The
UNEXPLAINED

Mysteries of Mind Space and Time

The moment at which the First Matter distils over into the receiving flask is caught wonderfully in this painting by the 18th century artist Joseph Wright of Derby

TWO DAYS AFTER CHRISTMAS in 1666, an unprepossessing stranger visited Johann Friedrich Schweitzer, physician to the Prince of Orange. He was of a mean stature, a little long face, with a few small pock holes, and most black hair, not at all curled, a beardless chin, about three or four and forty years of age (as I guessed), and born in North Holland.

It is clear that Schweitzer - the author of one or two books on medical and botanical matters - was a careful and objective observer.

Above: carrying out their investigations blindly, with little understanding of scientific method or the design of experiments, the alchemists nevertheless laid the basis of modern chemical research. Although the alchemical laboratory frequently looked more like a blacksmith's forge, as in this satirical woodcut, the more sophisticated apparatus changed hardly at all in a thousand years

After some idle conversation, the stranger asked Schweitzer whether he would recognise the 'Philosopher's Stone' if he saw it. This was an astounding question. The Philosopher's Stone was the goal of the alchemists - a fabled substance that could transmute metals into gold, banish all illness and bestow long and vigorous life.

The visitor produced from his pocket a small ivory box that held 'three ponderous pieces or small lumps . . . each about the bigness of a small walnut, transparent, of a pale brimstone colour'. This, he said, was the substance that men had sought so long. Schweitzer took one of the pieces greedily, and begged the man to give him just a small piece. When he was refused, he contrived to scrape a speck beneath his fingernail.

Johann Friedrich Schweitzer, known frequently by the Latinised form of his name, Helvetius was one of the many scientists who believed they had seen the production of gold from base metals

When the visitor had left, promising to return in three weeks and show him 'some curious arts in the fire', Schweitzer hurried to his laboratory for a crucible. He melted some lead in it, and then added the tiny piece of stone. But the metal did not change into gold: 'Almost the whole mass of lead flew away, and the remainder turned into a mere glassy earth.'

Impatiently, the physician awaited the return of the stranger, half believing that he would not come again; but in exactly three weeks his mysterious visitor was once more at the door. For a long time the stranger refused to let Schweitzer take another look at the marvellous stone, but at last 'he gave me a crumb as big as a rape or turnip seed, saying, receive this small parcel of the greatest treasure of the world, which truly few kings or princes have ever known or seen.

Most ungratefully, Schweitzer protested that this was not sufficient to transmute as much as four grains of lead into gold; whereupon the stranger took it back, cut it in half and flung one part in the fire, exclaiming: 'It is yet sufficient for thee!'

Schweitzer then confessed his former theft, and described his lack of success. The stranger laughed and said:

Thou art more dextrous to commit theft than to apply thy medicine; for if thou hadst only wrapped up thy stolen prey in yellow wax, to preserve it from the arising fumes of lead, it would have penetrated to the bottom of the lead, and transmuted it to gold.

He promised to return at nine the next morning and show Schweitzer the correct method.

But the next day he came not, nor ever since. Only he sent an excuse at half an hour past nine that morning, by reason of his great business, and promised to come at three in the afternoon, but never came, nor have I heard of him since; whereupon I began to doubt of the whole matter. Nevertheless late that night my wife . . . came soliciting and vexing me to make experiment saying to me, unless this be done, I shall have no rest nor sleep all this night. . . She being so earnest, I commanded a fire to be made - thinking, alas, now is this man (though so divine in discourse) found guilty of falsehood. . . . My wife wrapped the said matter in wax, and I cut half an ounce or six drams of old lead, and put [it] into a crucible in the fire, which being melted, my wife put in the said Medicine made up in a small pill or button, which presently made such a hissing and bubbling in its perfect operation, that within a quarter of an hour all the mass of lead was transmuted into the . . . finest gold . [Or maybe it was hardened yellow wax? LB]

Right: a chemical laboratory of the 17th century, that of Rudolf Glauber. The furnace, A, contains a flask, B. Above the flask a 'pelican', D - a crude distillation device -delivers vapour into a series of vessels known as 'udels', F

The philosopher Spinoza, who lived not far away, came the next day to examine the gold, and was convinced that Schweitzer was telling the truth. The Assay Master of the province, a certain Mr Porelius, tested the metal and pronounced it genuine; and Mr Buectel, the silversmith, subjected it to further tests that confirmed that it was gold.

There is nothing in Schweitzer's account itself to inspire doubt; he was a reputable medical man and a trained scientific observer, and not given to fraud or practical jokes. And yet, knowing what we do now about the nature of matter, and in particular about the properties of metals, it is impossible to believe that such a transmutation could have taken place.

Schweitzer was certainly not the only scientist, however, to be convinced by practical demonstration that the Philosopher's Stone truly existed, and that it would effect the transmutation of base metals into gold. Another was Jan Baptista van Helmont, a respected chemical experimenter. He had been responsible for a number of important discovenes and was the first man to realise that there were other gases than air; indeed, the word 'gas' was his invention. He had wntten, some 20 years before Schweitzer's meeting with the mysterious stranger:

For truly I have divers times seen it [the Philosopher's Stone] and handled it with my hands, but it was of colour, such as is in Saffron in its powder, yet weighty, and shining like unto powdered glass. There was once given unto me one fourth part of one grain [16 milligrams]. . . . I projected [it] upon eight ounces [227 grams] of quicksilver [mercury] made hot in a crucible; and straightaway all the quicksilver, with a certain degree of noise, stood still from flowing, and being congealed, settled like unto a yellow lump; but after pouring it out, the bellows blowing, there were found eight ounces and a little less than eleven grains of the purest gold.

Right: an Egyptian wall painting of 1300 BC shows goldsmiths (at the left of the two rows of figures), together with joiners. The smiths could make cheap alloys resembling gold and may have possessed the art of electroplating

A fatal blow?

Van Helmont was so impressed with this result that he christened his son Mercurius. Another 17th-century scientist, Rudolf Glauber, the German physician and chemist, believed that he had found one of the ingredients of the Philosopher's Stone in the waters of a spa where he had gone to take a cure. What he found was in fact sodium sulphate, which to this day we know as Glauber's salt - an effective laxative, but not capable of producing gold. No less a thinker than Sir Isaac Newton remained convinced of the possibility of transmutation; so did Descartes, the great French philosopher; and Leibnitz, the great philosopher and mathematician. Even Robert Boyle, whose book, The sceptical chemist, is generally believed to have struck a fatal blow to any serious belief in alchemy, remained certain to the end of his days that transmutation was possible.

Why were all these scientists convinced that it was possible to change metals into gold? The concept is a very ancient one, which seems to answer to deep human motivations. It came to medieval Europe by way of the Arabs. When they invaded Egypt, which they called Khem, in the seventh century, the Arabs discovered that the Egyptians were masters of the art of working in gold. They called gold-working al-kimiya   - 'the art of the land of Khem' - and so, according to one account, the word 'alchemy' was born.

Good as gold

Mankind recognised very early that gold, being virtually indestructible, non-rusting, yet highly malleable, was an ideal medium of exchange. The economy of the major powers is still based on it. Gold almost always appears in the metallic state, commonly in seams or nuggets. Alluvial gold is found deposited in the beds of rivers that have been carrying gold-bearing rocks away for millions of years. Pyrites, or 'fool's gold', is often found close by.

The assaying, or testing, of gold has always been a matter of high importance. Gold jewellery, which must not be damaged, can be weighed and its volume can be measured in order to determine its density: alloys are generally less dense than gold of high purity. In addition, the metal is 'touched' to a touchstone, such as a piece of black jasper, a variety of quartz. The colour of the mark made by gold is different from that made by gilt, brass or copper alloys.

If a piece of gold-bearing ore is to be assayed, the gold is first extracted. The ground ore is heated in a fireclay crucible with lead oxide and charcoal; molten lead settles at the bottom of the crucible as an alloy with any gold and silver present in the ore. The other mineral contents form a floating liquid slag.
The lead 'button' is then heated gently in a small 'cupel', a vessel made of bone ash. The lead turns back into lead oxide, which is absorbed into the cupel, leaving a bead of gold and silver -together, perhaps, with a small amount of platinum. The silver is 'parted' from the gold by being dissolved in hot dilute nitric acid.
Medieval alchemists discovered that gold would not dissolve in nitric, sulphuric or hydrochloric acids - but that it would dissolve in aqua regia, a mixture of nitric and hydrochloric acids. This led to serious misapprehension, since it was often assumed that anything that dissolved in aqua regia (and a great many substances will do so) was thus proved to be gold.

In the great library of Alexandria the Arabs discovered all the writings of the Greek philosophers - in particular those of Aristotle, who lived in the fourth century BC and who can truly be called the first great scientist. The Arabs had the manuscripts copied and translated into Arabic and they found their way all over the Arab world.

Right: Aristotle's scheme of the four elements. Each possesses the two neighbouring 'qualities'. The earth, water, air and fire with which we are familiar are more or less impure approximations to these ideal substances

Aristotle believed that the material world was made from 'prime matter', which in itself lacked all physical properties, but on which different 'forms' could be impressed. Form was not merely physical shape, but every specific property of a body or a substance. Among these were four 'qualities':

wetness, dryness, heat and cold. These qualities gave rise to four 'elements', or simple substances: fire, which was hot and dry; air (for example, steam) which was hot and wet; water, which was cold and wet; earth, which was cold and dry.

From this scheme of things it was very easy to progress to the idea that every substance was composed of all four elements in various proportions. For instance, consider a piece of green wood heated over a fire. First, water appears in droplets at the end of the wood; then steam and vapour are given off; then the wood burns, apparently releasing fire; and finally ash, or earth, is left. To change one substance into another, therefore, it was only necessary to change the proportions of elements in them by addition or subtraction.

Above: the scientist Jan Baptista van Helmont added his voice in support of the reality of transmutation

Below: the Arab alchemist Jabir, in a fanciful European representation of the 17th century

Advances in alchemy

Faced with the impressive skills of the Egyptian metal workers, who knew how to colour cheaper metals to make them look like gold, the Arabs naturally supposed that their secret lay in the application of Aristotle's theories. For hundreds of years Arab scientists experimented in their laboratories. They made many important chemical discoveries and they invented most of the apparatus that is still used by chemists today. But they did not discover how to turn base metal into gold. However, one of the earliest Arab philosophers, Jabir ibn Hayyan, made an important contribution to the development of alchemical theory.

Aristotle had regarded the smoke produced in burning as earthy, and contrasted it with the watery vapour produced when water boils. Stones and minerals that were unchanged by the fire supposedly consisted mainly of this earthy smoke, while metals, which became liquid, were formed from the watery vapour.

Jabir suggested that the vapour produced by boiling water was an intermediate stage in its transformation into air. The vapour could be transformed into a material he called mercury, though this was not the familiar metal, but an ideal substance combining the qualities of lustre and liquidity. Earthy smoke was likewise earth in the process of becoming air, and it could be turned into 'sulphur'. which combined the qualities of earthiness and combustibility. The various metals and minerals were formed in the earth from combinations of mercury and sulphur.

Right: how Jabir ibn Hayyan modified the theory of Aristotle. Like the original four elements, his 'mercury' and 'sulphur' are idealised substances. They combine, respectively, the qualities of lustre and liquidity, and earthiness and combustibility

Jabir investigated what happened when he distilled a wide variety of organic materials - that is, substances derived from living things. In every case he obtained a liquid, which he identified as the element water since it was cold and wet; an 'oil', which, being hot and wet, must be air; a coloured substance - a tincture - that burned, which he thought to be the element fire; and a dry black residue, which he identified as the element earth. He had thus, he believed, isolated the four elements of Aristotle.

He then set out to purify these elements and isolate each quality. By distilling water 700 times, he wrote, he had obtained a brilliant white substance, which crystallised like salt. This, he said, was the purified quality of coldness. He supposed that he would be able to prepare pure moistness from his 'oil'. pure dryness from his 'earth', and pure heat from his 'tincture'. He described the last as a transparent substance, brilliant, lustrous and red. This was the substance that the European alchemists named the Philosopher's Stone.

Below: title page from the 1603 edition of the works of Paracelsus. The author himself is portrayed at the head of the page, and the figure on the right is a representation of Hermes Trismegistos, whose principle 'as above, so below' was the basis of all medieval magical experimentation

The philosophy of the Greeks returned to Europe. together with all the additions made by the Arabs, when Moslem rule was ended in Toledo, in central Spain, towards the end of the 11th century, and Christian scholars were able to translate the Arabic manuscripts in the library there. Soon after, many Europeans began to experiment with alchemy: they included Albrecht, a churchman and philosopher who became known as 'Albertus Magnus' and was renowned for the breadth and profundity of his learning; Roger Bacon, the learned doctor of Oxford University; and Philippus Aureolus Theophrastus Bombastus von Hohenheim.

This arrogant, boastful, colourful character has given his name to all the languages of Europe, for we now describe such a man as 'bombastic'. But he preferred to call himself Paracelsus, implying that he was greater than Celsus, the first-century writer who had been regarded as the greatest authority on medical matters. It was Paracelsus, writing in an extraordinary mixture of Latin, German and invented words, who took the Arabic word for black eye-paint, al-kohl, and gave it to spirits of wine, which has borne the name 'alcohol' ever since. From the German allGeist he made up the word 'alkahest', denoting a supposed universal solvent that would convert all bodies into their prime matter. And from Jabir's theory of elemental sulphur and mercury he developed an alchemical principle that seems to reveal some kind of intuitive understanding of 20th-century physics (see page 1014). His influence was to be a crucial stimulus to the slow development of modern chemistry. But the pursuit of the Philosopher's Stone and the Elixir of Life was still very far from over.

Did some alchemists win the secret of eternal life? See page 954

Metro Feb9,2007

Reproduced from THE UNEXPLAINED p921