A genius who took the alchemy out of chemistry

ROBERT BOYLE (1627-1691), the “Father of Chemistry”, was the most influential scientist born in Ireland. His impact on chemistry has been likened to that of Copernicus (1473-1543) on cosmology. Apart from chemistry, Boyle made many other contributions to science.

Robert Boyle was born in Lismore, Co Waterford, the youngest son of Richard Boyle, First Earl of Cork, and his second wife Katherine Fenton. Robert was both scholarly and his father’s favourite son.

After early education at home, Robert went to Eton College. Then, aged 11, he was sent with a tutor on a grand tour of Europe for six years. Apart from his conventional studies on the tour, Robert was also exposed to some vulgar ways of the world. For example, he attracted the amorous attentions of a couple of friars, but he staunchly resisted their “preposterous courtship”.

During his European tour, the young Boyle experienced an awesome thunderstorm which had the effect of a religious conversion experience. Boyle thought he was going to die and felt ill-prepared to meet his Maker. Surviving the storm, he resolved to keep his spiritual side well-serviced so he would not be caught again unawares.

Boyle returned to England in 1644 and embarked on a writing career, initially of pious material. In 1649 he set up a laboratory and began to write accounts of his scientific work, promulgating the use of experiment and the scientific method.

In 1655 Boyle moved to Oxford, where he joined a group of natural philosophers, foreshadowing the Royal Society which was founded in 1660. He employed Robert Hooke (1635-1703) to help him with his experiments. They built the air-pump used to create vacuums and with which Boyle carried out many trials to elucidate the nature and importance of air.

Boyle demonstrated the necessity of air for combustion, for animal breathing, and for the transmission of sound. Prior to moving to London in 1688, he published much influential work, including New Experiments Physio-Mechanical, To uching the Spring of the Air and its Effects(1660) and The Sceptical Chymist(1661). In The Spring of The Air, he described the inverse relationship between the volume of a gas and its pressure, now known as Boyle's Law.

Medieval science was dominated by the ideas of Aristotle (384-322 BC). Aristotle proposed that matter is composed of four elements – earth, air, fire, and water – which, in varying proportions, constitute all things. Paracelsus (1493-1531), an adept in alchemy, proposed that various combinations of three controlling elements (mercury, sulphur, salt) account for the various properties of matter.

Modern chemistry developed out of medieval alchemy. Alchemy was a pseudo-science that sought a method (by varying the proportions of the three controlling elements) of changing base metals into gold, an elixir to prolong life indefinitely, a panacea to cure all ills, and a solvent capable of dissolving anything. Alchemy was still practised in Boyle’s time and he studied the art. Although quite prepared to believe that “cosmical qualities” transcended pure mechanical laws in the universe, he sharply differentiated his scientific experimentation and theorising from his alchemical work.

Francis Bacon (1561-1626) laid down guidelines for the pursuit of inductive science by controlled experiment. But Boyle, the experimenter par excellence, worked out this idea in full and must be credited for properly introducing the modern experimental method into science and for teasing chemistry away from its alchemical origins.

Boyle was very religious and was hostile to views of nature that he saw as detracting from an appreciation of God's power in his creation. His principal target in this respect was the prevailing Aristotelian world-view and he used his experiments to demonstrate that mechanical explanations of the world are better than the qualitative explanations associated with the ideas of Aristotle. In his book, The Sceptical Chymist, Boyle attacked Aristotle's and Paracelsus's theories. He proposed that elements are composed of "corpuscles" of various sorts and sizes capable of organising themselves into groups and that each group constitutes a chemical substance.

He clearly distinguished between mixtures and compounds and showed that a compound can have very different properties from those of its constituents. This prefigured the atomic theory of matter. Boyle declared that the proper object of chemistry was analysis of composition and, indeed, he coined the term analysis itself.

Robert Boyle was friendly with Isaac Newton (1642-1727). Newton worked intensively on alchemical investigations, but he kept this work secret.

In his will, Boyle endowed a series of Boyle Lectures, which still continue, "for proving the Christian Religion against notorious Infidels". His last work, Free Discourse Against Swearing, published posthumously, was dedicated to his brother, the Second Earl of Cork.

William Reville is associate professor of biochemistry and public awareness of science officer at University College Cork - http://understandingscience.ucc.ie