Dream 2047, April 2000 Issue

History of Science

FROM ALCHEMY TO CHEMISTRY (Part-I)

Ben Jonson's The Alchemist appeared in 1610. As Jonson hinted the art of alchemy was of great antiquity. It is a long journey from the forgotten and bizarre world of alchemy of the antiquity to chemistry which 'allows us to calculate the interaction of atoms....' The science of chemistry had also other sources like natural philosophy, medicine and metallurgy - the common features of which were recognised by Aristotle (384-322 B.C.) and his student Theophrastus (c.372-c.287BC.) Theophrastus' On Stones written about 300 B.C. is the earliest surviving trcatise on pratical chemistry.

Alchemy also drew most of its contents from natural philosophy, medicine and metallurgy but then it also brought practices and beliefs from various magico-religious lores. The supposedly direct relation between chemistry and alchemy lies in the fact that to start with alchemy in every culture made matter and its changes its central preoccuption. However, alchemy ended in an occultism or esoteric alchemy which was not concerned with the science of matter.

It is to be emphasised that chemistry did not directly emerge from alchemy. In fact the direct influence of alchemy on the emergence of chemistry, as a distinct scientific discipline, seems to have been minimal. However, its indirect contribution was immense. It is through alchemy that chemistry gained some semblance of independence in the spectrum of the arts and sciences. Further, medicinal chemistry as a result of the introduction of new methods of preparing medicines by traditionally alchemical practices was able to earn a secure and significant place in science in the European Renaissance.

The long, intriguing and enigmatic history of alchemy had everything in it - romance, adventure, fraud, trickery, religion, mysticism, tragedy, comedy, poetry, humour, scientific inquiry and skillful technology. There isn't a more impressive or romantic chapter in the history of science than the period spent on the quest of the Philosopher's Stone - the ultimate goal of alchemy. For more than 2000 years people of all hues struggled and toiled in the dark corners to 'hitt the marke', as alchemists would like to call. The practitioners of alchemy were not all charlatans. They ranged from kings, popes, emperors, great scientists and thinkers to minor clergy, parish clerks, metal-smiths and dyers. Practitioners of alchemy included: Roger Bacon (c.1214-1292), St. Thomas (1st century AD), Sir Thomas Browne (1605-82), John Evelyn (1620-1706), Sir Isaac Newton (1642-1727), Charles II (1839-88), Herakleios or Heraclius of Byzantine (c.575-641), James IV, king of Scotland (1473-1513), and many others.

Egypt, or khem, the country of dark soil has often been pictured as the motherland of chemistry and the 'art of the dark country' became known to Islam as al khem, and through Islam to the Western World as alchemy. J.R. Partington in his Origins and Development of Applied Chemistry states: 'The hieroglyphic name for Egypt, supposed to represent a heap of charcoal, a crocodile's tail or a piece of fish skin, is zemi or chemi, with the meaning black - the black land; chemia is a rare form'.

Man's attempts to produce gold artificially and to explain its occurrence in the Earth's crust has played an important role in developing chemistry. The origin of alchemy has been linked to early evidence of the importance attached to gold. (In fact many writers have interpreted alchemy as the pretended art of transmuting 'base' metals into gold). Justus Von Liebig (1803-73), one of the most remarkable chemists of the nineteenth century, wrote: "The most lively imagination is not capable of devising a thought which could have acted more powerfully and constantly on the minds and faculties of men, than that very idea of the Philosopher's Stone. Without this idea, chemistry would not now stand on its present perfection... In order to know that the Philosopher's Stone did not really exist, it was indispensable that every substance accessible...should be observed and examined...But it is precisely in this that we perceive the almost miraculous influence of the idea. The strength of opinion could not be broken till science had reached a certain stage of development." In fact Liebig did not consider alchemy something different from chemistry. He wrote: "Alchemy was never at any time anything different from chemistry. It is utterly unjust to confound it, as is generally done, with the gold-making of the sixteenth and seventeenth centuries... Alchemy was a science, and included all these processes in which chemistry was technically applied." There was no doubt that modern chemistry gradually emerged out of the hard work of generations of alchemists. Francis Bacon (1561-1626) wrote in his De Augmentis Scientiarum: "Alchemy may be compared to the man who told his sons that he had left them gold buried somewhere in his vineyard; where they by digging found no gold, but by turning up the mould about the roots of the vines, procured a plentiful vintage. So the search and endeavours to make gold have brought many useful inventions and instructive experiments to light."

In a wider sense alchemy was certainly the chemistry of the Middle Ages, as Liebig had pointed out (quoted above). But then alchemy was not just a branch of applied (or pure) science which gave rise to modern chemistry. In its broadest sweep, alchemy should be viewed as a system of philosophy 'which claimed to penetrate the mysteries of life as well as the formation of inanimate substances.' M. A. Atwood in her book, A Suggestive Inquiry into the Hermetic Mystery' wrote: "Hermetism, or its synonym Alchemy, was in its primary intention and office, the philosophic and exact science of the regeneration of the human soul from its present sense-immersed state into perfection and nobility of that divine condition in which it was originally created. Secondarily and incidentally...it carried with it a knowledge of the way in which the life-essence of things belonging to the sub-human kingdoms - the metallic genera in particular - can, correspondingly, be intensified and raised to a nobler form than that in which it exists in its present natural state."

John Read in his Prelude to Chemistry: An Outline Of Alchemy - Its Literature and Relationship, wrote: "...alchemy was something more than an ancient art which gave rise after long centuries to the modern science of chemistry. It was a complex and indefinite aggregation of chemistry, philosophy, religion, occultism, astrology, magic, mythology, and many other constituents. It was a strange blend of logical thinking and mystical dreaming, of sound observation and wild superstition, of natural and moral ideas, of objective facts and subjective conclusions."

Our aim is not to glorify alchemy or to argue for its acceptance as a true branch of science (which in any case it was not). However, any one in search of the true significance of alchemy cannot but 'absorb something of the romance and wistfulness of the struggle' which continued for ages of this so-called 'Divine Art' after the non-existant. 'Pray, read, toil - and then thou shalt find', was the guiding motto of the alchemists. Alchemy may be defined as the prayerful search after truth in the light of the principle of the unity of matter.

Before alchemy various branches of technology like metallurgy, ceramics, glass-making, dyeing and colouring, weaving, brewing and the preparation of drugs, poisons and cosmetics had reached a high degree of accomplishment. Like modern science alchemy had also its own theories. However, these were vague and not defined systematically. Interpreters were free to interpret them to suit their own whims. The main physical theory of alchemy was the four elements or 'simple bodies' viz., earth, fire, water and air and the four primary qualities viz., hot, cold, dry and moist - a theory developed by the Greek philosophers by about the fifth century BC. Aristotle conceived of these elements and their qualities as emphasising the unity of matter amidst all the changes.

The basis of everything, according to Aristotle, is the primary matter or first matter (prote hyle), on which are impressed the specific qualities that give an individual substance its characteristic form. For example the primary matter, a potential one, would become earth with the pair of primary qualities, cold and dry; water with cold and wet; fire with hot and dryness; and air with hot and wetness. Aristotle explained the theory in the following way : "The elementary qualities are four, and any four terms can be combined in six couples. Contraries, however, refuse to be coupled; for it is impossible for the same thing to be hot and cold, or moist and dry. Hence it is evident that the couplings of the elementary quantities will be four; hot with dry and moist with hot, and again cold with dry and cold with moist, and these four couples have attached themselves to the apparently simple bodies (fire, air, water and earth) in a manner consonant with theory. For fire is hot and dry, whereas air is hot and moist (air being a sort of aqueous vapour) and water is cold and moist, while earth is cold and dry. Then the differences are reasonably distributed among the primary bodies, and the number of the latter is in consistence with theory."

The four material elements - earth, air, fire and water - were pictured as originating by pair-wise conjunctions of the four qualities, and shown in Fig. 1.

To the early alchemists of the Hellenistic culture of Alexandria in Egypt the theory of four elements and four qualities held out the possibility of transmuting base (less precious ones) metals into gold or silver by changing the qualities. To them as all bodies were composed of the four elements in different proportions, one body could be changed or transmuted, into another by changing the proportion of the elements present. The idea of transmutation was correlated with the idea of a 'primary matter' from which all things emerged.

Conception of the 'Five Elements' can be found in India and China as early as 1500 BC. In fact as someone has said, it was 'one of those crude physical theories which is enunciated and accepted by races the most diverse in character, country, faith, destiny. There is great oneness in the human mind in matter of broad principles in crude chemical ideas.'

Among the four qualities colour was the most perceptible one and so it was natural to try to change the colour of a matter like copper or tin to that of gold or silver. And a change in qualities meant emergence of a new metal.
As described by A.J. Hopkins, the four fundamental beliefs which had had great influence on alchemists were:

1. Hylozonism: all Nature is like man, alive and sensitive.
2. That the great universe of Sun and stars, the "macrocosm", is guided by the same laws which obtain on the earth (and for) the "microcosm" (of man's body).
3. Astrology: the stars influence and foretell the course of events on this earth.
4. Animism: any event apparently spontaneous is really due to some personality - fairy, wood spirit, hobgoblin etc.

Alchemists relied mainly upon deductive reasoning based on two a priori assumptions - the unity of matter and the existence of a Philosopher's Stone.
Alchemy is said to have arisen in the temples of ancient Egypt and China. And from beginning to its end alchemy remained bound up with religious beliefs. In fact some of the alchemical strands may be traced back to ancient mythological systems other than those found in the forms of religion practiced by Jews, Christians, Gnostics, neo-Platonists, Muslims, Hindus and Taoists/Buddhists.

Medieval works on alchemy abound in references to the sulphur-mercury theory. According to this theory Nature brings forth all metals from mercury mingled with its own sulphur. When mercury and sulphur are perfectly pure and combine in the most appropriate natural equilibrium then the product is the most perfect of metals that is gold. Different kinds of metal exist because sulphur and mercury are not always pure and that they do not always unite in the same proportion. So the defects in purity and proportion lead to the formation of 'base' metals but since the base metals are also essentially composed of the same constituents as gold or silver the accidents of combination may be rectified.

To alchemists achievement of the Stone was the greatest and final goal. To them it represented imperfect man's search for perfection. The fundamental idea of the Philosopher's Stone was expressed by Arnold of Villanova: "That there abides in nature a certain pure matter, which, being discovered and brought by art to perfection, converts to itself proportionally all imperfect bodies that it touches". We really do not know where and when the concept of the Philosopher's Stone developed. The idea of the Philosopher's Stone in one form or the other was the main source of inspiration of all alchemists of whatever race or station.

Some of the ancient figures from whose work and philosophy the alchemists drew inspiration were:

Ostanes or Osthanes (before 300BC) is often mentioned as a pioneer in magic and alchemy.
Bolos of Mende (300 BC) a student of Ostanes was the author of Physica et Mystica, the sacred book of Greek alchemy. His writing combined matter-of-fact information with folk-lore and superstition.

Mary 'the Jewess' is credited with invention of several types of apparatus for distillation and sublimation which revolutionised alchemy. She lived a little before Bolos and also was supposed to be a student of Ostanes. This enigmatic woman alchemist to whom there are so many references in alchemical writings from the Alexandrian period onwards is often identified with Miriam, the sister of Moses.

Agathodaimon, believed to be an associate of Mary, 'the Jewess' of 'school' is considered to be an important author of the Greek alchemical texts.

Hermes Trismegistus, 'the Thrice-great Hermes' is regarded as 'father' of alchemy. Alchemy is also known as Hermetic Art. However, he is better known in antiquity as an astrologer.

Posidonius (c.135-c.51BC), one of the most remarkable philosophers of antiquity, was head of the Stoic School in Athens. He came from Apamea in Syria. He is said to have brought magic and astrology to philosophy.

Apollonius of Tyana, a travelling philosopher of the first century AD was an authority on matter. He was born in Cappadocia and was a sage of the Neopythagorean sect.

An anonymous Egyptian writer of the 3rd century, who authored the Leyden papyrus, is believed to have been a practicing goldsmith whose recipe book was interned with him.

Zosimos or Zosimos of Panopolis (3rd or 4th century AD) is believed to be one of the important authors of early Greek manuscripts on alchemy.

It is widely acknowledged that the roots of Arabic alchemy lie in Greek science. Alchemy came to the Muslims originally from Alexandria, one of the greatest centres of Hellenistic culture. One of the exponents of Islamic alchemy and also the most celebrated one was Jabir ibn Hayyan (c.721-c.815) also known as Geber in the western world. Jabir ibn Hayyan means Jabir the son of Hayyan. This name is often followed by titles like Al-Azdi, Al-tusi, Al-Kufi and Al-Sufi. Al-Azdi implies that he was a member of the Azd tribe of South Arabia. Al-Kufi probably indicates that he belonged to that part of the Azd tribe which domiciled at Kufa. Al-Sufi signifies that he belonged to the community that cultivated a variety of mysticism known as Sufism. The Sufism which was so called from the Arabic Suf, (meaning wool), because the early members of this sect used to wear a coarse garment made of this material. He lived at the time when the Arabic empire under Harun al-Rashid (766-809), the fifth Abbasid Caliph, of Arabian Nights fame was at the height of its glory.

The most important groups of treatises in the Jabirian corpus are the Hundred and Twelve books; The Seventy Books; The Ten Books of Rectifications and The Book of the Balances (Kitab al-Mawazin). The most important contribution of Jabir to alchemical thought was sulphur-mercury theory. Jabir believed that under the influence of planets metals where formed in the earth by the combination the sulphur (which would provide hot and dry natures) and mercury (providing the cold and moist natures). It was an original contribution and widely accepted by later generations of alchemists. The theory survived until the rise of the phlogiston theory of combustion towards the end of the seventeenth century. Jonson's alchemist, Subtle, gives a revealing summary of the sulphur-mercury theory as interpreted in the beginning of the seventeenth century.

Jabir classified minerals into three groups: i. Spirits or substances which are entirely vaporised on heating.
This category included sulphur, arsenic, mercury, camphor and sal ammoniac.
ii. Metals, or fusible substances that are malleable, sonorous and possess a lustre. Jabir recognised seven metals - gold, silver, lead, tin, copper, iron, and khar sini or Chinese iron - a metal which is thought to be an imported alloy of complex composition.
iii. Mineral substances whether fusible or not are not malleable and may be powdered. They do not vaporise entirely in fire. This group is further sub-divided into eight groups on the basis of whether they are : (a) stony or not-stony, (b) pulverisable or non-pulverisable and (c) fusible or not-fusible
Jabir made a systematic recording of chemical observations that he found interesting or useful. We find description of many useful chemical processes like:
1. Preparation of nitric acid
ii. preparation of steel and refinement of other metals
iii. dyeing of cloth and leather
iv. making varnishes to water proof cloth and protect iron from rusting
v. mordanting fabrics with alum

Jabir described ammonium chloride and showed how to prepare white lead. He prepared strong acetic acid by distilling vinegar. It may be noted that acetic acid was the strongest acid known to the ancients. Jabir also prepared weak nitric acid which, potentially, at least, was much stronger.

AnotherJabirian innovation is the use of elixirs derived from the distillation of organic materials. This marked the transition of Arabic alchemy from a technological to a medical orientation.

A large corpus of alchemical literature both in Arabic and Latin, is ascribed to Jabir (Geber in Latin). However, we really do not know how much of their contents is to genuine work of Jabir.

Jabir's style of writing was relatively straight forward.
Some of the broad conclusions that may be drawn from the scholarly works of 'Jabir' are:

1.The Latin works of alchemy attributed to Geber have no corresponding Arabic versions.

2.The Latins of the middle ages knew very little about a large body of Arabic works on alchemy attributed to Jabir.

3. It is almost certain that Jabir was not the author of all the works in Arabic attributed to him. A major part of Arabic Jabirian alchemy is part of the encyclopaedic production of another Islami sect, the Ikhwan al-safe, the Brethren of Purity, which flourished in Basra in the second half of the tenth century.

4. Jabir may never have existed at all.

Another outstanding Arabic alchemist was Abu Bakr Muhammad ibn Zakariya Al-Razi (860-925), called Rhazes in Latin. He was one of the greatest Muslim physicians. He is also regarded as a tenth century Boyle. Al-Razi, who was a great critic of established religion of middle ages wrote on most of the sciences, then recognised, including mathematics and metaphysics, but what has survived is his work on medicine and alchemy. His most important work on alchemy is the Book of the Secret of Secrets (Kitab Sirr al-asrar).
From the point of view of chemistry, al-Razi's most important innovation was his attempt to classify the 'earthy' substances. He established the classes of salts and metallic (al-Razi's stones). He introduced a new class of 'artificially proposed substances' - lead oxides, copper acetate, lead carbonate and some 'uncertainly-identifiable' oxides and slags.

Another important achievement of al-Razi in alchemy was his systematisation of alchemical procedures. He worked out a sequence of laboratory operations consisting of purification-separation into fine parts and removal of water.

In the writings of Arabic alchemists we find processes for producing sharp waters which eventually led to the discovery of the mineral acids viz. sulphuric acid, hydrochloric acid and nitric acid.

The works of Jabir and Al-Razi which are noted for their clarity and absence of mysticism and allegory exerted a great influence on later generation of alchemists, both Arabic and of the West. Both Jabir and al-Razi while being practicing chemists believed in the possibility of transmutation. But Abu Ali-At Husain ibn Abdullah ibn Sina (980-1037), called Avicenna in the West, the greatest physician of Islam, doubted the reality of transmutation. His Cannon of medicine remained a standard work for six centuries and it was studied both in the East and the West. His observations on chemistry are included in his book the Kitab al-Shifa (the Book of the Remedy)

- Subodh Mahanti