coke, substance obtained by the destructive distillation of bituminous coal. Coke bears the same relation to coal as does charcoal to wood. A hard, gray, massive, porous fuel, coke is the solid residue remaining after bituminous coal is heated to a high temperature out of contact with air until substantially all components that easily vaporize have been driven off. The residue is chiefly carbon, with minor amounts of hydrogen, nitrogen, sulfur, and oxygen. Also present in coke is the mineral matter in the original coal, chemically altered and decomposed.

Since the vapor-producing constituents are driven off during coke production, coke is an ideal fuel for stoves and furnaces in which the environment is unsuitable for the complete burning of bituminous coal itself. In the form of oven coke it is primarily used when a porous fuel with few impurities and high carbon content is desired, as in the blast furnace to make iron. Coke is also used in other metallurgical processes, such as the manufacture of ferro-alloys, lead, and zinc, and in kilns to make lime and magnesium. Exceptionally large strong coke is known as foundry coke and is used in foundry cupolas to smelt iron ores. The smallest sizes of coke are used to heat buildings.

The majority of coke produced in the United States comes from byproduct coke ovens. The coke is prepared in retorts or furnaces of silica brick, and the byproducts (chiefly ammonia, coal tar, and gaseous compounds) are saved. These volatile gases are collected and sent to the byproduct plant where various byproducts are recovered. In nonrecovery coke plants, originally referred to as beehive ovens, the coal is carbonized in large oven chambers; the partially combusted gases collect in a common tunnel and exit via a stack. In recovery coke plants the waste gas exits into a waste heat recovery boiler which converts the excess heat into steam for power generation.

Petroleum coke is the solid residue left by the cracking process of oil refining. Natural coke, or carbonite, is formed by metamorphism from bituminous coal when intrusive igneous rock cuts across a vein of coal.

Leicester, Thomas William Coke, earl of: see Coke, Thomas William.

Coke, Thomas William, 1752-1842, English agricultural reformer. Created earl of Leicester of Holkham in 1837, he was known as Coke of Holkham. He improved breeds of cattle, sheep, and hogs on his country estate and greatly promoted improved methods of breeding and husbandry.

Coke, Thomas, 1747-1814, English clergyman and early bishop of the Methodist Episcopal Church in America. After taking orders (1777) in the Church of England, he openly allied himself with the Methodists. He was president of the Irish conference in 1782 and two years later was ordained as superintendent for America by John Wesley. When Coke was styled bishop shortly after the American conference of 1784, the change was not approved by Wesley. Coke visited America nine times, the last time in 1803. Always deeply interested in Methodist missionary work, he sought (1813) an appointment by the government as bishop of India, agreeing to return to the Established Church. As the request was not granted, he himself secured funds for a Methodist mission, but died on the way to Ceylon (Sri Lanka).

Coke, Sir Edward, 1552-1634, English jurist, one of the most eminent in the history of English law. He entered Parliament in 1589 and rose rapidly, becoming solicitor general and speaker of the House of Commons. In 1593 he was made attorney general. His rival for that office was Sir Francis Bacon, thereafter one of Coke's bitterest enemies. He earned a reputation as a severe prosecutor, notably at the trial of Sir Walter Raleigh, and held a favorable position at the court of King James I. In 1606 he became chief justice of the common pleas. In this position, and (after 1613) as chief justice of the king's bench, Coke became the champion of common law against the encroachments of the royal prerogative and declared null and void royal proclamations that were contrary to law. Although his historical arguments were frequently based on false interpretations of early documents, as in the case of the Magna Carta, his reasoning was brilliant and his conclusions impressive. His constant collisions with the king and the numerous enmities he developed—especially that with Thomas Egerton, Baron Ellesmere, the chancellor—brought about his fall. Bacon was one of the foremost figures in engineering his dismissal in 1616. By personal and political influence, Coke got himself back on the privy council and was elected (1620) to Parliament, where he became a leader of the popular faction in opposition to James I and Charles I. He was prominent in the drafting of the Petition of Right (1628). His most important writings are the Reports, a series of detailed commentaries on cases in common law, and the Institutes, which includes his commentary on Littleton's Tenures.

Solid residue remaining after certain types of coals are heated to a high temperature out of contact with air until substantially all components that easily vaporize have been driven off. The residue is chiefly carbon, with minor amounts of hydrogen, nitrogen, sulfur, and oxygen. Also present in coke is the mineral matter in the original coal, chemically altered and decomposed. The gradual exhaustion of timber in England had led first to prohibitions on cutting of wood for charcoal and eventually to the introduction of coke. Thereafter the iron industry expanded rapidly and Britain became the world's greatest iron producer (see Abraham Darby). The crucible process (1740) resulted in the first reliable steel made by a melting process. Oven coke (about 1.5–4 in., or 40–100 mm, in size) is used in blast furnaces to make iron. Smaller quantities of coke are used in other metallurgical processes (see metallurgy), such as the manufacture of certain alloys. Large, strong coke, known as foundry coke, is used in smelting. Smaller sizes of coke (0.6–1.2 in., or 15–30 mm) are used to heat buildings.

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(born Feb. 1, 1552, Mileham, Norfolk, Eng.—died Sept. 3, 1634, Stoke Poges, Buckinghamshire) British jurist and politician. He became a lawyer in 1578 and was made solicitor general in 1592. His advance to the position of attorney general (1594) frustrated his great rival, Francis Bacon. As attorney general, he conducted several famous treason trials, prosecuting Robert Devereux, 2nd earl of Essex, and Henry Wriothesley, 3rd earl of Southampton (1600–01); Sir Walter Raleigh (1603); and the Gunpowder Plot conspirators (1605). Named chief justice of the Court of Common Pleas in 1606, Coke earned the ire of James I by declaring that the king's proclamation could not change the law (1610). He upset church leaders by limiting the jurisdiction of ecclesiastical courts. Appointed chief justice of the King's Bench by James I (1613), he remained unswayed; he hinted at scandal in high places and defied a royal injunction in a case involving ecclesiastical privileges. He was dismissed in 1616, partly through Bacon's efforts. In 1620 he reentered Parliament (he had served in 1589), where he denounced interference with Parliament's liberties (1621) until he was imprisoned. In 1628 he helped frame the Petition of Right, a charter of liberties; this defense of the supremacy of the common law over royal prerogative had a profound influence on the English law and constitution. On his death his papers were seized by Charles I. His Reports (1600–15), taken together, are a monumental compendium of English common law, and his Institutes of the Lawes of England (4 vol., 1628–44) is an important treatise.

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(born Feb. 1, 1552, Mileham, Norfolk, Eng.—died Sept. 3, 1634, Stoke Poges, Buckinghamshire) British jurist and politician. He became a lawyer in 1578 and was made solicitor general in 1592. His advance to the position of attorney general (1594) frustrated his great rival, Francis Bacon. As attorney general, he conducted several famous treason trials, prosecuting Robert Devereux, 2nd earl of Essex, and Henry Wriothesley, 3rd earl of Southampton (1600–01); Sir Walter Raleigh (1603); and the Gunpowder Plot conspirators (1605). Named chief justice of the Court of Common Pleas in 1606, Coke earned the ire of James I by declaring that the king's proclamation could not change the law (1610). He upset church leaders by limiting the jurisdiction of ecclesiastical courts. Appointed chief justice of the King's Bench by James I (1613), he remained unswayed; he hinted at scandal in high places and defied a royal injunction in a case involving ecclesiastical privileges. He was dismissed in 1616, partly through Bacon's efforts. In 1620 he reentered Parliament (he had served in 1589), where he denounced interference with Parliament's liberties (1621) until he was imprisoned. In 1628 he helped frame the Petition of Right, a charter of liberties; this defense of the supremacy of the common law over royal prerogative had a profound influence on the English law and constitution. On his death his papers were seized by Charles I. His Reports (1600–15), taken together, are a monumental compendium of English common law, and his Institutes of the Lawes of England (4 vol., 1628–44) is an important treatise.

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