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 246 PENDLETON HORIZONTAL PENDULUM ite or black lead, are among the most widely distributed manufactures. The best graphite for drawing pencils is in the Cumberland mines, England. Vast quantities also have been found in Siberia of a very fine quality. But graph- ite is rarely found so free from impurities as to form pencils homogeneous enough to be relied on by the artist. It is therefore finely pulverized and again formed into solid blocks by the application of great pressure, usually in hydraulic presses. Great difficulty was expe- rienced in consolidating the particles and caus- ing them to adhere without using some cement, by which the quality would be injured. This was at last accomplished by Mr. Brockedon of London, who after subjecting the material to considerable pressure enclosed it in a case of glued paper with an orifice, placed it under the receiver of an air pump, and exhausted the air. Then by a contrivance the orifice in the glued paper was closed, and the block removed and subjected to further pressure, when it be- came as solid as a natural block from the mine. The pencils are made by sawing the block into square bars, inserting these in grooves of cor- , responding size cut in pieces of wood, covering them with other pieces of wood, and reducing these by machinery to the desired shape, which is usually that of a cylinder, but it may be hexahedral or octahedral. The maker's name, and letters or numbers indicating the degrees of hardness, fineness, or depth of shade, are then stamped upon them. t PENDLETON. I. A N. E. county of West Vir- ginia, bordering on Virginia, enclosed between two ranges of the Alleghanies, and intersect- ed by the S. branch of the Potomac and two of its tributaries ; area, about 800 sq. m. ; pop. in 1870, 6,455, of whom 94 were colored. Its surface is mountainous and covered with for- ests, and the soil not very fertile. The chief productions in 1870 were 37,984 bushels of wheat, 10,594 of rye, 59,228 of Indian corn, 14,538 of oats, 56,876 Ibs. of butter, 26,273 of wool, and 5,079 tons of hay. There were 1,767 horses, 2,270 milch cows, 5,155 other cattle, 9,943 sheep, and 4,246 swine. Capital, Frank- lin. II. A N. county of Kentucky, bordered N. E. by the Ohio, and intersected by the Lick- ing; area, 300 sq. m. ; pop. in 1870, 14,030, of whom 641 were colored. It has an undulating and well wooded surface and fertile soil. It is intersected by the Kentucky Central railroad. The chief productions in 1870 were 37,203 bushels of wheat, 19,355 of rye, 578,938 of In- dian corn, 46,560 of oats, 29,453 of potatoes, 161,343 Ibs. of butter, 24,948 of wool, and 1,651,593 of tobacco. There were 4,269 horses, 2, 774 milch cows, 3,665 other cattle, 7,307 sheep, and 18,752 swine. Capital, Falmouth. PENDLETON, Edmund, an American statesman, born in Caroline co., Va., Sept. 9, 1721, died in Richmond, Oct. 23, 1803. He began his career as an apprentice in the clerk's office of Caroline co., in 1740 was made clerk of the county court martial, and in 1741 was licensed to practise law. In 1751 he became one of the county justices, and in 1752 was elected to the house of burgesses. In 1764 he was one of the com- mittee appointed to memorialize the king, and in 1773 of the committee of correspondence. In 1774 he was elected to the colonial conven- tion, consequent on the Boston port bill, and chosen by that convention to the first congress. In 1775 he presided over the colonial conven- tion, and was appointed president of the com- mittee of safety. In May, 1776, he again pre- sided in the convention, and drew up the cele- brated resolution of that body instructing the delegates from Virginia to propose in congress a declaration of independence. After the in- auguration of the commonwealth he was called to preside over the first house of delegates, and was appointed by that body, in conjunc- tion with Chancellor Wythe and Mr. Jefferson, to revise the colonial laws. He was the head of the committee of safety during the early part of the war. In March, 1777, by a fall of his horse, he received an injury of the hip joint which made him a cripple for life. In the same year he was reflected speaker of the house of burgesses. On the organization of the chancery court that year, he was unani- mously elected its president ; and when, in 1779, the court of appeals was constituted, he also became its president. This last post he held till his death. He presided over the state con- vention of 1788, in which was to be considered the proposed constitution of the United States, and was a leading advocate of its adoption. PENDS D'OREILLES. See KALISPELS. PENDULUM. See CLOCKS AND WATCHES, and MECHANICS. PENDULUM, Horizontal, an instrument for measuring very weak attractive or repulsive forces ; it can also be used for measuring slight changes of level, or minute variations in the dimensions of solid bodies. It combines the advantages of the ordinary pendulum with those of the torsion balance. The former in- strument may be considered as a one-armed lever, which is retained in a vertical position by the attraction of gravitation ; when acted on by an attractive or repulsive force in any except a vertical direction, it tends to be de- flected from its normal position, and if the force be sufficiently powerful, an actual change of position will be observed. But this deflec- tion can be accomplished only by lifting the pendulum bodily through a distance measured by the versed sine of the arc of deflection, and it is this fact which deprives the ordinary pen- dulum of sensitiveness to the action of weak attractive or repulsive forces. On the other hand, the ordinary pendulum obeys equally well a force emanating from a point in its im- mediate neighborhood, and that of one proceed- ing from an infinite distance, provided only these forces are virtually equal with respect to it ; in other words, the distance of the point from which the force emanates exercises no effect on the final action, except to weaken it