifestly the same as that described in Lux Lucens in Tenebris, albeit described exclusively with the use of Decknamen, is to be found in Khunrath’s Vom Chaos. However, whereas the end product of the procedure is described in Khunrath’s manuscript simply as ‘the Stone’ or ‘our (i.e. the Philosophers’) Stone’, in Vom Chaos it is characterised as a Lapis philosophorum specialis et parvus, a lesser and specific Philosophers’ Stone, as opposed to a Lapis philosophorum catholicus et magnus (a great and universal Philosophers’ Stone).  The distinction lies in the fact that the lesser Stone is manufactured from metallic silver or gold; it is able to transmute metals and heal diseases by imparting the special silver or golden virtues (‘silverness’ or ‘goldenness’) which God has given these metals by means of Nature.  The greater Stone, on the other hand, is not derived from metals or minerals, and although both Stones are created via the same spagyrical procedure – a resolution of the subject into the prima materia, and its ‘artifical conjugation’ in more perfect proportion – the greater Stone is able to transmute vast amounts of silver or gold through projection of only a minute portion of the substance.  This distinction between universal and particular agents of transmutation is standard in the early modern literature; the fact, however, that no such distinction is made in the recipe given in Lux Lucens in Tenebris leads one to suspect that the manuscript stems from an earlier phase in the development of Khunrath’s thought, in which he held this Tincture to be the Philosophers’ Stone. Alternatively, it may also suggest that the manuscript was written for a specific reader, who was not only well aware of the distinction but who also knew the identity of the unnamed medium to be added to the tetrachloroauric acid in solution (hence Khunrath’s words “wie dir bewusst”). 
In order to arrive at a reasonable hypothesis concerning this medium’s identity, let us now follow an alchemical via negativa, for in his Vom Chaos Khunrath lists a number of candidate substances which have led would-be adepts astray. Far from being a futile diversion, this process of elimination allows an exploration of diverse procedures involving the manipulation of tetrachloroauric acid in the early modern period, as well as the theory associated with them, and demonstrates the importance of the substance for the alchemy of Khunrath’s day.
Given de Limojon’s avowal that ninety-nine percent of alchemists attempted to complete the Art with common gold and quicksilver (which alloys readily with gold), could Khunrath have been utilising one or another form of common mercury as his mystery ‘medium’? In the Supplementum Secundum to his Physica Subterannea (1675), Johann Joachim Becher describes a very similar procedure to that given in Lux Lucens in Tenebris which employs common mercury. In order to transmute silver, gold must be dissolved in aqua regia and quicksilver added; the liquid is reduced to crystalline form, then dissolved in spirit of vinegar, filtered, purified and thickened to the consistency of molten wax. When this tincture is poured on incandescent silver, be it even the thickness of a thaler, such silver will be transformed into gold. 
Despite having infamously sold the Dutch a method for winning gold from sand,  Becher was in fact quite an innovator in matters of manufacturing and commerce, and also played a minor role in the development of modern chemistry through his influence on Georg Ernst Stahl and the phlogiston theory of combustion.  The Supplementum Secundum was dedicated by Becher to his patron Emperor Leopold I in 1675 – the same year in which he was appointed Hofkammerrath at the imperial court in Vienna, and in which he produced a silver medallion imprinted with the words “Anno 1675 mense Julio Ego J. J. Becher Doctor Hanc unicam argenti finissimi ex plumbo arte alchymica transmutavi” (“In July of the year 1675, I, Dr. J. J. Becher, transmuted this piece of finest silver from lead through the art of alchemy”).  In the Supplementum Secundum we find a recipe for creating silver alongside the aforementioned method for creating gold, although here it is mercury rather than silver which is subject to transmutation. The silver is dissolved in aqua fortis and reduced to crystalline form, then repeatedly dissolved and reduced in spirit of wine or vinegar; eventually a ‘salt of silver’ remains in the liquid which has the power to transform quicksilver.  As in the case of the golden tincture, Becher assures his readers that the customary tests will prove an increase in the initial amount of the precious metal took place during transmutation. 
Whilst the fact that Becher died in penury contradicts this latter claim, both of these recipes demonstrate a central problem of alchemy through the centuries – how does one make a ‘fixed’ (i.e. fire-resistant) substance such as silver or gold subtle or ‘volatile’ (i.e. readily vaporizable), so that it retains its silver or golden properties whilst being able to ‘penetrate’ and transmute lesser metals? The creation of a ‘fixed subtle body’, as both Becher and Khunrath put it, is the subject of many an alchemical emblem portraying the coniunctio oppositorum (conjunction of opposites); traditionally the fixed and volatile aspects of a metal were respectively its Sulphur and Mercury, hence Khunrath’s description of gold as being composed of “the most subtle and clear substance of quicksilver and a little pure sulphur.”  For Becher (drawing upon a theory to be found as early as the 4th century pseudo-Synesius) common mercury is the source material of all metals, which differ in form by virtue of the degree of the mercury’s ‘coction’ or heating in the earth.  Porosity and penetration are the key concepts of Becher’s transmutation theory, as metals cannot be tinged like molten glass in the furnace because mercury is ‘compact’ and ‘heavy’ rather than porous. Nevertheless, despite being impenetrable itself, mercury has the power to penetrate other objects; and as penetration is the “principle of every transmutation,” in order to penetrate the compact ‘skin’ of a metal, gold or silver themselves must be made subtle or ‘mercurified’ and given to the lesser metal.  Such penetration is to be distinguished from alloying, which according to Becher is a mere ‘juxtaposition’ of metals, and achieves no net increase in either silver or gold.
For all the similarities between Becher’s procedure for creating a golden tincture and that given in Lux Lucens in Tenebris – i.e. the addition of a prima materia to tetrachloroauric acid, the subsequent filtration and sublimation, the production of a flowing, waxy substance to be poured over incandescent silver – there is little doubt that Khunrath did not use common mercury to create a ‘fixed subtle body’ of gold. He makes this point clear in Lux Lucens in Tenebris, and mounts quite a polemic on the subject in his Vom Chaos.  Quoting from the Rosarium Philosophorum and a letter of Arnoldus de Villanova to the king of Naples, Khunrath states that all true Philosophers “unanimously condemn and damn quicksilver” as the key to the Art.  He notes, however, that a good many Arg-chymisten (wicked-chymists) utilise common mercury, which like the devil disguised as an angel of light brings nothing but injury. 
Whilst it therefore seems likely Khunrath did not utilise common mercury in his work, in Lux Lucens in Tenebris he does make an interesting comparison between his medicine and a common mercurial preparation of his time – mercurius praecipitatus:
As soon as you have such a Mercury of the Sun, then believe with certainty that in a short time and with little trouble you will be able to make such a medicine for renewing and restoring the human body, that no disease – whichever it might be – may resist it, save those that have been inflicted upon a person by divine Providence as a punishment for sin. Which you may understand in part [by comparison with] the Mercury Precipitate which is made from raw [common] mercury with aqua fortis. For if raw mercury, which possesses corrosive properties after precipitation, can achieve so much in several diseases, what power and force do you think this Mercury of the Sun has, which does not work with corrosive properties? 
The mercurius praecipitatus in question is mercuric oxide (HgO), the ‘angel powder’ first described by Niccolò Massa in his De morbo gallico liber (1507); it has cauterising antiseptic properties, and is produced by pouring aqua fortis onto common mercury (brown, highly toxic nitrogen dioxide fumes evolve) and heating the resultant greenish mercury nitrate solution until a dry red precipitate is formed. Massa recommended this caustic substance for eating away the ‘soft, superfluous flesh’ of genital sores caused by syphilis (known to Italians as morbus gallicus, but to the French as le mal de Naples). 
The purpose of Khunrath’s comparison is twofold. Firstly, he wishes to emphasise the ability of gold to impart its temperance to the human body, an ability which is not possessed by lesser metals; what is more, by contrast to mercurius praecipitatus, Mercury of Gold is not caustic, so it can be taken internally to seek out ‘metallic’ diseases such as leprosy and clean the blood.  This latter fact suggests that the purpose of filtering and repeatedly sublimating the Mercury of Gold was to dulcify the substance, i.e. to remove its acidity. Despite the differing theoretical approaches adopted by Becher and Khunrath, the importance of the concept of ‘penetration’ is evident in the work of both men. Hence Khunrath writes that, in order to create a tincture with the power to penetrate metallic and human bodies alike, one must first understand the ‘special method’ by which gold is dissolved and transformed into a ‘spiritual body’.  For it is not plausible that gold can be applied medically in its coarse, undissolved state; and its dissolution into Mercury of Gold can be effected only by the Universal Mercury, the quinta essentia of which Pythagoras speaks, which has the power to transmute metallic bodies into a spirit. 
Following its first manufacture, aqua regia seems to have been hailed by some medieval alchemists as the Universal Mercury itself, although the fact that gold is easily retrievable from tetrachloroauric acid must have worked against the popularity of the idea. Thus in his Vom Chaos Khunrath makes a distinction between metals that have been “radically and internally dissolved” and those that have merely been “macerated and strewn about in very subtle parts” by the use of powerful acids. 
The debate concerning the possibility of irreversibly dissolving gold by separating out its component principles occupied a prominent position in that critical period for the emergence of modern chemistry with which we are dealing, and as we shall see, its echoes continued to reverberate until the early twentieth century. At the centre of the controversy in the early modern period stood Robert Boyle, who in The Sceptical Chymist (1661) makes mention of Mercury of Gold, explaining that “Gold is, of all Metalls, that whose Mercury Chymists have most endeavoured to extract, and which they do the most brag they have extracted.”  As an opponent of the Paracelsian tria prima, Boyle devotes much space to denying the ability to break down any metal to a constituent Mercury (the principle of fluidity, penetrativity and lustre), Sulphur (the principle of combustion and colour) or Salt (the principle of solidity and form), be it with strong acids or fire, and ascribes any apparent success in manufacturing Mercury of Gold to trickery.  It should be noted that, whilst he was no doubt eager to press his revision of Boyle’s legacy, there is little evidence for Principe’s assertion that the said comments in The Sceptical Chymist are directed solely towards the Paracelsian tria prima, and not towards the traditional Sulphur-Mercury dyad; 
for immediately after rhetorically acquiescing to the possibility that Sulphur and a ‘running Mercury’ may be extracted from gold but not a Salt,  Boyle rejects the very same proposition via the words of the ‘impartial judge’ Eleutherius. 
In any case, an opponent of Boyle in this important seventeenth century debate was Andreas Cassius, a physician of Hamburg who was influenced by the atomism of Daniel Sennert, and who leant his name to the dye known as Purple of Cassius (a subject to which we will soon return). In his De Auro (1665) Cassius describes a number of ways of producing aurum potabile – a synonym for Mercury of Gold in his eyes – which involve removing from gold its Salt and Sulphur in order that it is able to penetrate and transmute metals and humans. In accordance with alchemical tradition, Cassius details two methods for achieving this goal: a wet and a dry. The dry method – by fire alone – was used by Moses to produce the ‘potable gold’ he made of the golden calf and gave to the Israelites to drink.  This alchemical interpretation of Exodus 32.20 was also made by Artephius and Basil Valentine; Cassius tells us that although Moses’ deed was not a miracle, the technique he used has been lost. However, the ‘wet’ method is still known to the alchemists: for they dissolve two ounces of verdigris (copper acetate, Cu(C2H3O2)2·H2O, prepared by corroding copper with vinegar) in distilled vinegar, and give the solution to two drachmas of gold dissolved in aqua regia. When this concoction is allowed to sit in a vessel with springwater for a number of days, “there will appear filaments like silk threads dispersed throughout the liquor, and the gold will gradually precipitate and fall to the bottom of the vessel in the most tiny atoms of beautiful golden splendor.” 
Verdigris has been associated with the alchemical Green Lion, which Khunrath uses as another synonym for the animating alchemical agent alongside ‘the green Duenech’ (from the allegory concerning the rejuvenation of the melancholy duke Duenech).  The symbol probably derives from observations of the action of dilute acids upon copper, for according to Wiedemann the Green Lion was a codename for copper amongst the Arabic alchemists. 
Nevertheless, it does not have this connotation in the work of Khunrath, who consistently rejects any talk of metallic acetates or metallic sulfates as possible candidates for the Universal Mercury. For example, he speaks of the Green Lion as ‘our Vitriol’, at the same time telling his readers that “the ordinary copperas (green vitriol, iron (II) sulfate) has nothing to do with it.” Rather, this “universal green lion of Nature” is Visitabis Interiora Terrae Rectificando Invenies Occultum Lapidem Universa Medicinae (“[if] you visit the interior of the purified earth, you will find the secret universal stone of the Medicine”). 
Cassius also describes the manufacture of an aurum potabile by adding a certain mercurius sublimatus rather than verdigris to tetrachloroauric acid.  Whilst these procedures may have resulted in the production of a gold that was more or less potable, it clearly was not what Khunrath had in mind when writing his Lux Lucens in Tenebris. Indeed, Khunrath clearly voices his contempt for those who identify Philosophical Mercury with the ‘innermost essence’ of common mercury, and claim (in accordance with the description of Sendivogius) that such an essence flows as clear as tears in the hands, and yet does not make them wet.  According to Khunrath, this would-be Mercury of the Wise is manufactured by the Arg-chymisten from the aforementioned mercurius sublimatus, known today as mercuric chloride (HgCl2), a strong poison produced by sublimating (i.e. repeatedly vapourising and condensing) mercury nitrate or mercury sulfate mixed with sodium chloride. 
Even if Khunrath rejected the use of mercurius sublimatus in the alchemical work, there were other alchemists in his native Saxony who manipulated tetrachloroauric acid with mercuric chloride to radically ‘dissolve’ gold and thereby create an alchemical tincture. They included Sebald Schwaertzer and David Beuther, who laboured together in the years 1580-1591 to produce a Philosophers’ Stone for the Electors August (1526-1586) and Christian I (1560-1591) of Saxony.  Christian’s wife Sophie von Brandenburg (1568-1622) became Elector after her husband’s death; and the fact that Conrad Khunrath dedicated his Vier Schöne Medicische Tractat (1597) to her may also point to the circles in which his brother Heinrich moved whilst he was in Leipzig and Magdeburg. The harsh words Heinrich directed towards Thomas Erastus, the prominent Calvinist theologian, are at least congruent with the campaign waged against crypto-Calvinism in Saxony by Elector Sophie.
Schwaertzer’s description begins with a formula for producing aqua regia from saltpeter, a vitriol and sal ammoniac, in which four marks of fine gold should be dissolved. This ‘water of gold’ should be evaporated until it runs like oil or ‘thick blood’, and poured into a vessel together with two pounds of an oleo mercurii distilled from mercurius sublimatus, sal ammoniac, saltpeter and alum. The mixture should be sealed in the vessel and placed on a gentle heat for forty days (the putrefaction), then distilled with a retort until a milky white distillate appears (the white phase). This distillate is the body of the Gold made spiritual, devoid of impurities. Dulcification (removal of acidity) proceeds through solution of the distillate in springwater (the ‘washing’ phase), whereupon a white precipitate forms at the bottom of the vessel. The precipitate is useful for healing wounds, Schwaertzer advises us, but has no further use in this particular work. Rather, it is the now yellowish springwater which should be further distilled, and this repeatedly with the addition of more water, and then sublimated until “you find a colour which will make you beside yourself with joy, for nothing is more beautiful. This I have seen with my own eyes,” Schwaertzer continues, “and made with my own hands.” The said colour is red, and thus completes the traditional colour phases of the alchemical process: black, white, yellow and red. 
Apart from producing a tincture for his royal patron which transmuted metals by a factor of 1024, it was Schwaertzer’s burden to show with his experiment that gold may be dissolved into its constituent components, Salt, Sulphur and Mercury, in such a way that no gold could be reconstituted should one of the components be missing. Hence the white precipitate (Sulphur or Terra Q) could no longer yield gold without being joined once again with the metal’s Mercury and Salt. 
Despite Schwaertzer’s somewhat confused juxtaposition of colours and principles, his experiment was cited in the early eighteenth century by a late proponent of transmutation, the chemist Johann Kunckel von Löwenstern, as proof that one may “divide the parts of gold so that in all eternity it will never be gold again.”  With his prodigious knowledge of both alchemy and glassmaking – arts which had stood in close proximity since the Middle Ages – Kunckel attempted to disprove the corpuscularianism of Descartes with recourse to the example of ruby glass, a luxury item deriving its colour from the aforementioned Purple of Cassius. It was Cassius who first uncovered what had been a closely-kept alchemical secret  – the reduction of an aqueous tetrachloroauric acid solution with tin dichloride to produce a powerful pigment.  When he attempted to introduce the pigment into glass, however, the product was merely clear rather than red. Around the year 1679 Kunckel first discovered that the glass must be cooled and gently reheated to obtain the long sought-after colour; according to his description in the Collegium Physico-Chymicum (1716), the pigment consisted of “such subtle atoms of gold, that 1 part can tinge 1280 parts of really beautiful ruby glass.”  He went on to argue that the clearness of the glass prior to reheating was proof that the atomi solares had been ‘vitrified’ and thus thoroughly destroyed, and that consequently no gold could be retrieved from ruby glass.  This he took as a repudiation of mechanistic corpuscularianism; for the principle of Salt in both the gold and the glass had clearly melted together, the gold had thus irretrievably lost its Aristotelian ‘form’, and had been converted into a weightless, non-corpuscular spiritual essence able to penetrate and colour glass. 
Unfortunately for Kunckel, an embittered one-time laboratory technician by the name of Christoph Grummet countered his claim with the dubious assertion that ruby glass gives up fine gold dust when subjected to strong heat; in accordance with Grummet’s prophecy that he would “precipitate with Icarus,” Kunckel subsequently fell from favour at the Saxon court.  Nevertheless, it became widely evident that ruby glass does not appear to yield gold upon melting – a fact observed, for example, by pillagers in the French Revolution – and Kunckel’s observations remained a point of contention until the turn of the twentieth century.  Given that this phenomenon baffled researchers for so long, and that it was so liable to create the impression of gold’s radical dissolution, it behoves us to turn to a particular subset of procedures involving the manipulation of tetrachloroauric acid – the production of gold colloids, a class of products to which ruby glass itself belongs.
It was Richard Zsigmondy (1865-1929) who first solved the problem which had vexed Kunckel and his successors. Inspired by his early employment at a glassworks and with the ultramicroscope he had invented at hand, Zsigmondy was able to determine that ruby glass contains dispersed submicroscopic clusters of gold atoms in such small quantities that their retrieval is indeed problematic.  What is more, both Zsigmondy and his fellow Nobel laureate, The Svedberg (1884-1971), were moved by their research on colloids (dispersed nanoparticles) to suggest that the aurum potabile of Paracelsus and Basil Valentine was a preparation of gold nanoparticles in a fluid dispersion medium (i.e. a gold sol).  Taking a leaf from Cassius’ book, Svedberg suggested that the Paracelsian and Valentinian aurum potabile was derived from the addition of tin dichloride to tetrachloroauric acid in solution,  although there exist a number of other reactants that give rise to colourful gold sols using the same process, with resulting spheroidal clusters of gold atoms usually ranging from 2 to 150 nanometers in size. 
Today gold sols are used chiefly for ‘labelling’ or dying proteins in order to view cellular and tissue components by electron microscopy; the finest nanoparticles (< 5nm) are produced by reduction of a 1% aqueous solution of tetrachloroauric acid with phosphorus in diethyl ether.  The use of phosphorus as a reductive reagent gives rise to a crimson-coloured sol, a procedure which was first described by the pioneering Elizabeth Fulhame in her Essay on Combustion (1794), in which she documented her attempts to make “cloths of gold, silver, and other metals, by chymical processes.”  Fulhame was particularly fascinated by the action of the sun upon cloth impregnated with a tetrachloroauric acid solution:
One exposes a piece of silk which has been dipped in a solution of nitromuriatic gold in distilled water to the rays of the sun, and dampens it with water; the yellow tint which the metallic solution gives to the silk changes to a pale green, and then becomes purple. 
Fulhame correctly inferred that this process was driven by the ‘decomposition’ of the water, as the reductive reagent here is hydrogen released by evaporation.  The minute size of the gold particles produced by such reduction had already been remarked upon by Juncker in his Conspectus Chemiae, who followed Cassius by introducing tin dichloride to a “single drop of dissolved gold in quite some Lote of water” – that the entire solution was permeated by redness was the “clearest proof of how immensely small the particles must be.” 
Svedberg and Zsigmondy were not the first writers to identify colloidal gold with aurum potabile, even if they were amongst the first to fully understand its chemistry in modern terms. In his Dictionnaire De Chymie (1766) Peter Macquer describes those alchemists who dissolve gold with Königswasser, add ethereal oils, separate the latter from the acid and mix them with alcohol; in so doing these ‘charlatans’ claim not only to have ‘fundamentally’ dissolved the gold, but also to have produced a medicine with remarkable healing properties:
In any case, all these gold tinctures are nothing other than natural gold, most finely dispersed and floating about in an oily fluid. Strictly speaking, therefore, they are not tinctures... and they deserve the title ‘potable gold’ only insofar as we do not associate this name with any other concept than gold which floats in a fluid, and which has been made into such fine particles that it is possible to drink in the form of a fluid. 
Following Macquer, in the early twentieth century Vanino experimented with the production of gold sols using various ethereal oils such as the rosemary oil mentioned in the Dictionnaire De Chymie, and came to the conclusion that aurum potabile “must without doubt be counted amongst the predecessors of colloidal gold.” 
How do these various methods for the production of gold sols compare with the processes described by Khunrath in his Lux Lucens in Tenebris? Clearly one of the most remarkable impressions liable to be imparted during the manufacture of colloidal gold is that the metal has been entirely ‘dissolved’; this stands in contrast to those aforementioned varieties of Tincture and aurum potabile produced with verdigris or mercuric chloride, in which “atoms of golden splendour,” albeit minute, are still visible. It must also be said that the brilliant red colours associated with the Philosophers’ Stone through the centuries (“radiant like the sun, clearer than a carbuncle,” as Khunrath describes his flowing ‘Stone’  ) are highly suggestive not only of the presence of gold in alchemical procedures, but specifically the presence of colloidal gold, a fact which inspired Ganzenmüller’s investigations into the alchemical production of ruby glass.
Even the colour phases involved in the manufacture of some gold sols are reminiscent of alchemical process – for example, in 1821 Krüger experimented with the introduction of albumen into an aqueous tetrachloroauric acid solution, and described the ensuing formation of white and red colour phases over a period of six days.  With regard to the waxy consistency of Khunrath’s Philosophers’ Stone, the viscosity of some varieties of aurum potabile has been attributed to the presence of impurities in the synthesising liquids, which form an adsorption layer around gold colloids.  As Khunrath seems to be detailing a method of gilding, it is also quite possible that a gold sol, when poured upon incandescent silver, would lend that metal a golden colour.  Whatever the case may be, it seems likely that at least the Vorarbeit of Khunrath’s procedure – the preparation of Mercury of Gold – involved the production of a colloid, given the impression conveyed by the procedure that the metal had been radically dissolved, and given the fact that the substance could be filtered through leather and retain its gold content. This suspicion becomes ever stronger as we return to consider the identity of Khunrath’s unnamed medium – the Universal Mercury – with recourse to his descriptions of its physical properties.
From certain comments in Khunrath’s Amphitheatrum, we may gather that the Universal Mercury is a highly flammable substance. In various places in his work it is also described as alcohol vini or spiritus vini, which naturally raises the possibility that we are dealing with the distillation of ethanol, given the enthusiasm shown amongst the medieval alchemists for the quinta essentia which was regularly manufactured in their reflux stills.  Indeed, alcohol or ethanol is a suitable reductive reagent for producing an aurum potabile containing colloidal gold – by way of contrast with those varieties of trinkbares Gold, still to be found on the market in Germany, which only possess finely cut Goldblätter suspended in spirits. We also find in the work of both Kunckel and Becher recipes for ‘mercurifying’ gold by adding alcohol to tetrachloroauric acid in solution (and Kunckel reminds his readers that should the vessel break during this sublimation an untimely death may ensue). 
It should come as no surprise, however, that spiritus vini was deployed as a codename by Khunrath, and that with his typically pious style he spots those inebriated ‘adepts’ who work diligently with their alcohol both day and night.  The Universal Mercury does not derive from grains, or apples, or pears – indeed, by Khunrath’s estimation it belongs neither to the realm of minerals, nor to that of animals, and nor to that of vegetables.  This might suggest that the substance of which he spoke was a mere fantasy; nevertheless, his words here merely conform to the alchemical trope of a power preceding and animating all organic and inorganic forms, for which reason the Philosophers’ Stone itself is also described in the corpus as being simultaneously animal, vegetable and mineral.
If we continue with our assumption that the substances with which Khunrath worked are known to contemporary science, then the property of flammability narrows our search field considerably. Moreover, when we consider the fact that Khunrath admits in one place he has smelt and tasted the Universal Mercury himself, and that in another he claims it is “the sweetest smelling substance,”  and in yet another that it is extremely light and ‘hot’ on the tongue, and that it is volatile to the point that it readily evaporates without the application of heat,  then we are driven to conjecture that he was working with diethyl ether (C4H10O), known commonly simply as ‘ether’.
Michael Faraday (1791-1857) was the first to document (with the terms of modern chemistry) the production of a ruby-red gold colloid using diethyl ether and tetrachloroauric acid.  Nevertheless, the late sixteenth century author writing under the name of Basil Valentine speaks of taking the Sulphur from gold and making the metal ‘spiritual’ by means of a substance which is “subtle, penetrating, with a lovely taste and beautiful scent.”  This substance is distilled from oil of vitriol (sulphuric acid) and spiritus vini (ethanol) – a fairly clear indication that the production of diethyl ether was known to him. What is more, the goal of his process was to create an aurum potabile – a fact which led Claus Priesner to remark suggestively that “a colloidal gold-in-ether solution can be prepared by extracting gold containing aqua regia with ether.”  Likewise, in the eighteenth century Macquer spoke of diethyl ether as “one of the best mediums for making a so-called potable gold.” 
The first firm evidence for the production of diethyl ether comes in the work of Paracelsus, who in his Von den Natürlichen Dingen (c. 1525) speaks of a ‘sweet’ substance known to the alchemists and distilled from vitriol and spiritus vini, which has the power to anaesthetise patients without any harmful side-effects.  It has been suggested that the Alkahest or universal solvent of Paracelsus was also diethyl ether, prepared by distillation of ethanol with caustic potash (potassium hydroxide).  Be this as it may, diethyl ether is commonly considered to have entered the realms of modern chemistry in the 1730 transactions of the Royal Society, where Sigismond Augustus Frobenius  described the remarkable properties of his Æthereal Liquor or spiritus vini aethereus, “the lightest of all fluids.” As a solvent for vegetable, animal and mineral products alike, Frobenius described ether as “certainly the most noble, efficacious and useful Instrument in all Chymistry and Pharmacy.”  Even if it is “kindled in a thousand Times the Quantity of cold Water, it burns inextinguishably,”  and is thus “the very Ens, or Being most pure of Flame.”  Noteworthy are the words of Frobenius concerning its use in the dulcification and purification of gold in the form of tetrachloroauric acid:
And indeed a wonderful Harmony is observable betwixt Gold and this Aether... If a Piece of Gold be dissolved in the best Aq. Regia, and upon the Solution Cold, be poured half an Ounce, or what Quantity you please of the Æthereal Liquor, shake the Glass carefully, and all the Gold will pass into the Æthereal Liquor, and the P Regia, robbed of all its Gold, will presently deposite the Copper at the bottom of the Vessel as a white Powder, which turning of a green Colour, contains the Portion of Copper wherewith the Gold was adulterated. The Æther will swim like Oil on the Surface of the corrosive Waters. The Experiment deserves the utmost Attention; for here the heaviest of all Bodies, Gold, is attracted by this very light Æther... owing to a certain Harmony and Similitude of both of them. 
Given the Hermetic flavour of Frobenius’ words concerning harmony and similitude, one may ask in what sense his account is ‘modern’. One answer to this question lies in the fact that it displays the eschewal of secrecy and invitation to experimental verification characteristic not only of the transactions of the Royal Society but also of chemistry as we know it today. True, Frobenius chose to withhold the secret of his ether’s manufacture, and the editor of the Philosophical Transactions advises the reader to contact the author directly if a sample is desired. However, following the death of Frobenius the secretary of the Royal Society, Cromwell Mortimer, published those unreleased portions of the papers submitted by the author, in which are mentioned the efforts of Boyle and Newton to synthesise the same substance.  Of particular note is the fact that Frobenius speaks in these unpublished fragments of a class of four “simple æthereal spirits” corresponding to the earth, the sea, the air and the heavens; whilst the first three are manufactured from salts, the fourth appears to be spiritus vini aethereus itself.  Noteworthy too is Mortimer’s comment that Frobenius had gained all his knowledge concerning the substance from an unnamed noble in Vienna.  If alchemists as prominent and influential as Heinrich Khunrath and Basil Valentine were indeed working with diethyl ether, then these two facts cast some etymological light upon Frobenius’ choice of the nomenclature spiritus vini aethereus (as opposed to Cordus’ ‘sweet vitriol’ or Paracelsus’ spiritus vitrioli). Rather than being an attempt “to hide a substance, perhaps already known to some people, behind a new name,” as Priesner suggests,  the possibility exists that Frobenius actually followed those of his alchemical predecessors who identified diethyl ether with that pure, shining heavenly element known to the Greeks as ákèçñ or ether (from ákèù, to ignite), and characterised by Aristotle as the fifth element, the quinta essentia pervading the superlunary spheres and comprising the heavenly bodies.  For Khunrath names this more ancient ether spiritus aethereus or “the most sweet-smelling ethereal fertility,” and asserts not only that it may be isolated in the laboratory, but also that it is synonymous with the Mercury of the Philosophers with which the Philosophers’ Stone is to be made (i.e. synonymous with diethyl ether, if our conjecture is correct).
Regardless of the truth of this conjecture, the discrepancy between contemporary and traditional connotations of the word ‘ether’ displays another important distinction between the worldviews of alchemy and modern chemistry – the cosmological significance of chemical substances has radically changed. In their rush to join the postmodern critique of all ‘grand narratives,’ Newman and Principe have recently counterposed a “correct chemical analysis” of alchemical texts carried out by “serious historians of alchemy” with a Jungian “analysis of unreason,” and have stated that there is “no indication that the vast majority of alchemists were working on anything other than material substances towards material goals.”  It is necessary to distance the ‘translation’ that has been attempted here from such assertions, as they display precisely the presentism and positivism Newman and Principe claim to disown, by which contemporary cosmologies and notions of matter are unconsciously elevated to the realm of the definitive. Nowhere is this error more clearly demonstrated than in Principe’s The Aspiring Adept, where Paracelsian cosmologies are condemned as “lofty and obscure,” “bizarre and rambling,” “extravagant and incoherent,” and even “pretentious” – which adjectives are counterposed with a positively-valued “recitation of recipes.”  It may well be that Khunrath, who is commonly counted amongst the most mystical and obscure practitioners of the Art, busied himself with procedures that appear relatively mundane to the contemporary chemist; nevertheless, this fact does not help us towards an understanding of the nature of matter itself in the alchemist’s worldview, any more than a description of a Gothic cathedral in terms of the chemical composition of stone and glass would help us to a deeper appreciation of the medieval psyche.
In order to come to a closer understanding of Khunrath’s alchemy, and in particular of that substance which he names alternately ‘ether’, the universal prima materia and the Mercury of the Wise, let us turn again to his Amphitheatrum Sapientiae Aeternae, which counts amongst the most powerful of early theosophical works. An extended commentary on the biblical book of Proverbs and the apocryphal Wisdom of Solomon, the Amphitheatrum presents us with a synthesis of the Christian Neoplatonic and ancient Hebrew cosmologies which is coloured by Kabbalistic and alchemical notions.  His comments upon the substance pervading the divine, supercelestial realm specify a distinctive ‘theosophical’ mode of perception reliant upon celestial influence and divine guidance:
Of what kind, substance and nature the waters above the heavens are must be researched theosophically. I say, therefore, under the direction and guidance of the influence, light and movement of the divine sun, and in the name of God, that the waters above the heavens are of exactly the same kind and substance as that ethereal fluid which burnt without being extinguished, which in the time of our fathers was found in a most ancient grave in Padua, Italy, within which were two vessels held within a clay urn, one of which was gold and the other silver. This lamp burnt on for many years due to the power of this very fine liquor... 
Khunrath’s inspired and revelatory style is evident here, as is the solar mysticism which pervades the alchemical corpus.  This report was drawn by Khunrath from the work of Peter Apian and Bartholomeus Amantius on the inscriptions of antique tombs;  the Roman grave in question belonged to a certain Olybius, and we are told that the everburning lights therein were extinguished when they were exposed to the air by the peasant who unearthed them. 
The conception of such everburning lights is ancient, and is to be found elsewhere in the alchemical and esoteric literature; for example, the tomb of Christian Rosenkreutz was said by Johann Valentin Andreae to be lit with ‘another sun’ at its ceiling,  whilst Bartholomäus Korndörffer’s Everburning Lights of Trithemius (late 16th century) describes the manufacture of a little lamp with an asbestos wick and a fuel composed of sulphur and spiritus vini, which Abbot Trithemius supposedly gave to Emperor Maximilian I as a present.  But the fuel used in the everburning lights of Padua came to hold a special place in alchemical lore. By 1529 Hermolaus Barbarus had already identified it as a “divine water of the chemists” known to Democritus and Hermes Trismegistus, who spoke of it as ‘Scythian water’ and a “spirit from the nature of the ether”; significantly, he adds that it is the substance with which aurum potabile and the Philosophers’ Stone are manufactured.  Conrad Gesner also cited the story of the Paduan discovery as proof of the antiquity of the art of distillation and sublimation, and supposed that Cardanus had once spoken of the same divine water.  But he confesses he does not know the secret of its manufacture. Khunrath would no doubt have ascribed this ignorance to the fact that Gesner was a ‘four-elementer’ (quatuor elementistarum), i.e. one who works only with the four mundane elements and who is unable to research the matter ‘theosophically’.
Khunrath, on the other hand, claims knowledge of this divine water, and would reveal its identity if only he were authorised to “break the heavenly seal and divulge the mysteries of God”; as it stands, he feels it is only right that the sons of the doctrine should be encouraged to ‘theosophically’ consider the various clues he supplies.  One of these clues stands in the 1595 edition of his Amphitheatrum in the form of a table correlating the substances named in the Genesis creation account (earth and water, heaven and the breath of God) with the principles and substances of the Hermeticists, ‘ancient philosophers’, physico-chemists and four-elementers.  What to Moses was ‘heaven’ (shâmayim), was to Hermes the spiritus mundi, ether and a corporeal spirit permeating all things; to the antique Greek philosophers a medium between matter and form; and to physico-chemists such as Khunrath, Mercury or a ‘spiritual ether’ which operates “in accordance with the scintilla of nature with which it is joined.” 
In order to understand these correspondences, it is necessary to delineate a central feature of Khunrath’s cosmology – the concept of an all-pervading ‘heaven’ (Hebrew shâmayim), which is threefold in its structure, and which can be manifested to the human senses through the work of a talented alchemist.  Elohim resides with his angels in the uppermost, third or empyrean heaven,  an eternal ‘fiery water’ composed from the upper waters, variously described as an ‘impenetrable light’, the quintessence, an ‘aethereal fertility’ and a divine water known to the alchemists. Beneath the empyrean heaven lies the firmament (râqîya shâmayim) or second heaven, composed of the same ‘fiery water’ which was congealed by God into a ‘solid arch’ more durable than diamond, in order that it supports the upper waters and is not annihilated by the heat of its own light and fire (i.e. that of the sun, moon and stars God has placed there). 
Beneath the firmament lies a ‘great empty space’ filled with ‘watery humours’ and the vapours which daily rise from the lower regions – the site of a condensation and rarefaction akin to that which takes place in the alchemical vessel. The first or inferior heaven is also composed of the same ‘fiery water’ as those above it, but it interpenetrates and is mixed with the material sublunary world which God has created from the prima materia (‘Chaos’, ‘Abyss’, composed of the Philosophical Gold/Sulphur and Philosophical Silver/Mercury we have mentioned).  Here too there are stars, Khunrath tells us, which sympathetically follow the motion of the upper stars – a reference to the scintilla which were scattered throughout “the great mass of the prima materia” by the breath of God (rûwach Elôhîm).  All earthly things have been lent their forms or signatura by God through rûwach Elôhîm, a ‘spirit’ or ‘vapour’ which is “an emanation of primeval archetypes or patterns” conceived in the mind of God.  This rûwach Elôhîm is also described as ‘Nature itself’ and the anima mundi; as pure form it can only be united with its opposite (matter) through the medium of heaven, shâmayim, which union is described in sexual terms as the pouring forth of semen and warmth by God into virginal matter. 
Notwithstanding his employment of the nomenclature of the Genesis creation account, Khunrath’s basic cosmological conceptions are thus more or less identical with those of the greatest magus of the Renaissance, Marsilio Ficino (1433-1499). Shâmayim is the Ficinian spiritus mundi, which is described in Ficino’s De Vita as precisely ‘heaven’ and the quintessence, and which acts as the all-pervasive medium allowing the generative power of the anima mundi (Khunrath’s rûwach Elôhîm) to act upon the lower, grosser world.  In any case, it is clear from the foregoing that the divine water of Padua – and here we are also speaking of the Mercury of the Wise mentioned in Lux Lucens in Tenebris – was thought of by Khunrath as a medium for nothing less than the seminal power of God, the “blessed green which makes all things fruitful.”  This is to be found in the lower world in the form of fiery sparks of the world soul, the ‘scintilla of nature’ which need the heavenly water (spirit) as their vehicle in order to be united with and give form to matter (body). 
Hence the procedures described in Lux Lucens in Tenebris constitute a microcosm of the genesis of the world; just as Khunrath describes the universe as the “macrocosmic laboratory of God,” so the alchemist forms an image of the Creator standing above the vessel of his own creation.  The reduction of the gold to its prima materia constitutes the breaking of those natural bonds which unify the metal’s Sulphur, Salt and Mercury, and is likened in Khunrath’s manuscript to the reproduction of that watery, chaotic state of matter preceding the creation of the world in Genesis 1.2.  Likewise, the ethereal Mercury of the Wise which brings life to the chaos is the medium for the animating breath of God, which moves over the face of the waters in the Genesis account. This grants to all things created their form or entelechia, the inner telos which drives their process of becoming. 
between the biblical creation story and the alchemical work were commonplace
amongst alchemists in the early modern period;  they constituted a common
means of legitimising the alchemical work with recourse to Scripture, and
complemented the medieval parallel drawn between the Philosophers’ Stone as the
perfection of the alchemical work and Christ as the crown of creation and
saviour of the microcosm which is man. The Hellenistic Tabula Smaragdina, a
central text in the transmission of alchemical lore to both Arabia and the
West, provided the precedent for likening alchemical process with the Creation:
This is the mightie power of all power, for it shall overcome every subtile thing, and pearce through every solide thing. So was the worlde created. 
Ficinian and heterodox Lutheran influences aside, Khunrath’s alchemy as we have described it here reflects the standard preoccupations of the alchemical canon, not only with regard to notions of virtue and penetrativity, but above all in relation to the unification of spiritual and material principles in an agent of transmutation. As the Tabula Smaragdina puts it, the father of all the perfection of this world is here. His force and power is perfect, if it be turned into earth. 
And know that the Heaven is to be joyned in a mean with the Earth: But the Figure is to be in a middle Nature, between the Heaven and the Earth, which thing is Our Water. 
As psychologist C. G. Jung plausibly asserted, it is the coniunctio oppositorum which forms the central symbolic complex of the alchemical literature.  Closely allied with this theme is the endeavour to draw down to earth a divine, heavenly or spiritual principle – as Maier puts it, “God gives power to the sun, the sun to the gold, this eventually to the human heart” – a fact which prompted Metzger (again, plausibly) to speak of vitalism as the defining characteristic of alchemy vis-à-vis modern chemistry. 
we must reject the ‘presentist’ assertion that alchemists were only “working on
material substances towards material goals.”  If corpuscularian texts with
little or no recourse to vitalistic concepts are to be found in the medieval
period, this fact only reveals alchemy to be a subset of chemistry as it has been
practised since time immemorial – it is simply another chemistry with a
paradigm largely alien to the contemporary scientific worldview.  Nor
should we imagine that any chemistry, modern, early modern or medieval, exists
without a psychological and cultural subtext. Thus Jung once proposed that
alchemy is “a chemical research into which there entered an admixture of
unconscious psychic material by the way of projection.”  In the course of
pillorying the valuable contributions of Jung, Newman and Principe counter this
proposition with the following entirely untenable statement:
...if the images used in alchemical texts are in fact irruptions of the unconscious, then there would be no possibility of “working backwards” from them to decipher such images into actual, valid laboratory practice. 
There are, of course, very obvious parallels which can be drawn between psychological and chemical process (first and foremost being the dissolution and recombination of spagyria), a fact reflected in Goethe’s Die Wahlverwandschaften, for example. That the processes in the alchemical vessel were guided by a recognised chemical logic in no way precludes the possibility that another purely subjective logic came into play through the assignment of Decknamen to those processes by imaginative association (i.e. via the phenomenon of pareidolia). Furthermore, the conception that a symbol possesses more than one connotation is central to alchemy in particular, as well as to the Hermetic worldview in general (as we have already noted). Indeed, it would appear that the rise of modern chemistry was marked by the gradual disintegration of Hermeticism as the dominant cosmological paradigm, and by a concomitant devaluation of the mesocosm of the imagination as a tool for knowledge of things divine in humanity and cosmos. A hard demarcation between the stuff of matter in the outer world and the constituent elements of the observing subject does not exist in alchemical natural philosophy, a fact which leads one to suspect that the main fault in the Jungian theory of alchemy lies in his postulation of an unconscious projection. Indeed, if contemporary scientific discourse is almost as heavily psychologically laden with the neuroses and fantasies of largely reclusive male scientists as alchemical symbolism, then the distinction between the two languages stems more from the fact that today’s laboratory workers are less conscious of the mythic, imaginary dimensions of their enterprise.
Whilst the Hermetic worldview may well have been sequestered from the scientific mainstream in the course of the Enlightenment, it continued to live on in esoteric circles – not merely in the form of a ‘spiritual alchemy’ focused exclusively upon a mystical inner transformation, but also in the form of laboratory work. Unless we wish to erase from history the development of alchemical thought subsequent to the seventeenth century, we must reject the suggestion of Newman and Principe that early modern alchemy be referred to by the terms chemia or chymia, and that the term ‘alchemy’ should be applied to the medieval period alone.  Whilst these authors make brief mention of the fact that the thought of Heinrich Khunrath persisted amongst ‘secret societies’, they summarily dismiss the developmental continuity of the Western esoteric tradition on the grounds that, in the hands of such societies, “alchemical works deliberately written to be obscure and secretive in their own age became meaningless in the next.”  I, for one, find nothing ‘meaningless’ in either the practical alchemy of the Gold- und Rosenkreutz or the purely spiritual alchemies of fringe Masonry (such as we find in the works of Hitchcock and the younger Waite). With regard to the former, there still exist communities of practical alchemists in the world today; with regard to the latter, ‘spiritual alchemy’ is merely a natural extension of Hermetic ideology emerging from the individualist sentiments and ‘reflective activity’  inspired by the Protestant Reformation.  Whilst the alchemical interests of Newton and Boyle show that modern chemistry did not emerge from alchemy in a day, a year, or even the lifetime of one great innovator, the historiography proposed by Newman and Principe still fails to address that manifest post-Reformation fission of the physica and the mystica of which Jung spoke.  If we choose to ignore this schism by removing esotericism from our picture of modernity, or by belittling the mystica as the “product of a disordered mind,” then we are only exposing that divided, fragmented consciousness characteristic of the modern and postmodern psyche. 
On the other hand, a conception propagated today by certain followers of practising twentieth century alchemists such as Fulcanelli (and implicit in much of the alchemical corpus) is that there exists a unique Magistery or Work possessed by all adepts in the long history of alchemy; from this perspective, the symbolism of alchemy points towards a single, correct method for creating the Philosophers’ Stone (or alternatively two correct methods, i.e. a ‘wet’ and a ‘dry’). It is evident, however, that not all alchemists worked with tetrachloroauric acid (for example), since the employment of aqua regia emerges at a relatively late stage in the history of alchemy. Rather than striking the names of Basil Valentine and Heinrich Khunrath from that glorious list of adepts, it behoves us to accept that we are dealing with a range of interpretations of a more-or-less constant symbolism, as opposed to a single carefully-guarded chemical process which is signified throughout the alchemical canon.
Our reflections here on the shifting of chemical paradigms provide no grounds for adopting a Kuhnian post-positivist relativism, or an agnosticism concerning the beliefs of the alchemists; for despite the varied methods employed by the ‘adepts’ to transmute metals, deception seems to be a unifying factor in their claims of success. In his polemical Adeptus Ineptus the pastor Georg Wilhelm Wegner (1692-1765) once spoke of both self-deception and fraud in this regard, and characterised the alchemists as “thieves to themselves and their needy neighbours.”  We may well point in protest to the many contributions to the advance of science and technology made by the alchemists, or perhaps even to the legitimacy of gilding and alloying techniques, and to variant definitions of the word ‘gold’; but the stubborn fact remains that the treasures held at the heart of the alchemical labyrinth – unlimited wealth, revelation and eternal life – remained undiscovered by those errant explorers who stumbled their way through the darkened corridors of experiment. In the case of Khunrath’s career self-deceit is very much a factor, as he clearly believed silver could be transmuted into elemental gold in the manner described in his Lux Lucens in Tenebris – despite being aware of the various methods for ascertaining the purity of golden objects.
Whilst Wegner explained such self-deception with recourse to the alchemists’ greed for worldly wealth, this clearly does not suffice to clarify the motivations of a pious iatrochemist such as Khunrath. One might also turn to the paradigm of memetics to understand the persistence of alchemical ideology in the face of lost fortunes and lives cut short by heavy metal poisoning; but it seems to me that the theories of Jung are most useful here. For we may well be dealing with a form of Ergriffenheit, a state of being ‘seized’ or possessed by archetypal thought processes relating to certain primordial desires – a phenomenon which is most clearly illustrated in the figure of Goethe’s Faust. From this perspective alchemy appears primarily as a magical or even religious artefact, and the unswerving faith in the reality of its promises (a faith still to be observed today) derives above all from the seductive, numinous power of its Promethean mythology. This is a mythology which lives on – albeit largely unrecognised – in the endeavours of the inheritors of the alchemical mantle, in the form of a penetration into the farther reaches of Nature (now divested of its sacred character by deicide) to obtain a feminised arcanum.
 Quirinus Kuhlmann, Der Neubegeisterte Böhme, ed. Jonathan Clark. Stuttgart: Anton Hiersemann, 1995, pp. 111-112; c.f. Heinrich Khunrath, Vom Hylealischen, das ist, Pri-materialischen Catholischen oder Allgemeinen Natürlichen Chaos, der Naturgemässen Alchymiae und Alchymisten (hereafter Vom Chaos), Magdeburg: Andreas Gene, 1597, p. )()(8.
 Johann Moller, Cimbria Literata, Vol. 2, Hanau: Orphanotrophius, 1644, p. 440.
 See Gottfried Arnold, Unpartheyische Kirchen– und Ketzer– Historie, Frankfurt am Main: Thomas Fritsch, 1715, pp. 11-13.
 Joachim Telle, “Khunrath’s Amphitheatrum – ein frühes Zeugnis der physikotheologischen Literatur,” in Elmar Mittler et. al. (eds.), Bibliotheca Palatina: Katalog zu Ausstellung vom 8. Juli bis 2. November 1986, Heiliggeistkirche Heidelberg, Vol. 1, Heidelberg: Braus, 1986, p. 346.
 Moller, Cimbria Literata, Vol. 2, p. 441.
 Johann Valentin Andreae, Mythologiae Christianae, sive Virtutum et vitiorum vitae humanae imaginum, Strasbourg: Lazarus Zetzner, 1619, p. 137.
 Johann Dietrich, Antiquitates Biblicae, Gießen: Jakob Gottfried Seyler, 1671, p. 132.
 Jacques Gaffarel, Curiositez inouyes, sur la sculpture talismanique des Persans, Horoscope des Patriarches, et Lecture des Estoilles. Paris: Hervé du Mesnil, 1629, pp. 595-596.
 See, for example, Johann Ludwig Hannemann, Ovum Hermetico-Paracelsico-Trismegistum. Frankfurt am Main: Friedrich Knoch, 1644, p. 130.
 Böhme, regarded by Joost Ritman as “the most important publisher of his time,” brought out the following works of Khunrath: Alchymisch-philosphisches Bekenntnis vom universellen Chaos der naturgemässen Alchymie (1786); Magnesia Catholica Philosophorum (1784); Wahrhafter Bericht vom philosophischen Athanor und dessen Gebrauch und Nutzen (1783) and De Igne Magorum Philosophorumque secreto externo et visibili (1783).
 Telle, “Khunrath’s Amphitheatrum,” p. 346.
 Khunrath, Vom Chaos, pp. 27, 55-56.
 Compare the statue of Mercury at a crossroads pointing to the earthly paradise (i.e. conjunction of material and spiritual principles) in Michael Maier’s Symbola Aureae Mensae. Frankfurt am Main: Lucas Jennis, 1617, p. 592.
 Ludwig Combach, Tractatus aliquot chemici singulares summum philosophorum arcanum continentes. Hofgeismar: Sebald Köhler, 1647, p. 13: “Erat ... in manibus opusculum Dr. Henrici Khunrath Lipsens, Lux Lucens in tenebris, Germanice scriptum, Isagogicum plaene et tyronibus procul dubio utilissimum, quod dignum judicabam ut primum locum inter hosce tractatulos occuparet, eaque de causa in Latinam linguam transfundere volebam, quo Philochemia haberent quasi Mercurium aliquem in bivio, legitimam viam monstrantem, sed nescio quo casu exciderit libellus ille, ut hisce nundinis publicari non potuerit.“
 Heinrich Khunrath, Lux Lucens in Tenebris, Hamburg SUB MS Cod. Alchim. 674 (17 pp.); it is not to be confused with the Lux Lucens in Tenebris appearing in Salomon Trismosin’s Aureum Vellus, Hamburg: Liebeszeit, 1708 (first edition 1598), pp. 636-643, nor with Khunrath’s own Lux in Tenebris, Copenhagen KB, GKS 1765 4°, 141r-151v, and Erlangen UB, Ms. B 266.
 Daniel 2.20-21
 Psalms 36.9: “For with thee is the fountain of life; in thy light do we see light.”
 Daniel 2.23; Lux Lucens in Tenebris, p. 1: “Gebenedeÿet sei der nahme des Herren von Ewigkeit zu Ewigkeit den er hat der weißheit und kraftt grundgeleget, Er verendert zeit und alter, bestetiget setzet und versetzet die Reiche der welt, er giebet verstand den Klugen und weißheit den Weisen, er offenbahret das tieffe und verborgene, und kennet das so im finsternuß und dunkeln wohnet und mitt Ihm ist das liecht. Herr bei dir ist der brun des lebens und in deinem liechte werden wir erleuchtet und sehen wie du alles durch deine gebenedeÿete weisheit wunderbahrlich geordnet hast, dir Gott der Väter dancke ich, dich lobe ich daß du mir verstand und kraftt gegeben, und mir gezeiget hast dieses, darumb ich gebeten.”
 Khunrath, Vom Chaos, pp. 42-44.
 Walter Pagel, Paracelsus: An Introduction to Philosophical Medicine in the Era of the Renaissance, Basel: Karger, 1982, pp. 356-357.
 Khunrath, Vom Chaos, p. 42: “Diesem Licht (leucthende in allen Creaturen/ Geistlichen und Leiblichen/ in Engeln und andern Geistern; im Himmel/ Erde und Wasser; im Tage-Lichte/ in Wassern über der Veste des Himmels/ in der Veste des Himmels/ in der Lufft; auff Erden/ im Bauch der Erden/ in Felsen/ Steinen/ Bergen und Thalen/ in Metallen und Mineralien; in Graß/ Kräutern und Baümen; in allem Gevögel und Thieren auff Erden; in Wassern; in der Tieffe des Meeres/ und in allem so darinnen lebet/ sich reget/ schwebet und webet; im Vieh/ Gewürmen und Thieren auff Erden; im Menschen; Dann Herr dein Unvergänglicher Geist Ist In Allen!)...” C.f. Book of Wisdom 12.1.
 Apart from Psalms 36.9, we find the fountain of life mentioned in Revelations 16.17, Jeremiah 2.13 and Joel 3.18; in the alchemical literature the most striking emblematic depiction is to be found in the Ripley Scrowle (Bodleian Library, MS Ashmole Rolls 52 & 53), which shows a benevolent alchemist with a cloak and forked beard looking down upon the red fountain in the vessel just as God looked down upon the creation. In his ‘Zwölff Schlüsseln’ (Alter und ubriger philosophischer Schrifften und Bücher, ed. Salomon Trismosin, Leipzig: Grosse, 1599, p.33) Basil Valentine warns that the purity of this fountain must be maintained, lest its progeny be deformed: “Mein Freund sol aber ein fleissiges Auffsehen haben/ daß der Brunn des Lebens lauter und klar befunden werde/ Denn keine frembde Wasser müssen sich in unserm Brunnen vermischen/ auff daß keine Mißgeburt entstehe/ und auß einem gesunden heilsamen Fisch eine Schlange herfür krieche...”
 Khunrath, Lux Lucens in Tenebris, p. 1.
 Johann Valentin Andreae, Fama Fraternitatis, ed. Pleun van der Kooij, Haarlem: Rozekruis Pers, 1998, p. 72: “Ob wol nun auch hiermit der unbesonnenen Welt wenig gedienet, und des Lästerns, Lachens und Gespöts immer mehr ist, auch bey den Gelehrten der Stoltz und Ehrgeitz so hoch, daß sie nicht mögen zusammen tretten und auß allem, so Gott in unserm Seculo reichlich mitgetheilet, ein librum Naturae oder Regulam aller Künsten samlen möchten, sondern je ein theil dem andern zuwider thut, bleibt man doch bey der alten Leyren und muß Bapst, Aristoteles und Galenus, ja was nur einem Codice gleich siehet, wider das helle offenbahre Liecht gelten...”
 Khunrath, Vom Chaos, pp. 44-45.
 Khunrath, Lux Lucens in Tenebris, pp. 1-2; on this theme, see Khunrath’s De Igne Magorum Philosophorumque secreto externo et visibili, Straßburg: Zetzner, 1608, p. 26: “Die aber nicht schlechterdings heidnisch, sondern in Tugenden und guten Werken, und in der Liebe gegen den Nächsten, vielleicht christlicher waren, als etwa heutiges Tages etliche auch geistlich genannte, und vermeinte, und Maulchristen.”
 Khunrath, Lux Lucens in Tenebris, p. 2.
 Augustine, De civitate Dei, 18.23; Paulys Realencyclopädie der classischen Altertumswissenschaft, ed. Georg Wissowa, Vol. 10.1, Stuttgart: Alfred Druckenmüller Verlag, 1934, pp. 2248-2252.
 Pierre Abélard, “Introductio ad Theologiam,” in Opera Omnia (Patrologia Latina, Vol. 178), Paris: Migne, 1855, p. 1008.
 On this matter, see Barbara Obrist, Les Débuts de l’Imagerie Alchimique (XIVe – XVe siècles), Paris: Le Sycomore, 1982.
 Khunrath, Lux Lucens in Tenebris, pp. 2-3.
 Khunrath, Vom Chaos, pp. 19-20.
 Khunrath, Lux Lucens in Tenebris, p. 3: “...man wolle dieses buchlein das lästermauler nicht zukommen lassen, sondern der Philosophorum meinung nach geheim halten, und fur eine sonderliche gabe Gottes bewahren...”
 Apart from pursuing a private practice in Dresden and Hamburg, according to the chronicler and librarian Václav Beza (1568-1618) Khunrath was appointed as a physician to the Bohemian nobleman Wilhelm von Rosenberg (Vilém z Roûmberka) on the 15th of December, 1591. Kind information of Anna Kubíková, Státní oblastní archiv, Krumlov.
 Johann Christoph Adelung, Geschichte der menschlichen Narrheit, Leipzig: in der Weygandschen Buchhandlung, 1787, p. 91.
 Consilium de Vulcani Magica Fabrefactione Armorum Achillis, Stockholm, KB MS Rål 4, 1597 (43 ff.); on the subject of this manuscript, see my article “Of Electrum and the Armour of Achilles: Myth and Magic in a Manuscript of Heinrich Khunrath (1560-1605),” forthcoming in the Journal of the Warburg and Courtauld Institutes.
 Khunrath, Consilium, titlepage: “Und ist dis Löbliche furtreffliche Kleinod und wergk bisanhero in höchster geheimb gehaltenn wordenn unnd noch billig also zuhaltenn.”
 Johannes Staricius, Heldenschatz/ das ist; Naturkündliches Bedencken uber und bey Vulcanischer auch Natürlicher Magischer Fabrefaction und zubereitung der Waffen deß Helden Achillis in Griechenlandt. Darauß neben vielen Secretis zu vernehmen/ was zu Martialischer Außrüstung eines Kriegshelden vornemlich gehörig, Frankfurt am Main: n.p., pp. A5 verso – A6 verso, 120-123.
 Khunrath, Lux Lucens in Tenebris, p. 5; as in the works of other alchemical authors such as pseudo-Arnaldus de Villanova and Johannes von Rupescissa, Khunrath’s work begins with a preliminary theoretica and proceeds with a practica.
 Lux Lucens in Tenebris, p. 5: “Was uber die wahrhafftige mãa lapidis sey, und wie sie bekommen werden, stehen allen Philosophen bücher vol, ob es schon von vielen nicht verstanden wird. Wollest derhalben die gebehrung des Menschen bedenken und mit den Philosophi sagen: Ein iedes zeuget und gebuhret vor Ihnen seines gleichen und was du seest, daselbe wirstu auch einerndten”; c.f. Tractatus Aureus, Musaeum Hermeticum, 1624 (translated by Arthur Edward Watte from the expanded 1678 edition as the Hermetic Museum Restored and Enlarged, London: James Elliot, 1893, pp. 13-14) it is said “‘But nothing,’ says our Richard, in his first chapter, ‘can be got out of a thing which is not in it. Therefore every species, every genus, every natural order, is naturally developed within its own limits, bearing fruit after its own kind, and not within some other essentially different order: everything in which seed is sown must correspond to its own seed... a thing can be developed and improved only by that which belongs to its own nature... If any one wished to change a man into a horse, an apple into a lettuce, a diamond or any other jewel into gold, he would make an enormous mistake.’”
 Khunrath, Lux Lucens in Tenebris, p. 5: “Den von einem Menschen wird nichts anders alß ein Mensch gebohren”; c.f. Turba Philosophorum, dictum 29.
 Abu’l-Q?sim Muhammad ibn Ahmad al-Irq, Book of the Knowledge Acquired Concerning the Cultivation of Gold. Tr. E. J. Holmyard. Paul Geuthner: Paris, 1923, pp. 11-12.
 On the subject of this debate, see de Jong, H. M. E. Michael Maier’s Atalanta Fugiens: Sources of an Alchemical Book of Emblems, Leiden: E.J. Brill, 1969, pp. 17, 155-157.
 c.f. Khunrath, Vom Chaos, pp. 191-192: “In oder vermittelst einem bequemen Acker/ bringt gleiches seines gleichen... so mustu auch nothwendig Silber oder Gold/ ein jedes auff seines gleichen Saamen weise darzu nehmen; dieweil in diesen beyden Metallen die tingirenden Füncklein und Strahlen des Liechts der Natur Silberisch oder Göldisch stecken und zu finden seynd.”
 Lux Lucens in Tenebris, p. 5: “...die Sonne ist ein volkommen Corpus, ein herr aller Steine, ein König und haubt aller anderen, welche mag weder die erde zu nichts bringen, noch durch irgend etwas verbrand werden, wird auch nicht vom fewer geringert sondern gebeßert, den es in ihnen mit einer sonderen feuchte befeuchtiget wird.”
 c.f. this theory as it is found in Avicenna de congelatione et conglutinatione lapidum, ed. and trans. E. J. Holmyard and D. C. Mandeville, Paris: Geuthner 1927.
 Khunrath, Lux Lucens in Tenebris, pp. 5-6: “Seine Complex und natur ist temperirt und weder zu hitzig noch zu kalt, weder zu feucht noch zu trucken, den es ist erschaffen auß der subtilesten und klaresten substantz des quecksilbers und weniges reines Schweffels, welcher alß eine fixe und klare rohte der substantz des quecksilbers die farbe giebet. Nun solcher der goldnatur nachzureden, weil lap. Phil. durch sein temperament und volkommenheit alle unsauberkeit beydes an Menschlichen Cörpers und metallen hinnimbt und dieselben reiniget und enderet, und kein qualificirter temperirter oder volkommener Corpus gefunden wird alß Q, muß auch nohthalben folgen, das der Lap. Phil. auß der mãa [materia] und substantz oder wesen der Q gemachet werden muß. Den eine jedere tinctur sol von seines gleichen außgehen und herkommen. Jedoch kan solches ohne gebuhrliche mittel nicht sein, sondern ihr Corpus mus gebrochen werden, damit man ihre Tinctur herfurbringen.”
 Khunrath, Lux Lucens in Tenebris, pp. 2-3: “Derohalben alle ihre schreiben, nicht ohne sondern acht solche kunst geheim zu halten beschehen seynd, auch ihre parabolische bücher auch der wahren discipulis et filiis artis verborgen und dunckel genug hinterlassen. Ist derwegen keine bewunderung wahrt, obschon wenig zur wahren erkantnus dieser Medicin kommen, den diese kunst ist eigentlich und gewis eine herliche gabe Gottes, die ohne sonderliche furschung Gottes nicht iederman wiederfahret oder offenbahret wird.”
 Khunrath, Vom Chaos, p. 141.
 Michael Maier, De Medicina Regia et vere heroica, Coelidonia, Copenhagen, Royal Library, MS 12,-159, 4º. Prague: n.p., 1609, p. 93.
 Michael Maier, Atalanta Fugiens, hoc est, Emblemata nova de secretis naturae chymica. Oppenheim: Johann Theodor de Bry, 1617, discourse 22: “Saturnus omnium gentilium aut potius aureolorum pater est, et prima porta arcanorum: Cum hoc, inquit Rhasis in epist. aperiuntur portae scientiarum.”
 Alexandre T. de Limojon de Saint-Didier, Le triomphe hermetique, ou La pierre philosophale victorieuse. Traitté plus complet & plus intelligible, qu'il en ait eu jusques ici, touchant le magistère hermetique, Amsterdam: chez Henry Wetstein, 1689: “...pourquoy ne te faches-tu pas plustost contre Dieu, et pourquoy ne lui demandes-tu pas, pour quelles raisons, il n’a pas créé en toy, ce qui se trouve en moy?... tu n’es pas cet Or, dont les écrits des Philosophes font mention; mais cet Or est caché dans mon sein... aussi s’en trouve-t-il à peine un entre cent, qui travaille avec moy. Ils s’appliquent tous à chercher (la verité) de l’art dans toy, et dans ton frere Mercure: c’est pourquoy ils errent tous, et c’est en cela que leurs travaux sont faux. Ils en font eux-mesmes un (bel) exemple: car c’est inutilement qu’ils emploient leur Or, et qu’ils tâchent de le détruire: il ne leur reste de tout cela, que l’extrême pauvreté, à laquelle ils se trouvent enfin reduits. C’est toy Or, qui es la premiere cause (de ce malheur,) tu sçais fort bien que sans moy, il est impossible de faire aucun or, ni aucun argent, qui foient parfaits; et qu’il n’y a que moy seule, qui aye ce (merveilleux) avantage.”
 See Julius Ruska, Das Buch der Alaune und Salze: Ein Grundwerk der Spätlateinischen Alchemie, Berlin: Verlag Chemie, 1935, p. 91-92.
 Vom Chaos, 142-143, 145.
 Khunrath, Vom Chaos, pp. 141-142: “Es kan Aurum vulgi sive Metallicum nicht warhafftig und Naturgemäß-künstlich Potabile gemacht werden/ ohne Aurum Philosophorum... Aurum potabile Philosophorum Catholicon, wird nicht von gemeinem Metallischen Golde præpariret, sondern nur alleine ex Magnesia... Animam Magnesiæ ist Q Philosophorum. Aus unserer Catholischen Saturnischen Erde oder Minera Magnesiæ, wird Unser Q und R Sulphur und S/ geschmeltzt und gezogen... Diese beide componiret in wässeriger Gestalt/ seind Azoth sivè S Phil. Universalis.” Two different types of aurum potabile seem to be indicated here, which appear to correspond to the lesser and greater Philosophers’ Stones we will soon discuss.
 Khunrath, Lux Lucens in Tenebris, p. 6: “Nimm fein golt durch die quartier oder Antimonium zum allerhöchsten gereiniget, solches solvire in einem starken Aqua Regis zu Crystallen...”
 Georg Agricola, 381 f. gives a very clear description of the manufacture and use of Aqua Fortis or Scheidewasser in his De Re Metallica Libri XII, Berlin: VDI-Verlag, 1928 (German translation of the 1556 Basel edition), pp. 381 f.; c.f. Conrad Gesner, The treasure of Evonymus Conteyninge the wonderfull hid secretes of nature, London: Daie, 1559, pp. 320 f. Potash alum is a synonym for potassium aluminum sulfate; the vitriol (metallic sulfate) utilised was commonly ferrous sulfate.
 See Christophe Glaser, Traité de la chymie, enseignant par une briève et facile méthode toutes ses plus nécessaires préparations, Paris: Jean d’Hovry, 1668, pp. 84-87.
 See, for example, Peter Joseph Macquer, Chymisches Wörterbuch, Vol. 2, Leipzig: M. G. Weidmanns Erben und Reich, 1781 (French edition first published in 1766), p. 699; Johann Joachim Becher, Chymischer Glücks-Hafen, Frankfurt am Main: Johann Georg Schiele, 1672, p. 535, gives 10 Loten (160 grams) sal ammoniac to 1 pound (500 grams) of aqua fortis.
 E.g. Lazarus Ercker, Aula Subterranea, d.i./ Beschreibung/ Allerfürnemisten Mineralischen Ertz- unnd Bergkwercks arten, Frankfurt am Main: Feyerabend, 1580, p. 68.
 On this matter see Edmund O. von Lippmann, Entstehung und Ausbreitung der Alchemie, Vol. 1, Berlin: Julius Springer, 1919, pp. 487-488.
 Used to warm the vessel without applying the direct heat of the fire.
 See Macquer, Chymisches Wörterbuch, Vol. 2, p. 699, who also mentions the heating of gold leaf together with alum, saltpetre and sodium chloride, thus making a ‘kind of Königswasser which is named the quiet solvent, menstruum sine strepitu, because it dissolves the gold without any noise’ (p. 708). For related techniques for dissolving metals, see Gesner, Treasure of Evonymus, p. 318 and Agricola, De Re Metallica, pp. 384-385.
 Egon Wiber and A. F. Holleman, Lehrbuch der anorganischen Chemie, Berlin: Walter de Gruyter, 1971, p. 565; E. Zschimmer, “Der Goldrubin,” Sprechsaal für Keramik, Glas- und verwandte Industrien, Vol. 63, No. 34, October 1930, p. 642.
 Khunrath, Lux Lucens in Tenebris, p. 6: “...solches solvire in einem starken Aqua Regis zu Crystallen, das geschieht, wen die phlegma oder das Aqua Regis biß auf die olitet abgezogen und solche solutio in eine Kuhle stätt gesetzet wird.” The production of red crystals of gold chloride was first described with precision by Andreas Cassius in his De extremo illo et perfectissimo naturae opificio ac principe terranorum sidere auro (hereafter De Auro), Hamburg: Georg Wolff, 1685, p. 100 f.; Johann Juncker, Conspectus Chemiae Theoretico-Practicae, Vol. 2, Halle: In Verlegung des Waisenhauses, 1750 (original Latin edition 1738), p. 282, describes the production of red gold crystals through the reduction of tetrachloroauric acid to a ‘phlegm’; Macquer, Chymisches Wörterbuch, Vol. 2, p. 702, describes the growth of yellow crystals similar to topaz when tetrachloroauric acid is left to cool.
 Juncker, Conspectus Chemiae, Vol. 2, p. 282.
 Khunrath, Lux Lucens in Tenebris, p. 6: “Dieselbe Crystallen mache durch gebuhrliche putrefaction und zugethane mittel zu einem Mercurio wie dir bewust, so hastu das Corpus Solis das erste mahl gebrochen, und in die erste nahe mãam gebracht: den es ist gewis das ein iegliches ding von dem und auß dem herkommt, in welches es gehet in seiner auflösung. Nun kan das golt und alle Metall zu einem Mercurio gemachet werden, derselben sie in der ersten auch Mercurius gewesen seynd. Die verkehrung aber der Cinerum der Metall in einem Spiritum ist, das so fix ist, volatile machen das ist zu einem Mercurio Philosophorum. Derselben so verkehre die Aschen des Königs der Metallen in einem geist, das es werden zu einem lebendigen Mercurio so hastu den wahren anfang dieser kunst: den das Mercurius ist nun wurtzel Mutter und haubtquel aller volkommenen und unvolkommenen Metallen: und wiße das allein in ihm und in keinem andern frembden die größeste heimligkeiten beyder die Menschliche Cörper damit zu curieren und auch die Metall zu verkehren und zu reinigen hafften und stehen...”
 On this matter see Hans-Werner Schütt, Auf der Suche nach dem Stein der Weisen, Munich: C. H. Beck, 2000, pp. 301-302.
 Khunrath, Lux Lucens in Tenebris, p. 8: “Weil ich nun wie erzehlet, mich der kunste befleiße, muß ich melden und anzeigen, wie die Philosophi in bereitung solchen Medicin geprocediret haben, und was sie fur einer weg hirinnen gebrauchet, und ist die erste und furnembste arbeit dieser kunst die sublimation. Das ist die Zerstörung, welche durch die putrefaction geschiehet, was sie aber sublimiren heißen, folget, Nemlich unser sublimiren heißet nicht uber sich steigen, sondern von einem Corrumpirtes und unausehnlichen dinge, das ist von einem Cörper oder aschen der sich itzt nicht bewegen kan, sondern gleich alß fur nichtes und todt lieget, ein herlicher wesen und ding machen, welches bequemer zur tinctur ist, den sein corpus, so es unzerstöret in seiner grobheit verbliebe, und solches heißet den ein Mercur. Philosophor. ein geistliches der erden, die eingehen und zur Tinctur werden kan.”
 Khunrath, Vom Chaos, p. 193: “Jetzt wird nun gefragt/ worein man Silber oder Gold Naturgemäß-künstlich säen solle und müsse/ auff daß sie wieder und Neugeboren/ fruchtbarlich vermehret/ und (auff ihre Weise) hochnützlich verbessert und vervielfältiget werden.”
 Khunrath, Vom Chaos, pp. 193-194.
 Khunrath, Vom Chaos, p. 194: “...die Metalla aber können in ihre erste Materiam nicht widerum bracht werden/ als durch die Erste Materiam, das ist/ durch S/ nicht vulgi, sondern den Erstwelt-anfangs Allgemeinen/ welcher ist S der Weisen.” Compare Martin Ruland, Lexikon Alchemiæ sive Dictionarium Alchimisticum, Frankfurt am Main: Zacharias Paltenius, pp. 96-97: “Azoth est argentum vivum, ex quouis corpore metallico tractum: & proprie Mercurius corporeus, Mercurius corporis metallici... Theophrastus nennet seiner fürnembste Artzney eine also: Vermeinen etliche/ es sey Lapis philosophicus gewesen. Der Azoth wird auß den Cörpern gezogen durch Mercurium/ und wird genennt Spiritus animatus, ein geseelter Geist/ aqua nostra, Essig &c... Geber: Azoth ist der Mercurius/ welcher von den Cörpern durch den Mercurium Philosophorum außgezogen wirdt. Ist also und wirde Azoth ein Elixir, id est, ein auffgelöster Cörper in dem Mercurialischem Wasser. Heist auff Arabisch Azoth ein auffgelöst Silber, &c.”
 Khunrath, Vom Chaos, p. 194: “Es sey dann/ daß das Korn corporis Q vel R werde geworffen in sein allererstes Wesen/ sonst arbeitestu umsonst.”
 Khunrath, Lux Lucens in Tenebris, p. 9: “So nimm denselben Mercurium und truckene ihn auf einem warmen sande in einem glasernen schalen, damit keine feuchtigkeit dabey bleibe, darnach drucke ihn durch ein semisch leder einmahl oder drey wieder in die glaßschalen auf das allerreineste, damit nichts frembdes dazu kommen und sublimiren ihn durch ein Philosophische geheimnus ein und zwantzig mahl, so hastu den rechten lebendigen Mercur. Philsophor. mit welchem all dein werck sol angefangen und geendet werden.”
 Khunrath, De igne Magorum, pp. 1-2.
 On this matter, see Khunrath, De Igne Magorum, p. 32.
 Khunrath, Lux Lucens in Tenebris, pp. 15-16.
 Khunrath, Lux Lucens in Tenebris, pp. 13, 17.
 Hence Khunrath’s recipe belongs to the 2nd class of methods used in alleged transmutations outlined by Karpenko – the surface treatment of common metals (although here silver is utilised) with precious ones. The other methods classified by Karpenko are: 1. Methods of transmutation where the precious metal is contained in the whole volume of the final product (including methods yielding pure metal through either deceitful manipulation or the isolation of precious metals from an alloy, as well as those methods leading to the debasement of precious metals via alloying or cementation); 3. Methods leading to products of golden or silver colour containing no precious metals; 4. Apparent transmutation between common metals; and 5. Fantastic processes, or purely mythic procedures often stemming from ‘corrupted’ interpretations of older texts. See Vladimír Karpenko, “The Chemistry and Metallurgy of Transmutation,” Ambix, Vol. 39, Part 2, July 1992, p. 49.
 Khunrath, Vom Chaos, pp. 78-79.
 Khunrath, Vom Chaos, p. 80.
 Khunrath, Vom Chaos, pp. 83-84.
 See n. 71 above.
 Johann Joachim Becher, Supplementum Secundum in Physicam Subterraneam, Frankfurt am Main: Johann David Zunner, 1675, p.29-30: “Idem contingit in auro, quod si in aqua Regis solvas, addasque Mercurium abstrahendo liquorem ad salis consistentiam, eamque in spiritu aceti resolvendo, filtrando, purgando, et denuo inspissando ad consistentiam, quae cerae instar fluet, ac quodvis argentum etiam in talerorum crassitie in aurum transmutabit, modo candescat citra fusionem, idque cum augmento auri, quae experimenta ideo tantum adduco, ut aperte clareat, aurum vel argentum non alterare nec transmutare metalla, quamdiu in statu soliditatis sunt, verum cum primum subtiliantur, ut penetrare possint, illa statim juxta gradum su? penetrantiae in metalla agere, eaque alterare et transmutare...”
 Becher recommended smelting silver thalers with sea-sand using certain salts as a flux. The Brabant thalers he used in his demonstrations probably contained small amounts of gold; see Karpenko, Chemistry and Metallurgy of Transmutation, p. 50. Gold can in fact be extracted conveniently from sand with the help of quicksilver – but only if the sand contains gold in the first place!
In Becher’s work, the Paracelsian principle of combustibility (Sulphur) became
a terra pinguis (‘fatty earth’), which was renamed phlogiston by Stahl; on the
subject of gold-making with sand, see Pamela H. Smith, The Business of Alchemy,
Princeton: Prinecton University Press, 1994, pp. 253-255.
 Schütt, Auf der Suche nach dem Stein der Weisen, p. 499.
 Becher, Supplementum Secundum, pp. 28-29: “Porro solvatur argentum in aqua forti vel spiritu nitri, abstrahatur solutio lento calore ad consistentiam salis, quod postea solvatur aliquoties spiritu aceti, semper abstrahendo et resolvendo tandem cum spiritu vini sic procedatur, ultimo relinquatur in spiritu vini sal argenti sine abstractione, hic spir. vini sine ulla corrosione, aut violentia, instillatus argento vivo communi, quasi in momento illud figit, ac in argentum transmutat...”
 Becher, Supplementum Secundum, pp. 29-30.
 See n. 51 above.
 Becher, Supplementum Secundum, p. 14; Schütt, Auf der Suche nach dem Stein der Weisen, pp. 132-133.
 Becher, Supplementum Secundum, pp. 25-27.
 Khunrath, Lux Lucens in Tenebris, p. 6: “Est in Mercurio quicquid quaerunt sapientes. Doch solstu keines wegens dadurch den gemeinen Mercurium verstehen, sondern auf das volnkommene Corpus der Metallen sehen und unsere Mercurium daraus ziehen.”
 Khunrath, Vom Chaos, p. 70.
 Khunrath, Vom Chaos, p. 67.
 Khunrath, Lux Lucens in Tenebris, pp. 6-7: “Den so bald du solches Mercurium Solis hast, so glaube festiglich, das du in kurtzen zeit und mit wenig muhe eine solche Medicin den Menschlichen Cörper damit zu vernewren und zu restituiren oder wiederaufzubringen draus machen kanst, das auch keine kranckheit, sie sey wie sie wolle, außerhalb derer die einem Menschen durch die vorsehung Gottes alß eine Straffe, der sunden auferleget verstehen mag. Welches du zum theil an den Mercuriu Precipitato welcher ex Mercurio crudo per aqua fortis gemachet, verstehen magst. Den dieweil der rohe Mercurius nach dem Precipitation, do doch corrosivische dinge zu kommen, ein solches in etzlichen kranckheiten und fällen vermag, was meinestu das solches Mercurius Solis nach der Precipitation, die nicht mit Corrosivisches dingen zugehet, fur krafft und gewalt habe...”
 Gesner, Treasure of Evonymus, p. 328.
 Khunrath, Lux Lucens in Tenebris, p. 7.
 Khunrath, Lux Lucens in Tenebris, p. 7; c.f. Raymund Lull in the Rosarium Philosophorum (http://alchemywebsite.com/rosary3/html): “And for this, that copulation is caused of the subtle parts transmuted and altered into a spiritual form and essence, because it is written that the thick and gross body with the subtle, and the subtle with the thick and gross, cannot conjoin themselves by reason of their contrariety, unless that which is gross be converted into his subtleness by his subtle spirit, and then they are to be mingled together. And this the Philosophers notify by declaring to a follower of the truth, and they say that perfect mixture is the union of mingled and altered bodies joined to themselves by things not to be divided, because these things are here required by manifest reason. Because mixture or union cannot be done or made without alteration which is subtlization of the body and reduction of it into spiritual form.” Compare also the words of Lull in the Tractatus Aureus, Musaeum Hermeticum (Waite, Hermetic Museum, p. 24): "'For the knowledge of the menstruum,' says Raymond (Comp. An., p. i.) 'is a thing without which nothing can be done in the magistery of this Art. Nothing preserves the metals while it dissolves them, but our menstruum,' which, as he further states in his ' Codicil,' is 'the water by which the metals are solved, while all their essential properties are conserved.'"
 Khunrath, Lux Lucens in Tenebris, p. 7.
 Khunrath, Vom Chaos, p. 94.
 Robert Boyle, The Sceptical Chymist, London: Crooke, 1661, p. 180.
 Boyle, The Sceptical Chymist, p. 181.
 Principe, The Aspiring Adept, pp. 43, 62.
 Boyle, The Sceptical Chymist, p. 174.
 Boyle, The Sceptical Chymist, p. 179.
 Cassius, De Auro, pp. 97-98.
 Cassius, De Auro, p. 97: “Nimirum auri drachmae duae solvantur in aqua regis; solvantur itidem aeris viridis unciae duae in aceto destillato: Confundantur solutiones, et dein largissime affusa aqua fontana in vitro per aliquot dies quiescere permittantur: apparebunt filamenta adinstar fili serici per liquoris compagem dispersa, et aurum sensim in atomos minutissimos pulcherrimi splendoris aurei, pro scopo pictorio utiles, praecipitabitur et fundum petet.”
 Khunrath, Vom Chaos, p. 56; also Heinrich Khunrath, Amphitheatrum Sapientiae Aeternae, Hamburg: n.p., 1595, p. 17; for the Duenech allegory, see the Theatrum Chemicum, Vol. 3, Ursel: Zetzner, 1602, pp. 756-757;
 Eilhard Wiedemann, Aufsätze zur arabischen Wissenschaftsgeschichte, Vol. 1, Hildesheim: Georg Olms, 1970, p. 25; Morienus Romanus. A Testament of Alchemy. Stavenhagen, Lee (ed., trans.). Hanover: University Press of New England, 1974, p. 43, n. 58.
 Khunrath, Vom Chaos, p. 56.
 Cassius, De Auro, p. 97.
 Khunrath, Vom Chaos, pp. 66-67, 69.
 Wolfgang Schneider, Lexikon alchemistisch-pharmazeutischer Symbole, Weinheim: Verlag Chemie, 1981, p. 80.
 In his Chrysopoeia, (manuscripts published in Hamburg: Heil, 1718, p. 51), Schwaertzer also mentions a means of producing a ‘ferment’ of gold indispensible for the production of the Philosophers’ Stone by means of tetrachloroauric acid and potassium carbonate (oleum tartari per deliquum, K2CO3) – a rather dangerous procedure, as these are the ingredients of the high explosive known as Blitzgold or fulminating gold. See Willhelm Ganzenmüller, Beiträge zur Geschichte der Technologie und der Alchemie, Weinheim: Verlag Chemie, 1956, p. 111.
 Schwaertzer, Chrysopoeia (cited in Kunckel, Collegium Physico-Chymicum, p. 292).
 Schwaertzer, Chrysopoeia (cited in Kunckel, Collegium Physico-Chymicum, p. 293).
 Johann Kunckel von Löwenstern, Collegium Physico-Chymicum Experimentale, oder Laboratorium Chymicum, Hamburg: Gottfried Richter, 1738 (first published posthumously in 1716), p. 290.
 Juncker, Conspectus Chemiae, Vol. 1, p. 680.
 Thompson once argued that a predecessor of Purple of Cassius is described in an Assyrian clay tablet on the production of artificial coral dating to the 7th century B.C.: see R. C. Thompson, On the Chemistry of the Ancient Assyrians, London: Luzar and Co., 1925, pp. 32, 34. His ascription of a knowledge of the mineral acids to the Assyrians has been largely dismissed, however, although it seems that some antique ruby glass may have been produced with gold rather than the then-customary cuprous oxide: see Ganzenmüller, Beiträge, pp. 85-89, who points to the expression ‘coral gold’ to be found in the Hellenistic (e.g. pseudo-Democritus) and Arabic (e.g. the Turba Philosophorum) alchemical literature. Incidentally, Cornejo (“Beiträge zur Geschichte des kolloiden Goldes,” Zeitschrift für Chemie und Industrie der Kollide, Vol. 12, 1913, pp. 1ff.) looked to Johann Rudolf Glauber, and not Cassius, as the discoverer of ‘purple of Cassius’.
 Kunckel, Collegium Physico-Chymicum, p. 4.
 Kunckel, Collegium Physico-Chymicum, p. 4.
 See the detailed discussion in Jutta Berger, Ideen über die Verwandlung der Stoffe. Chemische Materietheorien und Affinität im 17. und 18. Jahrhundert, Max Planck Institute for the History of Science, Preprint 88, pp. 18-20.
 Ganzenmüller, Beiträge, pp. 114-115.
 Dedo von Kerssenbrock-Krosigk, Rubinglas des ausgehenden 17. und des 18. Jahrhunderts, Mainz: Philipp von Zabern, 2001, pp. 27 ff.
 For an in-depth description of Zsigmondy’s conclusions, see E. Zschimmer, “Das Wesen der Rubinbildung,” Sprechsaal für Keramik, Glas- und verwandte Industrien, Vol. 63, No. 44, October 1930, pp. 833-834.
 The Svedberg, Die Methoden zur Herstellung Kolloider Lösungen anorganischer Stoffe, Dresden: Theodor Steinkopff, 1909, pp. 14, 213; Richard Zsigmondy, “Properties of Colloids: Nobel Lecture, December 11, 1926,” in Nobel Lectures, Chemistry 1922-1941, Amsterdam: Elsevier Publishing Company, 1966, p. 46. A sol is to be distinguished from a solution, in which solvent and solute are entirely homogenous at the molecular level.
 Svedberg, Methoden, p. 213. I am unable to find the relevant passage in the works of Paracelsus which Svedberg adduces as evidence for this assertion; an aurum potabile is described in Paracelsus, “Das sechste, siebente und neunte Buch in der Arznei. Von tartarischen und psychischen Krankheiten und Von Kontrakturen und Lähmungen (1525?),” in Sudhoff (ed.), Sämtliche Werke, Vol. 2, Munich: Oldenbourg, 1930, pp. 475-477, although here there is no mention of tin dichloride. Rather, the ‘redness’ is drawn from the gold with the help of a quinta essentia, a subject which we will address further below.
 Basab Chaudhuri and Syamal Raychaudhuri, “Manufacturing High-quality Gold Sol,” IVD Technology, Vol. 7, No. 2, March 2001, pp. 47-48.
 ibid., p. 47.
 Svedberg, Methoden, p. 209; Elizabeth Fulhame, An Essay on Combustion, with a View to a New Art of Dying and Painting, wherein the Phlogistic and Antiphlogistic Hypotheses are Proved Erroneous, London: published by the author, 1794; cited in Keith J. Laidler and Athel Cornish-Bowden, “Elizabeth Fulhame and the Discovery of Catalysis: 100 years before Buchner,” in New Beer in an Old Bottle: Eduard Buchner and the Growth of Biochemical Knowledge, ed. A. Cornish-Bowden, Valencia: Universitat de València, 1997, p. 124.
 Cited in Svedberg, Methoden, p. 15.
 Svedberg, Methoden, p. 15.
 Juncker, Conspectus Chemiae, Vol. 2, p. 288.
 Macquer, Chymisches Wörterbuch, pp. 733-734: “Uebrigens sind alle diese Goldtincturen nichts anders als ein überaus feingetheiltes und in einer ölichten Feuchtigkeit schwimmend gemachtes natürliches Gold. Sie sind folglich, eigentlich zu reden, keine Tincturen, und können... auch nur in so ferne trinkbares Gold genennt werden, in so ferne man mit diesem Namen keinen andern Begriff als den verbindet, daß das Gold in einer Flüssigkeit schwimmt, und in so feine Theilchen gebracht worden ist, daß es selbst unter der Gestalt einer Feuchtigkeit getrunken werden kann.”
 L. Vanino, “Zu der Geschichte des colloïdalen Goldes,” Journal für praktische Chemie, Vol. 78, 1906, p. 575.
 Khunrath, Lux Lucens in Tenebris, p. 17.
 Krüger (Hofapotheker zu Rostock), “Ueber die Einwirkungen des Eiweisses, des Klebers und der Gallerte auf das salpetrichtsalzsaure Gold,” in Neues Journal für Chemie und Physik, Vol. 3, 1821, pp. 211-212.
 Walter Caseri, “Nanocomposites of Polymers and Metals or Semiconductors: Historical Background and Optical Properties,” Macromolecular Rapid Communications, Vol. 21, No. 11, 2000, p. 706.
 Walter Caseri, private communication.
 Schütt, Auf der Suche nach dem Stein der Weisen, pp. 293-294, 308.
 Kunckel, Collegium Physico-Chymicum, p. 277.
 Khunrath, Vom Chaos, p. 99.
 Khunrath, Vom Chaos, p. 99.
 Heinrich Khunrath, Amphitheatrum Sapientiae Aeternae, ed. Erasmus Wolfart, Hanau: Wilhelm Antonius, 1609, Section 2, p. 129; the Amphitheatrum is divided into two numbered sections, the first giving the Biblical and apocryphal verses to which the commentary of the second refers.
 Khunrath, Vom Chaos, p. 137.
 Svedberg, Methoden, p. 210.
 Basil Valentine, “Kurtzer Anhang und klare Repetition oder Wiederholung... vom grossen Stein der Uhr-alten,” in Chymische Schriften, Hamburg: Gottfried Richter, 1740, pp. 84-85.
 Claus Priesner, “Spiritus Aethereus – Formation of Ether and Theories on Etherification from Valerius Cordus to Alexander Williamson,” Ambix, Vol. 33, Part 2/3, November 1986, p. 130.
 Macquer, Chymisches Wörterbuch, Vol. 2, p. 708.
 Paracelsus, “Von den natürlichen Dingen,” in Sudhoff
(ed.), Sämtliche Werke, Vol. 2, Munich: Oldenbourg, 1930, pp. 133, 154;
priority for the discovery of diethyl ether is sometimes given to the German
doctor Valerius Cordus (1515-1544), although this has been disputed: see Ernst
Darmstaedter, “Zur Geschichte des Äthers (Diäthyläthers),” Journal für
Praktische Chemie, Vol. 119, October 1928, pp. 74-88; Priesner, “Spiritus
Aethereus,” p. 129.
 Schütt, Auf der Suche nach dem Stein der Weisen, p. 450.
 Although the Deutscher Biographischer Index, Vol. 2, München: K. G. Saur, p. 1599, lists both a “Frobenius, August Sigmund (U nach 1730), Chemiker” and a “Frobenius, Sigismund August (U 1741), Mediziner, Fachautor,” they are in fact one and the same man. The former variant of his name stems from the Allgemeine Deutsche Biographie, and although it appears to be incorrect it is the one most often utilised by scholars; the latter variant, on the other hand, is in accord with the name given in the Philosophical Transactions itself, and as this journal is the only primary source relating to this mysterious figure, I follow the rendering there. See also Poggendorff, J. C., Biographisch-Literarisches Handwörterbuch zur Geschichte der Exakten Wissenschaften, Vol. 1, Leipzig: Johann Ambrosius Barth, 1863, p. 809.
 Sigismond Augustus Frobenius, “An account of a Spiritus Vini Æthereus, together with several Experiments tried therewith,” Philosophical Transactions of the Royal Society, No. 413, 1730, p. 286.
 Frobenius, “An account of a Spiritus Vini Æthereus,” p. 284.
 Frobenius, “An account of a Spiritus Vini Æthereus,” p. 288.
 Frobenius, “An account of a Spiritus Vini Æthereus,” pp. 285-286.
 Cromwell Mortimer, “Abstracts of the original Papers communicated to the Royal Society by Sigismond Augustus Frobenius, M.D., concerning his Spiritus Vini Aethereus,” Philosophical Transactions of the Royal Society, No. 461, 1741, p. 865.
 Mortimer, “Abstracts,” pp. 869-870; Mortimer appears to imply that the original spiritus vini aethereus did not belong to this class of æthereal spirits.
 Mortimer, “Abstracts,” p. 865.
 Priesner, “Spiritus Aethereus,” p. 130.
 Aristotle, De Coelo, 270b1-270b23 (Aristotle, Vom Himmel, Munich: DTV Verlag, 1987, pp. 62-63).
 William Newman, “Decknamen or Pseudochemical Language? Eirenaeus Philalethes and Carl Jung,” Revue D’Histoire des Sciences, Vol. 49, No. 2, 1996, pp. 161, 174, 188; Principe and Newman, “Some Problems with the Historiography of Alchemy,” in William R. Newman and Anthony Grafton (eds.), Secrets of Nature: Astrology and Alchemy in Early Modern Europe. Cambridge, Ma.: MIT Press, 2001, pp. 397, 401.
 Principe, Lawrence M., The Aspiring Adept, pp. 46-47.
 Khunrath’s Christian Kabbalah stems above all from the Artis cabalisticae scriptorum, Vol. 1, of Johann Pistorius.
 Khunrath, Amphitheatrum (1595 edition), p. 21: “Quales sint autem AQUAE SUPERCELESTES; cuius generis, substantiae atque Naturae, nobis Theosophicè percontandum. Influentia, igitur, Lumine et Motu SOLIS DIVINI doctus ac ductus, in Nomine DOMINI dico, AQUAS SUPERCELESTES esse unius eiusdemque generis et substantiae, cuius erat LATEX ille aethereus incombustibiliter ardens, repertus, patrum nostrorum memoria, Patavii in Italia, in monumento vetustissimo, intra urnulam fictilem, intra duas altera ex auro altera ex argento ampullas, cuius liquoris purissimi virtute per plurimos annos lucerna haec arsit...”
 C.f. Khunrath, Vom Chaos, pp. )()(5 verso - )()(6 recto.
 Peter Apian and Bartholomeus Amantius, Inscriptiones sacrosanctae vetustatis, Ingolstadt: Peter Apian, 1534, p. 337.
 Gesner, Evonymus, p. Ai verso – Aii verso; Gesner cites the account of Apian’s Inscriptiones as proof of the antiquity of the art of distillation.
 Andreae, Fama Fraternitatis, pp. 89-91.
 Bartholomäus Korndörffer, Everburning Lights of Trithemius, Bodleian Library, MS Ashmole 1408, pp. 239-243.
 Hermolaus Barbarus, In dioscoridem Corollariorum, Köln: Johannes Soter, 1530, verse 623 (on Aquae in Commune): “Est et coelestis aqua, sive potius divina, chymistarum, quam et Democritus et Mercurius Trismegistus novere, ...modo Scythicum laticem appellantes, modo pneuma, hoc est spiritum ex aetheris natura et essentia rerum quinta: unde aurum poculentum, et iactatus ille necdum inventus philosophorum lapis et sabulum, constet.”
 Gesner, Evonymus, Ai verso – Aii verso.
 Khunrath, Amphitheatrum (1595 edition), pp. 21-22.
 Khunrath, Amphitheatrum (1595 edition), p. 17; c.f. Khunrath, Vom Chaos, p. 121.
 Khunrath, Amphitheatrum (1595 edition), p. 17: “Mercurius, h.e., Spiritus aethereus, operans pro Natura scintillarum NATURAE quibus conjungitur...”
 Khunrath, Amphitheatrum (1609 edition), Section 2, p. 196; see below, n. 182.
 Khunrath, Amphitheatrum (1595 edition), p. 22: “HOC, CELUM Empyreum, lucidissimum; imó, LUX, quam (tanquam rem Divinitati consentaneam) DEUS inhabitat inaccessibilis, 1. Timoth. 6.16. QUEM idcirco in ignea esse Essentia Divinus Plato ab Indorum Brachmanibus didicit, Quintamque Essentiam Divinitatis statuit mansionem.”
 Khunrath, Amphitheatrum (1595 edition), p. 21: “Secundò, SUPERIUS, non mixtum Elementis eorundemque superfluitatibus, sed per et in se (animatum tamen NATURA) congelavit, solidavit, corpus durum ac solidum constituit atque effecit, hoc est, firmavit... Unde Latini FIRMAMENTUM, Germani eine Veste rectè dixerunt: nam quovis ære et adamante est durior et durabilior; Celi solidissimi, quasi ære, fusi sunt, Iob. 37.18 quare nec Lucis aut Ignis sui calore, nec motus pernicitate imminutionem patitur, nedum, antè diem novissimum DOMINI, consumatur... Et fecit DEUS Firmamentum, (ut sit tanquam firmissima fornix, quam DEUS subjecit aquis, et per quam retineret eas in sublimi) divisitque aquas, quæ erant sub Firmamento, ab his quæ erant super Firmamentum.”
 Khunrath, Amphitheatrum (1595 edition), Emblem 3, Question 5; in the extended 1609 edition of the Amphitheatrum the text surrounding the third emblem in the original version of 1595 has been removed and placed as an appendix to the main body of the work. Khunrath, Amphitheatrum Sapientiae Aeternae (1609 edition), Section 2, p. 196: “Quid est Cælum? CÆLUM est SPIRITUS ÆTHEREUS corporalis, vel, corpus æthereum spirituale, corruptioni non obnoxium, totius Mundi machinam permeans: superius, VERBO DOMINI, firmatum, hinc FIRMAMENTUM; inferius, massæ sublunari, toti incorporatum: Unius eiusdemque et essentiæ et substantiæ Cælum unum, id quod inferius, et id, quod superius. Illud, tamen, labore Physicochemiæ sagaci, in usum hominum, ad sensum potest manifestari atque tractari.” According to the 1595 version of the Amphitheatrum, the universal prima materia is composed of the Paracelsian (physico-chemist’s) Sulphur and Salt rather than the Sulphur and Mercury given in Vom Chaos; nevertheless, the latter work also refers to this ‘Mercury’ as a ‘salt’ (p.142).
 Khunrath, Amphitheatrum (1595 edition), p. 22: “HOC, CELUM SECUNDUM, sublime; Regio purè ætherea. HOC, Solem, Lunam et Stellas habet; revera etiam PRIMUM et Inferius (suo modo) astra sua: id quod sciunt atque testantur Sapientes. Motu harmoniaco sivè sympathico (erga se invicem) movetur utrumque: id quod inferius, sicut id quod est superius, et contra;” Khunrath, Amphitheatrum (1595 edition), Emblem 3, Question 4 (= Khunrath, Amphitheatrum (1609 edition), Section 2, p. 195): “UNUS (essentia et numero) hic DEI Spiritus est; una, Universitatis perspicuæ et corporeæ huius unius, Anima catholica, tamen, h.e. multiformis (Sap. 7,22. Ephes. 3,10) et variæ eius radii atque SCINTILLÆ, per totius ingentem, materiei primæ massæ, molem, hinc inde dispersæ ac dissipatæ...”
 Khunrath, Amphitheatrum (1595 edition), Emblem 3, Question 4 (= Khunrath, Amphitheatrum (1609 edition), p. 195): “RUACH ELOHIM, est SPIRITUS, spiraculum, anhelitus äåÈäéÔ sancti, sanctus; Vapor virtutis DEI omnipotentis atque omni tenentis, et EMANATIO quædam, emmisiovè, fœcunditatis vitalis, primi summique motoris, vivifica atque virtuosa, è profundissimo, Divinitatis suæ recessu; IDEARUM, videlicet, sivè Exemplarium, Specierum, Rationum seminariarum, primordialium et radicalium, voluntatum opificum et causarum effectricum, in ARCHETYPI, opificis summi, mente (äî ëÀä® Hhochmah in SAPIENTIA, Bonitate eius, causante eas) conceptarum atque præexistentium, rerum omnium, in Mundo, postea futuro, producendarum et fiendarum.” The doctrine of signatures is the subject of Khunrath’s doctoral theses, De Signatura Rerum Naturalium Theses, Basel: Oporinianis, 1588; in his Amphitheatrum (1595 edition), p. 17, Khunrath boasts that he publically defended this doctrine for the doctoral degree he received on the 24th of August 1588 in Basel, and that he was the first to do so after Paracelsus, as Giambattista della Porta’s Phytognomonica (1588) was not known in Germany at that time.
 Khunrath, Amphitheatrum (1595 edition), Emblem 3, Question 6 (= Khunrath, Amphitheatrum (1609 edition), p. 197): “RUACH ELOHIM (descendendo demittendoque se per circumferentias partesque abditissimas omnes, et dispergendo in imum vel meditullium, Scintillas radiosve fœcunditatis suæ) ad CENTRUM usque penetrabat, in ENS illud CREATUM, totum: massamque illam sive molem ingentem, rudem, (&Mac215;ÁÏÓ) confusam atque informem, Mundi futuri seminarium, sive materiam lutosam, VIRGINEAM, (nondum enim neque conceperat, neque produxerat antea) FORMA (semetipso) sic informavit, et ANIMA animabat, imprægnabatque purissima...”
 Ficino, De Vita 3.3.
 Khunrath, Amphitheatrum (1595 edition), p. 17.
 Khunrath, Vom Chaos, pp. 40-41.
 Khunrath, Amphitheatrum (1609 edition), Section 2, p.131: “Mirabile DEI Mirabilis Laboratorium Macro Cosmicon, Natura praesidente aut Laborante, perpetuum, Catholicon.”
 Khunrath, Lux Lucens in Tenebris, pp. 11-12: “Solviret die Cörper in unser quecksilber welches ist das waßer der Kunst, und wird im bestendig waßer. Den gleich wie in erschaffung der welt alles waßer gewesen, und der Geist Gottes darauff geschwebt: Also ist es auch in anfange dieses werckes in der solution, den es steiget auf und abwerts so lange, biß es seinem Cörper solviret hat...”
 Khunrath, Vom Chaos, p. 40; c.f. Aristotle, De Anima, 2.1, 412a-413a (Aristotle, Über die Seele, trans. Horst Seidel, Hamburg: Felix Meiner Verlag, 1995, pp. 59-65).
 One finds them, for instance, in the works of Fludd, Maier and van Helmont.
 From Roger Bacon, The Mirror of Alchimy, London: Richard Olive, 1597, p. 17.
 From Roger Bacon, The Mirror of Alchimy, London: Richard Olive, 1597, p. 16.
 Hermes Trismegistus, “Hermetis Trismegisti Tractatus Aureus,” in William Salmon (ed.), Medicina Practica: or, Practical Physick. London: Printed for T. Howkins, J. Taylor and J. Harris, 1692, p. 244.
 Carl Gustav Jung, “Mysterium Coniunctionis,” The Collected Works of C. G. Jung, Vol. 14, trans. R. F. C. Hull, Princeton: Princeton University Press, 1976, p. 228.
 Michael Maier, De Circulo Physico, Quadrato, Oppenheim: Lucas Jennis, 1616, p. 7: “Utque Deus Soli, Sol auro, hoc denique cordi/ Vim dat...”; Hélène Metzger, “L’évolution du règne métallique d’après les alchimistes du XVIIe siècle,” Isis, Vol. 4, 1922, pp. 466-482.
 Principe and Newman, “Some Problems with the Historiography of Alchemy,” p. 397.
 C.f. William R. Newman, “The Corpuscular Theory of J. B. Van Helmont and its Medieval Sources,” Vivarium, Vol. 31, 1993, pp. 161-191.
 Carl Gustav Jung, “Psychology and Alchemy,” The Collected Works of C. G. Jung, Vol. 12, trans. R. F. C. Hull, London: Routledge and Kegan Paul, 1968, p. 476.
 Principe and Newman, “Some Problems with the Historiography of Alchemy,” p. 406.
 On this matter see Principe and Newman, “Some Problems with the Historiography of Alchemy,” and their article “Alchemy vs. Chemistry: The Etymological Origins of a Historiographic Mistake,” Early Science and Medicine, Vol. 3, No. 1, 1998, pp. 32-65.
 Unpublished manuscript; c.f. Principe and Newman, “Some Problems with the Historiography of Alchemy,” p. 387.
 C.f. Anthony Giddens, Modernity and Self-Identity, Stanford: Stanford University Press, 1991, p.77.
 On this subject, see The Quest for the Phoenix: Spiritual Alchemy and Rosicrucianism in the Work of Count Michael Maier (1569-1622), Berlin: de Gruyter, 2003.
 Jung, “Psychology and Alchemy,” p. 218
 Newman, “Decknamen or Pseudochemical Language?,” p. 165.
 Georg Wilhelm Wegner (‘Tharsander’), Adeptus Ineptus, Oder Entdeckung der falsch berühmten Kunst ALCHIMIE genannt, Berlin: Ambrosius Haude, 1744, p. 80.