In Aristotle's time, Alexander the Great of Macedon (a kingdom north of Greece) conquered the vast Persian Empire. Alexander's empire broke up after his death in 323 B.C., but Greeks and Macedonians remained in control of large areas of the Middle East. For the next few centuries (the Hellenistic period") there was a fruitful mingling of cultures.
Ptolemy, one of Alexander's generals, established a kingdom in Egypt, with the city of Alexandria (founded by Alexander) as his capital. In Alexandria, Ptolemy and his son (Ptolemy II) established a temple to the Muses (the "Museum") which served as what we would today call a research institution and university. Attached to it, the greatest library of ancient times was built.
Egyptian mastery of applied chemistry met and fused with Greek theory, but the fusion was not entirely to the good. Chemical knowledge in Egypt was intimately connected with the embalming of the dead and with religious ritual. To the Egyptians the ibis-headed god of wisdom, Thoth, was the source of all chemical knowledge. The Greeks, generally impressed by the superior knowledge of the Egyptians, identified Thoth with their own Hermes and accepted much of the mysticism.
The old Ionian philosophers had divorced religion and science. This new union in Egypt seriously interfered with further advance in knowledge.
Because the art of khemeia seemed so closely related to religion, the common people rather feared the practitioners as adepts of the secret arts and as partakers of dangerous knowledge. (The astrologer with his feared knowledge of the future, the chemist with his awesome ability to change substances, even the priest with his hidden secrets concerning the propitiation of the gods and with the ability to call down curses, served as models for folk-tales of magicians, wizards, and sorcerers.)
Those who where the object of these fears did not always resent them, but at times rather encouraged them as increasing their own sense of power, and perhaps their security as well. Who would care to offend a magician, after all?
This public respect or fear encouraged workers in khemeia to couch their writings in mysterious and obscure symbolism. The very obscurity added to the sense of secret knowledge and power.
As an example, there were seven heavenly bodies considered "planets" ("wanderers") because they were continually changing their position with reference to the starry background. There were also seven known metals: gold, silver, copper, iron, tin, lead, and mercury. It seemed tempting to match them. There came a time when gold would be regularly referred to as "the Sun", silver as "the Moon", copper as "Venus", iron as "Mars", tin as "Jupiter", lead as "Saturn", and mercury as "Mercury". Chemical changes could then be referred to in mythological fashion.
There are still reminders of this time. One rather old-fashioned name for the chemical now called silver nitrate is "lunar caustic", a clear indication of the old connection of silver and the moon. The metal mercury gets its modern name from the planet Mercury. The true ancient name was hydrargyrum ("liquid silver"), and the old English word was the nearly identical "quicksilver".
This more or less deliberate obscurity served two unfortunate purposes. First, it retarded progress since each worker in the field was kept in ignorance, or at least in uncertainty, as to what others were doing, so that no man could profit by another's mistakes or learn from another's brilliance. Secondly, it made it possible for any quack and faker to present himself, provided he spoke obscurely enough, as a serious worker. The knave could not be distinguished from the scholar.
The first important worker in Greek-Egyptian khemeia that we know by name was Bolos of Mendes (c.200 B.C.), a town in the Nile delta. In his writings, he used the name Democritus so that he is referred to as "Bolos-Democritus" or sometimes as the "pseudo-Democritus".
Bolos devoted himself to what became one of the great problems of khemeia, the changing of one metal into another and, particularly, the changing of lead or iron into gold (transmutation).
The four-element theory would make it seem that the various substances of the universe differed only in the nature of the elemental mixture. This hypothesis would be true whether one accepted the atomist view or not, since the elements could mix as atoms or as continuous substance. Indeed, there seemed reason to think that even the elements themselves were interchangeable. Water seemed to turn to air when it evaporated, and the air turned back to water when it rained. Wood, if heated, turned to fire and vapors ( a form of air) and so on.
Why should any change, then, be considered impossible? Surely, it was only a matter of finding the proper technique. A reddish rock could be converted to gray iron through a technique that had not yet been discovered in the time of Achilles, who had to wear bronze armor. Why, then, should not gray iron be further converted to yellow gold by means of some technique that had not yet been discovered in the time of Alexander the Great?
Many chemists throughout the centuries have honestly striven to find the technique for producing gold. Some, however, undoubtedly found it much easier and far more profitable merely to pretend to find the technique and to trade on the power and reputation this gave them. This sort of fakery continued right on into modern times (That is not our focus).
Bolos, in his writings, apparently gave the details of techniques of making gold, but this may not actually have represented fakery. It is possible to alloy copper with the metal zinc, for instance, to form brass, which has the yellow color of gold. It is quite likely that the preparation of gold-colored metal would be the equivalent, to some of the ancient workers, of forming gold itself.
However, the art of khemeia went downhill during Roman times, along with a general decay of Greek learning. After A.D. 100 virtually nothing new was added, and there was a rising tendency to turn to ever-more mystical interpretations of the earlier writers.
About A.D. 300, for instance, an Egyptian-born writer, Zosimus, wrote an encyclopedia of twenty-eight books covering all the knowledge of khemeia that had accumulated in the previous five or six centuries, and there was very little of value in it. To be sure, one can find an occasional passage with something novel in it, like that seeming to refer to arsenic, and Zosimus seems to have described methods for forming lead acetate and to have known the sweet taste of that poisonous compound. (It is called "sugar of lead" to this day.)
The final blow came through fear. The Roman emperor Diocletian actually feared that khemeia might successfully produce cheap gold and destroy the shaky economy of the declining Empire. In Zosimus's time, he ordered writings on khemeia to be destroyed, which is one explanation of why little remains to us.
Another reason is that, with the rising tide of Christianity, "pagan learning" came into disfavor. The Alexandrian Museum and Library were badly damaged as a result of Christian riots after A.D. 400. The art of khemeia, with its close relationship to the ancient Egyptian religion, was particularly suspect and it virtually went underground.
In one respect, Greek learning left the Roman world altogether. Christianity had been broken up into sects, one of them called Nestorians, because they followed the teachings of a Syrian monk, Nestorius, who lived in the fifth century. The Nestorians were persecuted by the orthodox Christians of Constantinople, and a number of them fled eastward into Persia. There the Persian monarchs treated them with great kindness (possibly in the hope of using them against Rome).
The Nestorians brought Greek learning with them to Persia, including many books on alchemy. The peak of their power and influence came about A.D. 550.
In the seventh century, however, the Arabs came on the scene. Hitherto, they had been isolated on their desert peninsula, but now, stimulated by the new religion of Islam, founded by Mohammed, they burst outward in all directions. Their conquering armies took over vast areas of western Asia and northern Africa. In A.D. 641 they invaded Egypt, and after quick victories occupied the land, and over the next years they inflicted the same fate on all Persia.
In Persia, particularly, the Arabs met with what remained of the tradition of Greek science and were fascinated. A highly practical encounter may have encouraged this view, too. In A.D. 670, when they besieged Constantinople (the largest and strongest city in Christiandom), they were driven off by "Greek fire", a chemical mixture that burned hotly with a fire that could not be put out with water and that destroyed the wooden ships of the Arabic fleet. According to tradition it was prepared by Callinicus, a practitioner of khemeia who had fled his native Egypt (or perhaps Syria) ahead of the Arabic armies.
In Arabic, khemeia became al-kimiya, the prefix al being their word for "the". The word was eventually adopted by Europeans as (in English) al-chemy, and those who worked in the field were alchemists. The term alchemy is applied now to the entire course of chemical history from about 300 B.C. to A.D. 1600, a period of nearly two thousand years.
Between A.D. 300 and A.D. 1100 chemical history in Europe is virtually blank. After A.D. 650 the preservation and extension of Greek-Egyptian alchemy were entirely in the hands of the Arabs and remained there for five centuries. Traces of this period remain in the number of chemical terms that are derived from Arabic: alembic, alkali, alcohol, carboy, naphtha, zircon, and others.
The best of Arabic alchemy came at the start of the period of their domination. Thus, the most capable and renowned of the Moslem alchemists was Jabir ibn-Hayyan (c.760-c.815), who was known to Europeans, centuries later, as Geber". He lived at the time when the Arabic empire (under Haroun-alRaschid of Arabian Nights fame) was at the height of its glory.
His writings were numerous and his style was relatively straightforward. (Many of the books bearing his name may have been written by later alchemists and attributed to him). He described ammonium chloride and showed how to prepare white lead. He distilled vinegar to obtain strong acetic acid, which had been the strongest acid known to the ancients. He even prepared weak nitric acid which, potentially at least, was much stronger.
Jabir's greatest influence lay in his studies in connection with the transmutation of metals. It seemed to him that mercury was the metal par excellence, since its liquid nature made it appear to have the least admixture of earthiness. Then sulfur seemed to possess the remarkable property of combustibility (and, further, possessed the yellow color of gold). It seemed to Jabir that the different metals were made up of different mixtures of mercury and sulfur, and it remained only to find some material that would facilitate the mixture of mercury and sulfur in the proper proportions to produce gold.
Ancient tradition held that such transmutation promoting substance was a dry powder. The Greeks called it xerion from their word for "dry". The Arabs changed this to al-iksir and to the Europeans it eventually became elixir. As a further testament to its supposed dry, earthy property, it was commonly called, in Europe, the philosopher's stone. (Remember that as late as 1800, a "philosopher" was what we now call a "scientist".)
The amazing elixir was bound to have other marvelous properties as well, and the notion arose that it was a cure for all diseases, and might very well confer immortality. Hence, one spoke of the elixir of life, and chemists who tired of the pursuit of gold could pursue immortality instead - also in vain.
In fact, for centuries afterward, alchemy flowed along two mainly parallel paths; a mineralogical one in which gold was the prime goal, and a medical one in which eternal life was sought.
Following Jabir, and with almost his skill and later reputation, was the Persian alchemist Al-Razi (c.850-c.925), known to Europeans later as "Rhazes". He, too, carefully described his work, preparing plaster of Paris, for instance, and describing the manner in which it could be used to form casts holding broken bones in place. He also studied and described metallic antimony. To mercury (which was volatile - that is, would form a vapor when heated) and to sulfur (which was inflammable) he added salt as a third principle in the composition of solids generally, for salt was neither volatile nor inflammable.
Al-Razi (Rhazes) was more interested in medicine then Jabir had been, and this drift toward the medical aspects of alchemy continued with the Persian, Ibn-Sina (979-1037), who is much better known as Avicenna, the Latinized corruption of his name. Avicenna was, indeed, the most important physician between the time of the Roman Empire and that of the rise of modern science. He had learned enough from the failures of centuries to doubt whether the formation of gold from other metals was possible. In this, he was, and remained, an exception among alchemists.
Revival in Europe
Arabic science declined rapidly after Avicenna. Times were unsettled in the Islamic world and grew more unsettled still as a result of the invasions and military victories of the comparatively barbaric Turks and Mongols. The palm of scientific leadership left the Arabs after three centuries, never to return. It passed to western Europe.
The western Europeans had their first relatively peaceful and intimate contact with the Islamic world as a result of the Crusades. The First Crusade was launched in 1096, and western Christians conquered Jerusalem in 1099. For nearly two centuries afterward, a Christian realm existed on the Syrian coast, like a small island in the Moslem sea. There was a certain fusion of culture, and a drizzle of Christians returning to western Europe brought with them a certain appreciation of Arabic science. In the same period, the Christians in Spain were gradually retaking the territory that had been lost to Islam in the early eighth century. In so doing, they, and Christian Europe generally, gained a further notion of the brilliant Moorish civilization that had grown up in Spain.
Europeans learned that the Arabs possessed books of great learning which had been translated from the Greek originals - the works of Aristotle, for instance - as well as their own productions, such as the works of Avicenna.
Despite a certain reluctance to handle the works of what seemed a deadly and inveterate enemy, the movement grew to translate these works into Latin to make them available to European scholars. The French scholar Gerbert (c.940-1003), who became Pope Sylvester II in 999, was an early encourager of this movement.
The English scholar Robert of Chester (fl. 1140-50) was among the first to translate an Arabic work of alchemy into Latin, completing the task in 1144. Others followed, and the greatest of the translators was the Italian scholar Gerard of Cremona (c.1114-87). He spent much of his life in Toledo, Spain, which had been taken by Christian forces in 1085. He translated ninety-two Arabic works, some of them extremely long.
Beginning about 1200 it became possible for European scholars to absorb the alchemical findings of the past and to attempt to advance beyond them, encountering, of course, as many or more blind alleys as broad avenues of progress.
The first important European alchemist was Albert of Bollstadt (c.1200-80), better know as Albertus Magnus ("Albert the Great"). He studied the works of Aristotle intensively, and it was through him that Aristotelian philosophy grew so important to the scholarship of the later Middle Ages and of modern times.
Albertus Magnus, in the course of reporting his alchemical experiments, described arsenic so clearly that he sometimes receives credit for the discovery of that substance although, in impure form at least, it was probably known to earlier alchemists.
A contemporary of Albertus Magnus was the English scholar and monk Roger Bacon (1214-92), who is best known today for his clearly expressed belief that in experimentation and in the application of mathematical techniques to science would lie the best hope for progress. He was right, but the world was not yet quite ready.
Bacon attempted to write a universal encyclopedia of knowledge and in his writings produced the earliest description of gunpowder. Bacon is sometimes thought of as the discoverer of gunpowder, but he wasn't; the real discoverer is unknown.
In time gunpowder helped to destroy the medieval order of society by giving armies a means to level castle walls, and the man on foot a chance to shoot down a horseman in armor. It was the earliest symbol of the technological proficiency that was to lead European armies to the conquest of the other continents during the five centuries from 1400 to 1900, a conquest that is being reversed only in our own lifetimes.
Alchemy in more mystic vein is to be found in works attributed to the Spanish scholars Arnold of Villanova (c.1235-c.1311) and Raymond Lully (1235-1315), though it is doubtful that they really were the authors. These writings lean heavily on transmutation, and Lully was even supposed (by tradition) to have manufactured gold for the wastrel Edward II of England.
The most important of the medieval alchemists is not known by name, for he wrote under that of Geber, the Arabic alchemist of six centuries before. Nothing is known of this "false Geber" except that he was probably a Spaniard and wrote about 1300. He was the first to describe sulfuric acid, the most important single substance used by the chemical industries of today (after water, air, coal, and oil). He also described the formation of strong nitric acid. These acids were obtained from minerals, while the earlier known acids, such as the acetic acid of vinegar, came from the world of life.
This discovery of the strong mineral acids was the most important chemical advance after that of the successful production of iron from its ore some three thousand years before. Many chemical reactions could be carried through, and many substances dissolved, by Europeans with the aid of the strong mineral acids, which the earlier Greeks and Arabs could not have brought about with vinegar, the strongest acid at their disposal.
The mineral acids were far more important to the welfare of mankind, in fact, than gold would have been even if that metal could have been produced by transmutation. Gold's value would have disappeared as soon as it was no longer rare, whereas the mineral acids are the more valuable the cheaper and more plentiful they become. Nevertheless, such is human nature that the mineral acids made no great impression, while gold continued to be sought for avidly.
But then, after a promising beginning, alchemy began to degenerate for the third time, as it had done first among the Greeks and then among the Arabs. The hunt for gold became the almost exclusive province of fakers, though great scholars even as late as the seventeenth century (Boyle and Newton are examples) could not resist trying their hand at it.
Once again, as under Diocletian a thousand years before, the study of alchemy was forbidden, as much in dread of the successful production of gold as in indignation over fakery. Pope John XXII declared such a ban in 1317, and honest alchemists, forced to work underground, became more obscure then ever, while chemical racketeering flourished as always.
The winds of change, however, were stirring more and more violently in Europe. The remnant of the Eastern Roman Empire ("Byzantine Empire"), with its capital at Constantinople, was clearly in its last days. In 1204 it had been sacked brutally by western European Crusaders, and much of the record of Greek learning which, till then, had remained intact in that one city at least, was lost forever.
The Greeks recovered the city in 1261, but it was only a shadow of itself thereafter. Over the next two centuries Turkish armies of conquest drew inexorably closer to the city, and finally, in 1453, Constantinople fell and has remained Turkish ever since. Both before and after the fall, Greek scholars fled to western Europe, carrying with them such portions of their libraries as they could salvage. Only feeble remnants of Greek learning were made available to the West, but even they were immensely stimulating.
This was also the age of great explorations, helped on by the discovery, in the thirteenth century, of the magnetic compass. The coast of Africa was explored and the continent was rounded in 1497. With India reached by sea and the world of Islam bypassed, Europe could trade directly with the Far East. Even more startling were the voyages of Christopher Columbus from 1492 to 1504 through which, it was soon discovered (though Columbus himself never admitted the fact), a new half of the world had been revealed.
So much unknown to the great Greek philosophers was being discovered by Europeans that the feeling must arise that the Greeks were not all-knowing supermen after all. The Europeans, having proved superior in navigation, might well prove superior in other respects as well. A certain psychological block was removed, and it became easier to question the findings of the ancients.
In this same "Age of Exploration" a German inventer, Johann Gutenberg (c.1397-c.1468) had devised the first practical printing press, make use of movable type that could be disassembled and put together to print any desired book. For the first time in history, it became possible to produce books cheaply and in quantity, without fear of errors in copying (though, of course, there might be errors in typesetting).
Unpopular views, thanks to printing, need not necessarily die out for lack of anyone to undertake the laborious effort of copying such a book. Thus, one of the early books to appear in printed form was Lucretius's poem and it spread the atomist view far and wide through Europe.
In the year 1543, two revolutionary books were published which, before the days of printing, might easily have been ignored by orthodox thinkers. Now, however, they make their way everywhere and could not be overlooked. One was a book by a Polish astronomer, Nicholas Copernicus (1473-1543), which held that the Earth was not the center of the universe as the great Greek astronomers had maintained, but that the Sun was. The other was a book by a Flemish anatomist, Andreas Vesalius (1514-64), which portrayed human anatomy with unprecedented accuracy. It was based on Vesalius's own observations, and refuted many of the beliefs that dated back to ancient Greek sources.
This simultaneous overthrowing of Greek astronomy and biology (though Greek views maintained their hold in some quarters for a century and more longer) marked the beginning of the "Scientific Revolution". This revolution penetrated the alchemical world only slowly, but it made itself somewhat felt in both the mineralogical and medical aspects of the science.
The End of Alchemy
The new spirit appeared in the works of two contemporaries, both physicians, a German, Georg Bauer (1494-1555) and a Swiss, Theophrastus Bombastus von Hohenheim (1493-1541).
Bauer is better known as Agricola which, in Latin, means "farmer" (as Bauer does, in German). He became interested in mineralogy through its possible connection with medicines. In fact, the connection between medicine and minerals, and the combination of physician-mineralogist, was to be a prominent feature in the development of chemistry for the next two and a half centuries. Agricola's book De Re Metallica ("Of Metallurgy") was published in 1556, and in it he summarized all the practical knowledge that could be gathered from the miners of his day.
This book, clearly written and with excellent illustrations of mining machinery, became popular at once and indeed remains a worthy classic of science even today. (The only English translation of Agricola's work, published in 1912, was made by former President Herbert Hoover, a mining engineer by profession, and his wife.) The most important work on chemical technology before 1700, De Re Metallica established mineralogy as a science. (The most valuable book on metallurgy and applied chemistry generally, prior to Agricola, had been that of a monk Theophilus - possibly a Greek - who lived about A.D. 1000).
As for Von Hohenheim, he is better known by his self-chosen nickname of Paracelsus. This means "better than Celsus," Celsus having been a Roman writer on medical matters whose works had appeared recently in a printed edition. They were the object of much and, to Paracelsus, mistaken idolatry.
Paracelsus, like Avicenna five centuries earlier, represented a shift in alchemical interest from gold to medicine. The purpose of alchemy, Paracelsus maintained, was not to discover techniques for transmutation but to prepare medicines with which to treat disease. In earlier times plant preparations had been most often used for the purpose, but Paracelsus believed heartily in the efficacy of minerals as medicines.
Paracelsus was an alchemist of the old school despite his de-emphasis of transmutation. He accepted the four elements of the Greeks and the three principles (mercury, sulfur, and salt) of the Arabs. He sought unceasingly for the philosopher's stone in its function as the elixir of life, and even insisted he had found it. He also, in greater truth, discovered the metal zinc, and is sometimes considered its discoverer, although zinc, in the form of its ore and in alloy form with copper (brass), was known even in ancient times.
Paracelsus remained a figure of controversy for half a century after his death. His followers increased the content of mysticism in his views and reduced it to a mumbo-jumbo in some respects. This corruption met with disfavor in an era when alchemy was emerging more and more into an era of clarity and rationality.
For instance, the German alchemist Andreas Libau (c.1540-1616), better known by the Latinized name Libavius, published Alchemia in 1597. This work was a summary of the medieval achievements of alchemy and might be considered the first chemical textbook worthy of the name, for he wrote clearly and without mysticism. In fact, he bitterly attached the obscure theories of what he called the "Paracelsians", though he agreed with Paracelsus that the chief function of alchemy was to serve as handmaiden to medicine.
Libavius was the first to describe the preparation of hydrochloric acid, of tin tetrachloride, and of ammonium sulfate. He described also the preparation of aqua regia ("royal water"), a mixture of nitric acid and hydrochloric acid which receives its name from the fact that it can dissolve gold. He even suggested that mineral substances could be identified from the shape of the crystals produced when a solution is evaporated.
Nevertheless, he was certain that transmutation was possible and that the discovery of methods for making gold was an important end of chemical study.
A more specialized textbook was produced in 1604 by a German publisher named Johann Tholde (concerning whom nothing is otherwise known). He ascribed the book to a medieval monk named Basil Valentine, but it seems almost certain that the name was a pseudonym for himself. The book, entitled The Triumphal Chariot of Antimony, dealt with the medicinal uses of this metal and the compounds derived from it.
Still later came a German chemist, Johann Rudolf Glauber (1604-1668), who discovered a method of forming hydrochloric acid by the action of sulfuric acid on ordinary salt. In the process he obtained a residue, sodium sulfate, which we still call "Glauber's salt" even today.
Glauber fastened onto this substance, studying it intensively, and noting its activity as a laxative. He called it "sal mirabile" ("wonderful salt"), and touted it as a cure-all, almost an elixir of life. Glauber went into the business of manufacturing this compound, as well as others which he considered of medical value. He made a successful living out of it, too. It was a less dramatic way of life than that of pursuing the manufacture of gold, but it was more useful and more profitable.
Even to those impervious to scientific rationale, the economic facts of life spoke loudly. There was too much that was useful and profitable in advancing knowledge of minerals and medicine to waste time in the interminable foolish dance after gold.
In the course of the seventeenth century, in fact, alchemy dwindled steadily in importance and in the eighteenth century became what we would today call chemistry.