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21 Roebuck, John
SUBJECT AREA: Chemical technology[br]b. 1718 Sheffield, Englandd. 17 July 1794[br]English chemist and manufacturer, inventor of the lead-chamber process for sulphuric acid.[br]The son of a prosperous Sheffield manufacturer, Roebuck forsook the family business to pursue studies in medicine at Edinburgh University. There he met Dr Joseph Black (1727–99), celebrated Professor of Chemistry, who aroused in Roebuck a lasting interest in chemistry. Roebuck continued his studies at Leyden, where he took his medical degree in 1742. He set up in practice in Birmingham, but in his spare time he continued chemical experiments that might help local industries.Among his early achievements was his new method of refining gold and silver. Success led to the setting up of a large laboratory and a reputation as a chemical consultant. It was at this time that Roebuck devised an improved way of making sulphuric acid. This vital substance was then made by burning sulphur and nitre (potassium nitrate) over water in a glass globe. The scale of the process was limited by the fragility of the glass. Roebuck substituted "lead chambers", or vessels consisting of sheets of lead, a metal both cheap and resistant to acids, set in wooden frames. After the first plant was set up in 1746, productivity rose and the price of sulphuric acid fell sharply. Success encouraged Roebuck to establish a second, larger plant at Prestonpans, near Edinburgh. He preferred to rely on secrecy rather than patents to preserve his monopoly, but a departing employee took the secret with him and the process spread rapidly in England and on the European continent. It remained the standard process until it was superseded by the contact process towards the end of the nineteenth century. Roebuck next turned his attention to ironmaking and finally selected a site on the Carron river, near Falkirk in Scotland, where the raw materials and water power and transport lay close at hand. The Carron ironworks began producing iron in 1760 and became one of the great names in the history of ironmaking. Roebuck was an early proponent of the smelting of iron with coke, pioneered by Abraham Darby at Coalbrookdale. To supply the stronger blast required, Roebuck consulted John Smeaton, who c. 1760 installed the first blowing cylinders of any size.All had so far gone well for Roebuck, but he now leased coal-mines and salt-works from the Duke of Hamilton's lands at Borrowstonness in Linlithgow. The coal workings were plagued with flooding which the existing Newcomen engines were unable to overcome. Through his friendship with Joseph Black, patron of James Watt, Roebuck persuaded Watt to join him to apply his improved steam-engine to the flooded mine. He took over Black's loan to Watt of £1,200, helped him to obtain the first steam-engine patent of 1769 and took a two-thirds interest in the project. However, the new engine was not yet equal to the task and the debts mounted. To satisfy his creditors, Roebuck had to dispose of his capital in his various ventures. One creditor was Matthew Boulton, who accepted Roebuck's two-thirds share in Watt's steam-engine, rather than claim payment from his depleted estate, thus initiating a famous partnership. Roebuck was retained to manage Borrowstonness and allowed an annuity for his continued support until his death in 1794.[br]Further ReadingMemoir of John Roebuck in J.Roy. Soc. Edin., vol. 4 (1798), pp. 65–87.S.Gregory, 1987, "John Roebuck, 18th century entrepreneur", Chem. Engr. 443:28–31.LRD -
22 Daniell, John Frederick
SUBJECT AREA: Electricity[br]b. 12 March 1790 London, Englandd. 13 March 1845 London, England[br]English chemist, inventor of the Daniell primary electric cell.[br]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.[br]Principal Honours and DistinctionsFRS 1814. Royal Society Rumford Medal 1832, Copley Medal 1837, Royal Medal 1842.Bibliography1836, "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 ReadingObituary, 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.GWBiographical history of technology > Daniell, John Frederick
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См. также в других словарях:
Sulphuric acid — Sulphuric Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher… … The Collaborative International Dictionary of English
Fuming sulphuric acid — Sulphuric Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher… … The Collaborative International Dictionary of English
Nordhausen sulphuric acid — Sulphuric Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher… … The Collaborative International Dictionary of English
sulphuric acid — strong acid that attacks organic compounds, acid used in refining and industry … English contemporary dictionary
Sulphuric — Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher valence as… … The Collaborative International Dictionary of English
Sulphuric anhydride — Sulphuric Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher… … The Collaborative International Dictionary of English
Sulphuric ether — Sulphuric Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher… … The Collaborative International Dictionary of English
vitriolic acid — Sulphuric Sul*phu ric, a. [Cf. F. sulfurique.] 1. Of or pertaining to sulphur; as, a sulphuric smell. [1913 Webster] 2. (Chem.) Derived from, or containing, sulphur; specifically, designating those compounds in which the element has a higher… … The Collaborative International Dictionary of English
Sulfuric acid — Sulfuric acid … Wikipedia
Sludge acid — Impure dark colored sulphuric acid that has been used in the refining of petroleum. [Webster 1913 Suppl.] … The Collaborative International Dictionary of English
sulfuric acid — Chem. a clear, colorless to brownish, dense, oily, corrosive, water miscible liquid, H2SO4, usually produced from sulfur dioxide: used chiefly in the manufacture of fertilizers, chemicals, explosives, and dyestuffs and in petroleum refining. Also … Universalium
