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ALCHEMY

photo of an ancient document showing some of the symbols commonly used by alchemists

Alchemical symbols

Understanding of the alchemists is hampered by their predilection for making their writings incomprehensible ( instant knowledge was not to be available to the uninitiated ) and the popular view that their quest was simply to isolate the Philosophers’ Stone and to use it to transform base metals into gold.
There was in fact a genuine search for mental and spiritual advance.

Using a world-view totally unlike that recognised today, the alchemists’ ideas of ‘spirit’ and ‘matter’ were intermingled – the ability to use ‘spirit’ in their experiments was the difficult part.
alchemical symbol for gold
To transform copper to gold: – copper could be heated with sulphur to reduce it to its ‘basic form’ (a black mass which is in fact copper sulphide) – its ‘metallic form’ being ousted by the treatment. The idea of introducing the ‘form of gold’ to this mass by manipulating and mixing suitable quantities of spirit stymied alchemists for over fifteen centuries.

Whilst this transmutation of metals was the mainstream concern of alchemy, there emerged in the sixteenth century a school that brought the techniques and philosophies of alchemy to bear on the preparation of medicines, two of the main figures involved being PARACELSUS and JOHANN VAN HELMONT

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THE EIGHTEENTH CENTURY

COMBUSTION and PHLOGISTON

 

Noticing that burning a candle in an upturned container, the open end of which is submerged in water, causes the water to rise into the container, Philon of Byzantium inferred correctly that some of the air in the container had been used up in the combustion. However, he proposed that this is because this portion of the air had been converted into ‘fire particles’, which were smaller than ‘air particles’.

In 1700 the German physician Georg Ernst Stahl (1660-1734) invoked ‘phlogiston’ to explain what happens when things burn. He suggested that a burning substance was losing an undetectable elementary principle, analogous to the ‘sulfur’ of J’BIR IHBIN AYAM, which he re-named ‘phlogiston’. This could explain why a log (rich in phlogiston) could seem to be heavier than its ashes (deficient in phlogiston). The air that is required for burning served to transport the phlogiston away.

The English chemist JOSEPH PRIESTLY (1733-1804), although a supporter of the phlogiston theory, ironically contributed to its downfall. He heated mercury in air to form red mercuric oxide and then applied concentrated heat to the oxide and noticed that it decomposed again to form mercury whilst giving off a strange gas in which things burnt brightly and vigorously. He concluded that this gas must be ‘phlogiston poor’.

Priestly combined this result with the work of the Scottish physician Daniel Rutherford (1749-1819), who had found that keeping a mouse in an enclosed airtight space resulted in its death (by suffocation) and that nothing could be burnt in the enclosed atmosphere; he formed the idea that the trapped air was so rich in phlogiston that it could accept no more. Rutherford regarded this as ‘phlogisticated air’ and so Priestly called his own gas ‘dephlogisticated air’.

In 1774 Priestley visited the French chemist ANTOINE LAVOISIER (1743-1794).
Using chemical reactions, Lavoisier had combined a portion of normal air with other substances.
Lavoisier repeated Priestly’s experiments with careful measurements.
Reasoning that air is made up of a combination of two gases – one that will support combustion and life, another that will not; what was important about Lavoisier’s experiments was not the observation – others had reached a similar conclusion – but the interpretation.

Lavoisier called Priestley’s ‘dephlogisticated air’, ‘oxygene’, meaning ‘acidifying principle’, believing at the time that the active principle was present in all acids (it is not). Classifying oxygen as an element, he called the remaining portion of normal air ‘phlogisticated air’, ‘azote’, meaning ‘without life’.

Oxygen is the mirror image of phlogiston. In burning and rusting (the two processes being essentially the same) a substance picks up one of the gases from the air. Oxygen is consumed, there is no expulsion of ‘phlogiston’.

Lavoisier had been left with almost pure nitrogen, which makes up about four fifths of the air we breath. We now know azote as nitrogen. Rutherford’s ‘mephitic air’ was carbon dioxide.

CALORIC

Like phlogiston, caloric was a weightless fluid, rather like elemental fire; a quality that could be transmitted from one substance to another, so that the first warmed the second up.

It was believed that all substances contained caloric and that when a kettle was being heated over a fire, the fuel gave up its caloric to the flame, which passed it into the metal, which passed it on to the water. Similarly, two pieces of wood rubbed together would give heat because abrasion was releasing caloric trapped within.

What is being transmitted is heat energy. It was the crucial distinction between the physical and the chemical nature of substances that confused the Ancients and led to their minimal elemental schemes.

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CHRISTIAN THEOLOGY & WESTERN SCIENCE

bust said to depict a likeness of Socrates

The speculative Greek philosophers, considering the great overarching principles that controlled the Cosmos, were handicapped by a reluctance to test their speculations by experimentation.
At the other end of the spectrum were the craftsmen who fired and glazed pottery, who forged weapons out of bronze and iron. They in turn were hindered by their reluctance to speculate about the principles that governed their craft.

WESTERN SCIENCE is often credited with discoveries and inventions that have been observed in other cultures in earlier centuries.
This can be due to a lack of reliable records, difficulty in discerning fact from legend, problems in pinning down a finding to an individual or group or simple ignorance.

The Romans were technologists and made little contribution to pure science and then from the fall of Rome to the Renaissance science regressed. Through this time, science and technology evolved independently and to a large extent one could have science without technology and technology without science.

Later, there developed a movement to ‘Christianise Platonism’ (Thierry of Chartres).

Platonism at its simplest is the study and debate of the various arguments put forward by the Greek philosopher PLATO (428/7-348/7 BCE).
The philosopher Plotinus is attributed with having founded neo-Platonism, linking Christian and Gnostic beliefs to debate various arguments within their doctrines. One strand of thought linked together three intellectual states of being: the Good (or the One), the Intelligence and the Soul. The neo-Platonic Academy in Greece was closed by the Emperor Justinian (CE 483-565) in CE 529.
During the early years of the Renaissance, texts on neo-platonism began to be reconsidered, translated and discoursed.

Aristotle’s four causes from the ‘Timaeus’ were attributed to the Christian God, who works through secondary causes (such as angels).

Efficient Cause – Creator – God the Father

Formal Cause – Secondary agent – God the Son

Material Cause – The four elements: earth, air, fire & water.
Because these four are only fundamental forms of the single type of matter, they cannot be related to any idea of ‘elements’ as understood by modern science – they could be transmuted into each other. Different substances, although composed of matter would have different properties due to the differing amounts of the qualities of form and spirit. Thus a lump of lead is made of the same type of matter (fundamental form) as a lump of gold, but has a different aggregation of constituents. Neither lead nor gold would contain much spirit – not as much as air, say, and certainly not as much as God, who is purely spiritual. ( ALCHEMY )

Final Cause – Holy Spirit

All other is ‘natural’ – underwritten by God in maintaining the laws of nature without recourse to the supernatural.
Science was the method for investigating the world. It involved carrying out careful experiments, with nature as the ultimate arbiter of which theories were right and which were wrong.

Robert Grosseteste (1168-1253) Bishop of Lincoln (Robert ‘Bighead’) – neo-platonic reading of Genesis – emanation of God’s goodness, like light, begins creation. Light is thus a vehicle of creation and likewise knowledge (hence ‘illumination’), a dimensionless point of matter with a dimensionless point of light superimposed upon it (dimensions are created by God). Spherical radiation of light carries matter with it until it is dissipated. Led to studies of optical phenomena (rainbow, refraction, reflection).

Stained glass window depicting Bishop Robert Grosseteste (created 1896)

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ROGER BACON (1214- 94)

(Doctor Mirabilis) ‘The Marvelous Doctor’

(Franciscan friar) Oxford – 1257

Mathematics (The first of the sciences, the alphabet of philosophy, door & key to the sciences), not Logic, should be the basis of all study

Converted from Aristotelian to a neo-Platonist.

Etching of ROGER BACON Franciscan friar (1214- 94)

ROGER BACON

The Multiplication of Species; the means of causation (change) radiate from one object to another like the propagation of light.

‘An agent directs its effect to making the recipient similar to itself because the recipient is always potentially what the agent is in actuality.’

Thus heat radiating from a fire causes water placed near the fire,
but not in it, to become like the fire (hot). The quality of fire is multiplied in the water (multiplication of species).

All change may be analysed mathematically. Every multiplication is according to line, angles or figures. This thinking comes from the ninth century al-Kinde and his thoughts on rays and leads to a mathematical investigation into light.

Fear of the Mongols, Muslims and the Anti-Christ motivated the Franciscans. Franciscan neo-Platonism was based on Augustinian thought with a mathematical, Pythagorean, approach to nature. Bacon subscribed to this apocalyptical view, suffered trial and was imprisoned.
The Dominicans chose Aristotle – with a qualitative, non-mathematical approach to the world.

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JOHN DEE (1527-1608)

1590 – London, England

Portrait of Dr John Dee (1527-1608/9) John Dee was a much respected scientist in his own time, but subsequently derided as a conjurer and a trickster. He conceived the universe as being based on essentially magical principles, though believed that many of its rules and laws could be approached through mathematics.

JOHN DEE

Mathematician, cartographer & astronomer.
Prolific author, natural magician, alchemist

‘Alternative knowledge and methods of learning. ‘Conversations with Angels’. Human power over the world (neo-Platonism).’

Dee was a Hermetic philosopher, a major influence on the ROSICRUCIANS, possibly a spy – astrologer and adviser to Queen Elizabeth I ; he chose the day of her coronation.

One of the greatest scholars of his day. His library in his home in Mortlake, London, contained more than 3,000 books.

Greatly influenced by Edward Kelley (1555- 97), whom he met in 1582; from 1583-1589 Dee and Kelley sought the patronage of assorted mid-European noblemen and kings, eventually finding it from the Bohemian Count Vilem Rosenberg.

In 1589, Dee left Kelley to his alchemical research and returned to England where Queen Elizabeth I granted him a position as a college warden, but he had lost respect owing to his occult reputation.
Dee returned to Mortlake in 1605 in poor health and increasing poverty and ended his days as a common fortune-teller.

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WILLIAM GILBERT (1540-1603)

1600 – England

Gilbert’s principal area of study related to magnetism, however, his method of enquiry is equally significant

Gilbert rejected the scholastics’ approach to science, preferring the experimental method, which he applied to the Earth’s magnetic properties.
He carried out some of the first systematic studies of the lodestone in Europe and showed that the Earth acts as a bar magnet with magnetic poles.

portrait of WILLIAM GILBERT ©

WILLIAM GILBERT

His celebrated work,’De magnete, magnetisque corporibus, et de magno magnete tellure‘ (On the Magnetic, Magnetic Bodies and the Great Magnet Earth – 1600) is considered to be one of the first truly scientific texts.

Gilbert received his medical training in Cambridge and practiced as a physician in London. He became president of the College of Physicians and was physician to Queen Elizabeth I.

In the time of Elizabeth I and Shakespeare, England was still largely a place of superstition and religious fervor. Gilbert concurred with Copernicus, a potentially dangerous sentiment in an era when elsewhere in Europe others such as Giordano Bruno and later GALILEO were being persecuted (and in the case of Bruno, executed) for sharing the same opinion.


Magnetism was to cast its influence in the eighteenth century, displayed through the animal magnetism and the electric fluid of GALVANI and VOLTA
.

He distinguished the properties of magnetism from the attractive effect produced by friction with amber. In so doing he introduced the term that was to become electricity.
Gilbert introduced a number of expressions to the English language including: magnetic pole, electric force and electric attraction.
A term of magneto-motive force, the gilbert, is named after him.

Gilbert and others postulated that magnetism is the force holding the planets in their orbits.

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JOHANNES KEPLER (1571-1630)TIMELINE

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FRANCIS BACON (1561-1626)

1620 – England

Scientific laws must be based on observations and experiments

Bacon rejected ARISTOTLE‘s deductive or a priori, approach to reasoning and suggested his own, inductive, or a posteriori, approach. Bacon developed the scientific method – but he did not make any significant scientific discovery.

‘I shall content myself to awake better spirits like a bell-ringer, who is first up to call others to church’

Portrait of FRANCIS BACON ©

FRANCIS BACON

Bacon, a philosopher, advocated a new method of enquiry, completely different from the philosophical methods of the ancient Greeks, in his book Novum Organum – which has influenced scientists since its publication in 1620.

The text proposed the sentiment of ‘The Advancement of Learning’ (1605) signaling dissatisfaction with the limits of, and approaches to, knowledge to date and foresaw a future where the ancient masters would be far surpassed – Aristotle had written a text called Organum or ‘Logical Works’ and Bacon’s ‘new’ approach suggested an alternative direction for scientific study.

Bacon strongly criticised Aristotle’s deductive method of science, which involved formulating abstract ideas and ‘logically’ building upon them step-by-step to find ‘truths’, without thorough consideration of whether the theoretical foundation in itself was ever valid.

Rather than rely on superstition or accept unquestioningly the flawed solutions of the ancient academics as had largely been the case for two thousand years, Bacon’s alternative was to argue for ‘inductive’ reason, where the only ‘certain’ statements that should ever be made were based on observation and proof collected from the natural world. The essence of his method is to collect masses of data by observations and experiments, analyse facts by drawing up tables of negative, affirmative and variable instances of the phenomenon ( ‘Tables of Comparative Instances’ ), draw (induce) hypotheses from the evidence, then to collect further evidence to proceed towards a more general theory. The most important aspect of this method was the idea of drawing up tentative hypotheses from available data and then verifying them by further investigations.

‘A true and fruitful natural philosophy has a double scale or ladder ascendant or descendant, ascending from experiments to axioms and descending from axioms to the invention of new experiments’, he wrote in Novum Organum.

Bacon cautioned those trying to practice his new method, urging them to repudiate four kinds of intellectual idol

  • Perceptual Illusions – ‘idols of the tribe’
  • Personal biases – ‘idols of the cave’
  • Linguistic confusions – ‘idols of the market place’
  • Dogmatic philosophical systems – ‘idols of the theatre’

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WILLIAM HARVEY (1578-1657)

1628 – London, England

Circulation of the blood

Portrait of WILLIAM HARVEY ©

WILLIAM HARVEY

As WILLIAM GILBERT had begun in physics, and FRANCIS BACON had subsequently implored, Harvey was the first to take a rational, modern, scientific approach to his observations in biology.
Rather than taking the approach of the philosophers, which placed great emphasis upon thinking about what might be the case, Harvey cast aside prejudices and only ‘induced’ conclusions based on the results of experiments and dissections, which could be repeated identically again and again.

After what GALEN had begun and VESALIUS had challenged, Harvey credibly launched perhaps the most significant theory in his field of biology. He postulated and convincingly proved that blood circulated in the body via the heart – itself little more than a biological pump.

Galen had concluded that blood was made in the liver from food, which acted as a fuel, which the body used up, thereby requiring more food to keep a constant supply. Vesalius added little to this theory. Harvey, physician to Kings James I and later Charles I proved his theory of circulation through rigorous and repeated experimentation. He correctly concluded that blood was not used up, but is recycled around the body.

An illustration depicting William Harvey (April 1, 1578 - June 3, 1657), the medical doctor credited with first describing the properties of the human circulatory system, seeing a patient. ©

His dissections proved that the arteries took blood from the heart to the extremities of the body, able to do so because of the heart’s pump-like action. He could see that the pulses in arteries came immediately after the heart contracted, and became certain that the pulse was due to blood flowing into the vessels.
By careful observation he found that blood entered the right side of the heart and was forced into the lungs, before returning to the left side of the heart. From there it was pumped via the aorta into the arteries around the body.

Harvey realized that the amount of blood flowing around the system was too much for the liver to produce. The blood had to be circulating back to the veins; which, with their series of one-way valves, brought blood back to the heart.
Without a microscope it was impossible to see the minute capillaries that linked the arteries to the veins.

Exercitatio anatomica de motu cordis et sanguinis in animalibus William Harvey (1628)

Harvey published his findings in the 720 page ‘Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus‘ ( Anatomical Exercise on the Motion of The Heart and Blood in Animals ) at the Frankfurt Book Fair in 1628.

Initially supported by some academics, an equal number rejected his ideas. One area of weakness was that he was unable to offer a proven explanation for how the blood moved from the arteries to the veins. He speculated that the exchange took place through vessels too small for the human eye to see, which was confirmed shortly after his death with the discovery of capillaries by Marcello Malphigi with the recently invented microscope.

Even then, nobody knew what blood was doing. It would take another hundred years before ANTOINE LAVOISIER discovered oxygen and worked out what it did in the body.

In 1651, Harvey published ‘Exercitationes de Generatione Animalium‘ ( Essays on the Generation of Animals ), a work in the area of reproduction which included conjecture that rejected the ‘spontaneous generation’ theory of reproduction which had hitherto persisted. His belief that the egg was at the root of life gained acceptance long before the observational proof some two centuries later.

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ROBERT BOYLE (1627- 91)

1662 – England

The volume of a given mass of a gas at constant temperature is inversely proportional to its pressure

If you double the pressure of a gas, you halve its volume. In equation form: pV = constant; or p1V1 = p2V2 where the subscripts 1 & 2 refer to the values of pressure and volume at any two readings during the experiment.

Born at Lismore Castle, Ireland, Boyle was a son of the first Earl of Cork. After four years at Eton College, Boyle took up studies in Geneva in 1638. In 1654 he moved to Oxford where in 1656, with the philosopher John Locke and the architect Christopher Wren, he formed the experimental Philosophy Club and met ROBERT HOOKE, who became his assistant and with whom he began making the discoveries for which he became famous.

Robert Boyle. New Experiments Physico-Mechanical. Oxford: Thomas Robinson, 1662

New Experiments Physico-Mechanical 1662

In 1659, with Hooke, Boyle made an efficient vacuum pump, which he used to experiment on respiration and combustion, and showed that air is necessary for life as well as for burning. They placed a burning candle in a jar and then pumped the air out. The candle died. Glowing coal ceased to give off light, but would start glowing again if air was let in while the coal was still hot. In addition they placed a bell in the jar and again removed the air. Now they could not hear it ringing and so they found that sound cannot travel through a vacuum.

He proved Galileo’s proposal that all matter falls at equal speed in a vacuum.

Boyle established a direct relationship between air pressure and volumes of gas. By using mercury to trap some air in the short end of a ‘J’ shaped test tube, Boyle was able to observe the effect of increased pressure on its volume by adding more mercury. He found that by doubling the mass of mercury (in effect doubling the pressure), the volume of the air in the end halved; if he tripled it, the volume of air reduced to a third.
His law concluded that as long as the mass and temperature of the gas is constant, then the pressure and volume are inversely proportional.

Boyle appealed for chemistry to free itself from its subservience to either medicine or alchemy and is responsible for the establishment of chemistry as a distinct scientific subject. His work promoted an area of thought which influenced the later breakthroughs of ANTOINE LAVOISIER (1743-93) and JOSEPH PRIESTLY (1733-1804) in the development of theories related to chemical elements.

Boyle extended the existing natural philosophy to include chemistry – until this time chemistry had no recognised theories.

The idea that events are component parts of regular and predictable processes precludes the action of magic.
Boyle sought to refute ARISTOTLE and to confirm his atomistic or ‘corpuscular’ theories by experimentation.

In 1661 he published his most famous work, ‘The Skeptical Chymist’, in which he rejected Aristotle’s four elements – earth, water, fire and air – and proposed that an element is a material substance consisting at root of ‘primitive and simple, or perfectly unmingled bodies’, that it can be identified only by experiment and can combine with other elements to form an infinite number of compounds.

The book takes the form of a dialogue between four characters. Boyle represents himself in the form of Carneades, a person who does not fit into any of the existing camps, as he disagrees with alchemists and sees chemists as lazy hobbyists. Another character, Themistius, argues for Aristotle’s four elements; while Philoponus takes the place of the alchemist, Eleutherius stands in as an interested bystander.

In the conclusion he attacks chemists.

“I think I may presume that what I have hitherto Discursed will induce you to think, that Chymists have been much more happy finding Experiments than the Causes of them; or in assigning the Principles by which they may be best explain’d”  page from one of Boyle's publicationsHe pushes the point further- “me thinks the Chymists, in the searches after truth, are not unlike the Navigators of Solomon’s Tarshish Fleet, who brought home Gold and Silver and Ivory, but Apeas and Peacocks too; For so the Writings of several (for I say not, all) of your Hermetick Philosophers present us, together with divers Substantial and noble Experiments, Theories, which either like Peacock’s feathers made a great show, but are neither solid nor useful, or else like Apes, if they have some appearance of being rational, are blemished with some absurdity or other, that when they are Attentively consider’d, makes them appear Ridiculous”

The critical message from the book was that matter consisted of atoms and clusters of atoms. These atoms moved about, and every phenomenon was the result of the collisions of the particles.

He was a founder member of The Royal Society in 1663. Unlike the Accademia del Cimento the Royal Society thrived.

Like FRANCIS BACON he experimented relentlessly, accepting nothing to be true unless he had firm empirical grounds from which to draw his conclusions. He created flame tests in the detection of metals and tests for identifying acidity and alkalinity.

It was his insistence on publishing chemical theories supported by accurate experimental evidence – including details of apparatus and methods used, as well as failed experiments – which had the most impact upon modern chemistry.

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ROBERT HOOKE (1635-1703)

1670 – England

Within the limits of elasticity, the extension ( Strain ) of an elastic material is proportional to the applied stretching force ( Stress )

Hooke’s law applies to all kinds of materials, from rubber balls to steel springs. The law helps define the limits of elasticity of a material.

In equation form; the law is expressed as F = kx, where F is force, x change in length and k is a constant. The constant is known as Young’s Modulus, after THOMAS YOUNG who in 1802 gave physical meaning to k.

Boyle and Hooke formed the nucleus of scientists at Gresham College in Oxford who were to create the Royal Society in 1662 and Hooke served as its secretary until his death. Newton disliked Hooke’s combative style (Hooke accused Newton of plagiarism, sparking a lifelong feud between the two) and refused to attend Royal Society meetings while Hooke was a secretary.

Hooke mistrusted his contemporaries so much that when he discovered his law he published it as a Latin anagram, ceiiinosssttvu, in his book on elasticity.

Two years later, when he was sure that the law could be proved by experiments on springs, he revealed that the anagram meant Ut tensio sic vis. That is, the power of any spring is in the same proportion with the tension thereof.

At the same time, in 1665 Hooke published his work Micrographia presenting fifty-seven illustrations drawn by him of the wonders seen with the microscope.

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EDMUND HALLEY (1656-1742)

1682 – England

Halley’s comet

Despite his many achievements, it is arguable that the most important factor influencing the legacy of Edmund Halley is his friendship with Newton.
He encouraged Newton to undertake the ‘Principia’ in the first place; he went on to edit and proof read the text, write the preface and to finance its publication in 1687.
Had Edmund Halley not been born, his comet would still exist, albeit under a different name. Newton’s Principia, at least in the form the world knows it today, almost certainly would not.

frontispiece of tables produced by EDMUND HALLEY (570 x 400)

Halley was a prolific mapmaker, showing prevailing winds, tides and magnetic variations in his cartography.

Halley’s Comet will return to the skies in 2062.

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