Daniell, John Frederick

SUBJECT AREA: Electricity

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b. 12 March 1790 London, England

d. 13 March 1845 London, England

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English chemist, inventor of the Daniell primary electric cell.

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With an early bias towards science, Daniell's interest in chemistry was formed when he joined a relative's sugar-refining business. He formed a lifelong friendship with W.T.Brande, Professor of Chemistry at the Royal Institution, and together they revived the journal of the Royal Institution, to which Daniell submitted many of his early papers on chemical subjects. He made many contributions to the science of meteorology and in 1820 invented a hydrometer, which became widely used and gave precision to the measurement of atmospheric moisture. As one of the originators of the Society for Promoting Useful Knowledge, Daniell edited several of its early publications. His work on crystallization established his reputation as a chemist and in 1831 he was appointed the first Professor of Chemistry at King's College, London, where he was largely responsible for establishing its department of applied science. He was also involved in the Chemical Society of London and served as its Vice-President. At King's College he began the research into current electricity with which his name is particularly associated. His investigations into the zinc-copper cell revealed that the rapid decline in power was due to hydrogen gas being liberated at the positive electrode. Daniell's cell, invented in 1836, employed a zinc electrode in dilute sulphuric acid and a copper electrode in a solution of copper sulphate, the electrodes being separated by a porous membrane, typically an unglazed earthenware pot. He was awarded the Copley Medal of the Royal Society for his invention which avoided the "polarization" of the simple cell and provided a further source of current for electrical research and for commercial applications such as electroplating. Although the high internal resistance of the Daniell cell limited the current and the potential was only 1.1 volts, the voltage was so unchanging that it was used as a reference standard until the 1870s, when J. Lattimer Clark devised an even more stable cell.

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Principal Honours and Distinctions

FRS 1814. Royal Society Rumford Medal 1832, Copley Medal 1837, Royal Medal 1842.

Bibliography

1836, "On voltaic combinations", Phil. Transactions of the Royal Society 126:107–24, 125–9 (the first report of his experiments).

Listings of his scientific papers can be found in Catalogue of Scientific Papers, 1868, Vol. II, London: Royal Society.

Further Reading

Obituary, 1845, Proceedings of the Royal Society, 5:577–80.

J.R.Partington, 1964, History of Chemistry, Vol. IV, London (describes the Daniell cell and his electrical researches).

B.Bowers, 1982, History of Electric Light and Power, London.

GW