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 D Z U N G A R I A— E A R L Y 597 one in the tight, the other in the slack part of the belt, the beam in its central position is proportional to (P-p). If and adjusting loads on them until a stable condition of run- the angle 01 = <?2=:12Oo, Q = (P-p) neglecting friction. ning is obtained. In W. Froude’s belt dynamometer (see When a shaft is driven by means of gearing the driving Proc. Inst. ME., 1858) (Fig. 8) the guide pulleys Gj, G2 are torque is measured by the product of the resultant pressure P carried upon an arm free to turn about the axis 0. H is a pulley acting between the wheel teeth and the radius of the pitch circle to guide the approaching and receding parts of the belt to and of the wheel fixed to the shaft. Fig. 9, which has been reproduced from J. White’s A New Century of Inventions (Manchester, 1822), illustrates possibly the earliest application of this principle to dynamometry. The wheel D, keyed to the shaft overcoming the resistance to be measured, is driven from wheel N by two bevel wheels L, L, carried in a loose pulley K. The two shafts, though in a line, are independent. A torque applied to the shaft A can be transmitted to D, neglecting friction, without change only if the central pulley K is held from turning; the torque required to do this is twice the torque transmitted. The torque acting on the armature of an electric motor is necessarily accompanied by an equal and opposite torque acting on the frame. If, therefore, the motor is mounted on a cradle free to turn about knife-edges, the reacting torque is the only torque tending to turn the cradle when it is in a vertical position, and may therefore be measured by adjusting weights to hold the cradle in a vertical position. The rate at which the motor is transmitting work is then ^ H.P., where n is the revolu550 tions per second of the armature. See Dredge. Electric Illumination, vo. . London, 1885.— Beaumont, W. W. “Dynamometers and Friction Brakes,” Proc. Inst. C.E. vol. xcv. London, 1889.—Brauer, E. “ Ueber Bremsdynamometer und verwandte Kraftmesser, ” Zeitschrift des Vereins deutscher Ingenieure. Berlin, 1888.—Feather, J. J. Dynamometers and the Measurement of Power. New York, 1893. Fig. 9. (W. E. D.) from the beam in parallel directions. Neglecting friction, the Dzungaria or Jungaria, the name that unbalanced torque acting on the beam is 4r{P-p} lb ft. If a may conveniently be given to the broad trench leading OR force Q acting at R maintains equilibrium, -^ = (P-p)r=T. from the Mongolian plateau to the lowlands round Lake Q is supplied by a spring, the extensions of which are recorded Balkhash, and limited by the Eastern Altai in the north on a drum driven proportionally to the angular displacement of and the Eastern Tian-shan in the south. It was formerly the driving pulley ; thus a work diagram is obtained. Farcot has designed a form in which the guide pulleys are attached to an independent state, and has played an important part in separate weighing levers placed horizontally below the apparatus. the history of Mongolia and the great migrations of MonIn a belt dynamometer built for the Franklin Institute from the golian stems westward. Now its territory belongs partly designs of Mr Tatham, the weighing levers are separate and to the Chinese Empire (East Turkestan and North-Western arranged horizontally at the top of the apparatus. The weighing beam in the Hefner-Alteneck dynamometer is placed trans- Mongolia) and partly to Russian Turkestan (provinces of versely to the belt (see Electrotechnischen Zeitschrift, Heft 7,1881). Semiryechensk and Semipalatinsk). See Mongolia and The force Q, usually measured by a spring, required to maintain East Turkestan.

Eads, James Buchanan (1820-1887), American engineer, was born at Lawrenceburg, Indiana, on 23rd May 1820. His first engineering work of any importance was in raising sunken steamers. In 1845 he established glass works in St Louis. During the Civil War he constructed ironclad steamers and mortar boats for the Federal Government. His next important engineering achievement was the construction of the great steel arch bridge across the Mississippi at St Louis (see Encyclopaedia Britannica, vol. xxi. p. 185), upon which he was engaged from 1867 till 1874. The work, however, upon which his reputation principally rests was his deepening and fixing the channel at the mouths of the Mississippi by means of jetties, whereby the narrowed stream was made to scour out its own channel and carry the sediment out to sea. (See vol. xx. pp. 580, 581.) Shortly before his death he projected a scheme for a ship railway across the Isthmus of Tehuantepec, in lieu of an isthmian canal. He died at Nassau, in the Bahamas, on 8th March 1887. Eaglehawk, a borough of Victoria, Australia, in the county of Bendigo, 4 miles north-north-west of Bendigo city, with which it is connected by steam tramway. It has a fine park, with lake, of 40 acres. There are valuable gold mines in the district. Altitude, 735 feet. Population (1881), 7362; (1901), 8130.

Ealing, a suburb of London, England, in the Ealing parliamentary division of Middlesex, 9 miles west of St Paul’s, with two railway stations. There are seven Established churches (in St Mary’s, 1770, are buried Oldmixon, the historian, and Horne Tooke). Other buildings are public offices, with library and science and art schools, a high school for girls, a training college for teachers of the deaf, an isolation hospital, and a cottage hospital and dispensary. There is a common and a public park. Among former distinguished residents of Ealing were Henry Fielding, the novelist, and John, first duke of Marlborough. Area of urban district, 2928 acres. Population (1881), 15,769 ; (1891), 23,979; (1901), 33,040. Ear. See Pathology and Physiology {special senses). Early, Jubal Anderson (1816-1894), American soldier and lawyer, was born in Franklin county, Va., on 3rd November 1816, and graduated at the U.S. military academy in 1837. After a brief service he resigned in July 1838, to practise law in Virginia, but as major in a regiment of state volunteers took part in the Mexican War. In 1861 he entered the Confederate service as a colonel, fought at Bull Run (July 1861), received a wound at Williamsburg (May