Humphry Davy

• 1. Introduction

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  In 1799, Humphry Davy breathed sixteen quarts of a gas for nearly seven minutes, and it absolutely intoxicated him. He called it laughing gas, and he laughed. He was a chemist working at a medical research facility in Bristol, and he was astonished at the effect. In his notes he wrote that the gas might be useful for performing surgical operations. Davy was born in Penzance, Cornwall, on the 17th of December 1778, the eldest of five children of a woodcarver. He would isolate more chemical elements for the first time than perhaps any person before or since. He would invent a lamp that saved the lives of coal miners. He would also nearly kill himself more than once, gasping in a garden, taking his own racing pulse as he staggered into the open air. How did a surgeon's apprentice from a Cornish town with, by his own brother's account, little taste for science, become President of the Royal Society? And why did a man who wrote over a hundred and sixty poems come to call his own early work the dreams of misemployed genius?

• 2. Tearing Apart Compounds

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  Potassium was the first metal ever isolated by electrolysis, and Davy pulled it out of caustic potash in 1807. He passed electricity through common compounds to split them and prepare new elements that no one had separated before. That same year he isolated sodium by sending an electric current through molten sodium hydroxide. Until then, no distinction had even been made between the two metals.

  During the first half of 1808, Davy turned his voltaic batteries on the alkaline earths, working with lime, magnesia, strontites and barytes. In early June a letter arrived from the Swedish chemist Berzelius, who reported that he and a Dr. Pontin had obtained amalgams of calcium and barium using a mercury cathode. Davy repeated the work almost immediately and pushed the method further. On the 30th of June 1808 he told the Royal Society he had isolated four new metals. He named them barium, calcium, strontium and magnium, the last later changed to magnesium.

  Davy conceded that magnium was, in his own word, an undoubtedly objectionable name. He had reached for it because the more natural choice, magnesium, was already being applied to metallic manganese, and he wished to avoid an equivocal term. The experiments of that year also led him to isolate boron in 1809, a stretch of discovery that turned the study of how electricity drives these separations into a new field of its own.

• 3. The Naming Of Things

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  Chlorine takes its name from the Greek word chloros, meaning green-yellow, chosen by Davy in 1810 for what he called one of the substance's obvious and characteristic properties, its colour. The substance had been discovered back in 1774 by the Swedish chemist Carl Wilhelm Scheele, who called it dephlogisticated marine acid and wrongly believed it contained oxygen. Davy proved that Scheele's substance held no oxygen at all, and in doing so overturned an earlier definition of acids as compounds of oxygen.

  Aluminium became a battleground over a single letter. Davy is credited with naming the element, and his first proposal was alumium, suggested in an 1808 article on his electrochemical research. Chemists in France, Germany and Sweden objected, insisting the metal be named for the oxide, alumina, from which it would come. The form aluminium was put forward by January 1811 by William Hyde Wollaston, writing an account of Davy's experiments. Davy himself later used aluminum, by 1812, which remains the word used in the United States.

  His 1806 lecture on the chemical agencies of electricity drew rare praise. Berzelius called it one of the best memoirs which has ever enriched the theory of chemistry.

• 4. Danger In The Laboratory

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  I do not think I shall die, Davy faintly articulated, after he tried to inhale four quarts of pure hydrocarbonate in a carbon monoxide experiment and seemed sinking into annihilation. He had to be carried into the open air, and hours passed before the painful symptoms ceased. His respiration of nitric oxide, which may have formed nitric acid in his mouth, severely injured the mucous membrane. He ran these risks on himself as a matter of method.

  Nitrogen trichloride nearly took his sight. The French chemist Pierre Louis Dulong had first prepared the compound in 1811 and had lost two fingers and an eye in two separate explosions. In a letter to John Children on the 16th of November 1812, Davy warned that it was not safe to experiment on a globule larger than a pin's head, and admitted he had been severely wounded by a piece scarcely bigger.

  That accident had a lasting consequence. It induced Davy to hire Michael Faraday as a co-worker, particularly to help with handwriting and record keeping. The two were injured together in another explosion shortly afterward. Davy had recovered by April 1813, with an assistant beside him whose name would one day outshine his own.

• 5. Showman And Lecturer

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  Nearly 500 people packed the room for one of Davy's lectures at the Royal Institution, and he wrote to John King in delight: There was Respiration, Nitrous Oxide, and unbounded Applause. Amen. He had given his first lecture, on the new subject of galvanism, on the 25th of April 1801. His talks blended spectacular and sometimes dangerous demonstrations with a vision of human progress, presented by a young and handsome man with a gift for showmanship.

  Davy wove poetry and religious commentary into his lectures, arguing that God's design was revealed by chemical investigation. Part of that was an effort to appeal to the women in his audiences. He supported female education and women's involvement in science, even proposing that women be admitted to evening events at the Royal Society. He acquired a large female following around London. In a satirical Gillray cartoon, nearly half the attendees shown are women, and his support drew gossip and accusations that he was unmanly.

  His rise was swift. By June 1802, after just over a year and at the age of 23, Davy was made full lecturer at the Royal Institution. The incumbent, Garnett, quietly resigned, citing health reasons. The friendship that fed those lectures ran deep; Coleridge said he attended Davy's lectures to enlarge his stock of metaphors.

• 6. The Miners' Lamp

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  Ninety-two men were killed in the Felling mine disaster of 1812 near Newcastle, an explosion of the kind that left widows and children to be supported by the public purse. After returning to England in 1815, Davy began experimenting with lamps that could be used safely in coal mines. The Reverend Dr Robert Gray of Bishopwearmouth, founder of the Society for Preventing Accidents in Coalmines, had urged Davy to apply his chemical knowledge to explosions caused by firedamp, methane mixed with oxygen, often ignited by the open flames of miners' lamps.

  Davy's answer was to enclose the flame in iron gauze, so the methane burning inside could not pass out to ignite the surrounding air. The idea of a safety lamp had already been shown by William Reid Clanny and by the then unknown engineer George Stephenson, whose own lamp was very popular in the north-east coalfields. But Davy's use of wire gauze was taken up by many later inventors. The new lamp had a cruel flaw. It gave much less light and deteriorated in the wet of most pits, and rusting gauze made it unsafe, so deaths from firedamp rose still further.

  Davy refused to patent the lamp. For his invention he was awarded the Rumford medal in 1816. There was some dispute over whether he had reached the principle without the work of Smithson Tennant, but it was generally agreed the two men had worked independently.

• 7. Grand Tour And Strange Errands

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  Davy succeeded in using the sun's rays to ignite a diamond in Florence, proving it is composed of pure carbon, with Faraday assisting and the burning glass of the Grand Duke of Tuscany. In 1812 he had been knighted, given up his lecturing post, and married a wealthy widow, Jane Apreece. In October 1813 he set out for France with his wife and Faraday, who served as scientific assistant and was also treated as a valet, to collect a medal that Napoleon Bonaparte had awarded him for his electro-chemical work. Faraday called it a strange venture, trusting themselves to a foreign and hostile country.

  In Rome, Davy carried out the first chemical research on the pigments used by artists. The party visited the Empress Josephine at the Chateau de Malmaison, met Andre-Marie Ampere in Paris, and in Milan met Alessandro Volta. In Paris he attended lectures by Joseph Louis Gay-Lussac on a substance isolated by Bernard Courtois, now called iodine, which led to a dispute over who held priority on the research.

  Davy returned to the unrolling of charred scrolls. He experimented on fragments of the Herculaneum papyri, finding that chlorine made the layers separate and the letters appear more distinct. He traveled to Naples and partially unrolled 23 manuscripts. But the work soured. After returning to Naples on the 1st of December 1819, he complained the men at the museum were no longer helpful but obstructive, and he renounced the work.

• 8. Decline And A Greater Discovery

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  On the 20th of October 1818, Davy was created a baronet, the first such honour given to a man of science in Britain. A year later came the presidency of the Royal Society, and he was elected on the 30th of November 1820, aged only 41. The Society was shifting from a gentlemen's club into an academy of specialised sciences. His strongest rival had been William Hyde Wollaston, backed by a Cambridge network of mathematicians including Charles Babbage and John Herschel, who feared Davy would not encourage aspiring young scientists.

  Davy's authority drained away through public failures. From 1823 to 1825, helped by Faraday, he tried to protect Royal Navy copper hulls from salt-water corrosion by attaching sacrificial pieces of zinc or iron. The corrosion protection worked, but the protected copper fouled quickly, gathering weed and marine creatures that impeded the ships. By the end of 1825 the Admiralty ordered the protectors removed. He also failed to secure a Royal Medal for Babbage, alienating the reformers. In 1826 he suffered a stroke from which he never fully recovered.

  Davy is supposed to have claimed Faraday as his greatest discovery, though the line is also reported as a cruel joke at his expense. Their rivalry was real; Davy had accused Faraday of plagiarism as early as 1821, over Faraday's discovery of electromagnetic rotation. Davy set off to Italy for his health in January 1827 and was succeeded as president by Davies Gilbert. He spent his last months writing Consolations in Travel, and died in Geneva on the 29th of May 1829. His will asked for no post-mortem and for a delay before burial, to be certain he was not merely comatose; the city's ordinances did not allow the interval he wanted.