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Robert Boyle

1627–1691

 

Ireland is not always thought of as the cradle of scientists, perhaps because science at its purest has little in the way of national character.  However, Robert Boyle is a figure which any country would be proud of.  'Boyle's Law', as we are taught at school, is a key scientific fact.  He was interesting as both a philosopher and a physicist and chemist.  His contemporaries were aware of his curious position, as a friendly Irish epitaph described him as the 'Father of Chemistry and the Uncle of the Earl of Cork'.

      He was born on 25th January 1627, at Lismore Castle in County Waterford, in the south of Ireland, the seventh son of the famous first earl of Cork, an important figure in the plantation of Munster.  He was a serious child with a taste for study which impressed his father.  He was sent to Eton College at the age of eight, and there (according to a fragment of autobiography that he left unpublished) a chance reading of Quintus Curtius 'conjured up in me that unsatisfied appetite for knowledge that is yet as greedy as when it was first raised'.

      After four years study at Eton he returned home to be taught by tutors, and was then sent around Europe with his French tutor, becoming fluent in French and Italian, then the languages of culture.  In Florence in the winter of 1641 to 1642 he came into contact with the new ideas of Galileo.  These travels were made difficult because the money sent by his father was stolen, and the party had to return to England slowly by a roundabout route.  In 1644 he returned to live in Dorset, in the south of England, on an estate he had inherited from his father.

      Boyle was one of what was called 'the invisible college' of scientists and philosophers, which was to become the Royal Society, and though he was still in his late teens he acquired an impulse toward investigation that lasted his lifetime.  He visited Ireland in 1652 to deal with his estates, but found it 'a barbarous country, where chemical spirits were so misunderstood, and chemical instruments unprocurable, that it was hard to have any Hermetic thoughts in it'.  Instead, he turned to anatomy, Ireland having a ready supply of dead bodies in those days.  On returning to England in 1654 he settled in Oxford, where he lived until moving finally to London in 1668 to be nearer the centre of things in the capital.

      He erected a laboratory where he and his assistants worked, and created a small scientific society around him.  In 1659 he invented, with the help of Robert Hooke, the 'machina Boyleana', the first air pump, which he used in experiments that led up to the propounding of Boyle's Law.

      His first experiments with the properties of air were published in 1660.  In 1661 he published what came to be seen as his magnum opus, The Skeptical Chymist ... Touching the Experiments Whereby Vulgar Spagirists Are Wont to Endeavour to Evince Their Salt, Sulphur, and Mercy to the True Principles of Things.  In this work he overthrew the Aristotelian concept of the four elements of earth, fire, water, and air.  In proposing the modern idea of an element as a substance which cannot be decomposed into simpler ones, he had grasped the idea on which all modern chemistry was later founded.

      His interests covered many areas, including the possibility of transmuting base metals into gold.  But he is remembered for proving that air is a material substance, having weight, its volume being inversely proportional to its pressure.  This relationship is Boyle's Law, which he defined and which Edme Mariotte later proved.  This is still among the first basic facts of science that all students learn at school.

      He also made observations on the effect of a change in atmospheric pressure on the boiling point of water, collected many new facts in relation to magnetism and electricity, and explained the action of heat as a 'brisk' agitation of particles.

      But it was as a chemist that Boyle excelled.  He was not a theorist, but an experimenter, and as such, the first modern chemist.  He distinguished elements, mixtures, and compounds, prepared phosphorus (though he did not discover it), collected hydrogen in a vessel over water (though he called it 'air generated de novo') and inquired into the forms of crystals as an indicator of their chemical structures.  He introduced the vegetable colour tests for acidity and alkalinity, the construction of hermetically sealed thermometers, and the use of freezing mixtures.

      He was also a deeply devout Christian, and learned Hebrew, Syrian, and Greek, the better to understand the scriptures.  He used a large part of his personal fortune in the propagation of the faith, and in his will left a sum of money to support the annual Boyle Lectures, eight sermons a year by a minister 'for proving the Christian religion against Atheists, Theists, Pagans, Jews, and Mohammedans, not descending to any controversies among Christians themselves'.

      As a philosopher he thought that God had made the world in the beginning and that His 'general concourse' was continually needed to maintain its being and motion.  This was a return in part to earlier Hindu and Islamic ideas of continuous creation and recreation, but also expressed the physical aspect of the Christian doctrine of immanence.

      Boyle died in London on 31st December 1691.  He was thought by all to be a man of fine character, and was very popular among his colleagues.  His reputation was an international one, and he was always at the service of visitors to the Royal Society.  But his fame will rest on his invention of 'the experimental method' by which all scientific research now proceeds.