P L U P L U 231 lished that plumbago is simply an impure form of native carbon. Plumbago is principally used in the manufacture of " black-lead " pencils, for which purpose it was at one time very extensively worked at Borrowdale in Cumber land. It was known locally as " wad," and a grant of the manor of Borrowdale, as far back as the reign of James L, refers to " the wad-holes and wad, commonly called black cawke." The Cumberland plumbago is found in pipes, strings, and irregular masses known as " sops, " which occur in a dyke of diorite, associated with a compact blue diabase, penetrating some of the altered ash-beds of the volcanic series. Important mines of plumbago, yielding fine pencil lead, were opened some years ago by M. Alibert in the government of Irkutsk in eastern Siberia. A good deal of plumbago is also worked near Passau in Bavaria. The graphite so largely used, when mixed with fire-clay, in the manufacture of " black-lead " crucibles, is obtained chiefly from Ceylon ; and it is notable that, notwithstand ing the purity of the Ceylon plumbago, it is not applicable to the manufacture of lead pencils. Large quantities of plumbago occur in the Laurentian limestones of Canada ; while in the United States the mineral is worked at Sturbridge, Mass. ; at Ticonderoga and Fishkill, KY. ; at Brandon, Vt.; and at Wake, N.C. It was formerly yielded by the mines of Ashford in Connecticut. Among the minor applications of plumbago may be mentioned its use as a lubricating agent for machinery and for polishing cast iron. In the preamble to an Act for protecting the black-lead mines of Cumberland, 25 Geo. II. c. 10, it is stated that plumbago is necessary " for clivers useful pur poses, and more particularly in the casting of bomb-shells, round shot, and cannon balls." It was formerly held in repute in medicine, and a writer on the Cumberland plumbago in 1709 asserts " It s a present remedy for the cholick ; it easeth the pain of gravel stone and strangury ; and for these and the like uses it s much bought up by apothecaries and physicians." It is notable that plumbago is occasionally found in masses of meteoric iron, and that a substance of similar physical and chemical characters is produced in the blast-furnace during the preparation of cast iron, and is known to the workmen as kisk. Plum bago bears a strong resemblance to the mineral termed molybdenite, while it resembles to a less extent certain varieties of micaceous iron-ore ; the molybdenite, however, is easily distinguished by giving a slightly greenish streak, while the iron-ore yields a red streak. For the mineral ogical characteristics of plumbago or graphite, see vol. xvi. p. 381 ; for its chemical relations, vol. v. p. 86 ; and for its use in crucible-making, vol. ix. p. 843. PLUNKET, WILLIAM CONYNGHAM PLUNKET, BAROX (1765-1854), an eminent lawyer, orator, and statesman, was born in the county of Fermanagh in July 1765. He vas educated in boyhood by his father, a man of considerable ability and reputation ; and in 1779 he became a student of Trinity College, Dublin. Though well versed in regular academic studies, he was most conspicuous in his university career as the acknowledged leader of the Historical Society, the debating club of Trinity College, then full of young men of remarkable promise. Having entered Lincoln s Inn in 1784, Plunket was called to the Irish bar in 1787. His intellect was exactly that of a jurist or a great master of equity not too refin ing or overprone to speculation, and yet capable of the highest legal generalizations, and of applying them to masses of fact, however tedious and complicated. His power of close and rapid argument was very remarkable, his ^ memory equally capacious and exact, and he had enriched an ample store of professional learning with the fruits of assiduous general study. Although at first his progress at the bar was not rapid, he gradually obtained a considerable practice in equity ; and, after an apprentice ship of eleven years as a junior, he was raised to the rank of king s counsel in 1798. In 1798 he entered the Irish parliament as member for Charlemont. His political faith was already settled, and was only slightly modified in after life, at least as regards its cardinal tenets. He was an anti-Jacobin Whig of the school of Burke, not ungracefully filled with a fervent Irish patriotism. He disliked the principles of the French Revolution, and its excesses made such an impression upon him that he always showed the greatest antipathy to merely democratic movements. But he was a sincere admirer of the constitutional government of England as established in 1688 ; he even justified the ascendency it had given to the Established Church, although he thought that the time had arrived for extending toleration to Roman Catholics and dissenters. To transfer it to Ireland as thus modified, and under an independent legislature, was even in his youth the only reform he sought for his country; and, although he opposed the Union with all his power, this was only because he thought it incompatible with this object. When Plunket became a member of parliament, the Irish Whig party was almost extinct, and Pitt was feeling his way to accomplish the Union. In this he was seconded ably by Lord Castlereagh, by the panic caused by a wild insurrection, and by the secession of Grattan from politics. When, however, the measure was actually brought forward, it encountered a vehement opposition ; and among the ablest and fiercest of its adversaries was Plunket, whose powers as a great orator were now universally recognized. His speeches in these debates show all the force of reason ing, the admirable arrangement, and the grasp of facts which characterize his later efforts ; but they are some what disfigured by personal invective, and here and there betray an indecent acrimony. They raised him, however, immediately to the front rank of his party ; and, when Grattan re-entered the moribund senate, he took his seat next to Plunket, thus significantly recognizing the place the latter had attained. After the union of Great Britain and Ireland Plunket returned to the practice of his profession, and became at once a leader of the equity bar. In 1803, after the out break of Emmet s rebellion, he was selected as one of the crown lawyers to prosecute the unfortunate enthusiast, and at the trial, in summing up the evidence, delivered a speech of remarkable power, which shows his characteristic dislike of revolutionary outbursts. For this speech he was exposed to much unmerited obloquy, and more espe cially to the abuse of Cobbett, against whom he brought a successful action for damages. In 1804, in Pitt s second administration, he became solicitor-general and then attor ney-general for Ireland; and he continued in office when Lord Grenville came into power at the head of the ministry of All the Talents. Plunket held a seat in the imperial parliament during this period, and there made several able speeches in favour of Catholic emancipation, and of continuing the war with France ; but, when the Grenville cabinet was dissolved, he returned once more to professional life, and for some years devoted himself exclusively to it. In 1812, having amassed a considerable fortune, he re- entered parliament as member for Trinity College, and identified himself thoroughly with the Grenville or anti- Gallican Whigs. He was now in the full maturity of his powers, and very soon was acknowledged one of the first orators, if not the first, of the House of Commons. His reverence for the English constitution in church and state, his strong dislike of French principles, his steady advocacy of the war with Napoleon, and his antipathy to anything like democracy made him popular with the Tory party.
On the other hand, he was the zealous and most able sup-