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 DEWAR —DEWEY tinned to discharge the delicate duties of the leader of a middle party with no less judgment than he had shown Avhen leading the Liberals during the interregnum of 1875-80. It was not until 1895, when the differences between Conservatives and Liberal Unionists had become almost obliterated by changed circumstances and the habit of acting together, that the duke of Devonshire, as he had become by the death of his father in 1891, consented to enter Lord Salisbury’s third Ministry as President of the Council. The duke thus was the nominal representative of education in the Cabinet at a time when educational (questions were rapidly becoming of great importance; and the duke’s own technical knowledge of this difficult and intricate question being admittedly superficial, a good deal of criticism from time to time resulted. His great contribution to public life, however, has been the weight of character which procured for him universal respect and confidence, and exempted him from bitter attack, even from his most determined political opponents. No man ever doubted the duke of Devonshire’s patriotism, or felt entirely secure in differing from his judgment. Wealth and rank combined with character to place him in a measure above party: and he remained a luminous example of the benefit which a democratic community may derive from the existence within it of an aristocratic class and the participation of its members in public affairs. The duke succeeded his father as Chancellor of the University of Cambridge in 1892, and is a Knight of the Garter. Dewar, James (1842 ), British chemist and physicist, was born at Kincardine-on-Forth, Scotland, on 20th September 1842. He was educated at Dollar Academy and Edinburgh University, being at the latter first a pupil, and afterwards the assistant, of the late Lord Playfair, then professor of chemistry; he also studied under Kekule at Ghent. In 1875 he was elected Jacksonian professor of natural experimental philosophy at Cambridge, becoming a fellow of Peterhouse, and in 1877 he succeeded Dr J. H. Gladstone as Fullerian professor of chemistry in the Royal Institution, London. He ha,s been president of the Chemical Society and of the Society of Chemical Industry, served on the Balfour Commission on London Water Supply (1893—94), and as a member of the Committee on Explosives (1888—91) invented cordite jointly with Sir Frederick Abel. His scientific work covers a wide field. Of his earlier papers, some deal with questions of organic chemistry, others with Graham’s hydrogenium and its physical constants, others with high temperatures, e.g., the temperature of the sun and of the electric spark, others again with electro-photometry and the chemistry of the electric arc. With Professor M‘Kendrick, *i of Glasgow, he investigated the physiological action of light, and examined the changes which take place in the electrical condition of the retina under its influence. With Professor G. D. Liveing, one of his colleagues at Cambridge, he began in 1878 a long series of spectroscopic observations, the most recent of which have been devoted to the spectroscopic examination of various gaseous constituents separated from atmospheric air by the aid of low temperatures. Since the time that liquid air and liquid oxygen have been available in considerable quantities, he has been joined by Professor J. A. Fleming, of University College, London, in the investigation of the electrical behaviour of substances cooled to very low temperatures. His name is most widely known in connexion with his work on the liquefaction of the so-called permanent gases and his researches at temperatures approaching the zero of absolute temperature. His interest in this branch of inquiry dates back at least as far as 1874, when he discussed the “Latent Heat of Liquid

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Gases” before the British Association. In 1878 he devoted a Friday evening lecture at the Royal Institution to the then recent work of Cailletet and Pictet, and exhibited for the first time in Great Britain the working of the Cailletet apparatus. Six years later, in the same place, he described the researches of Wroblewski and Olszewski, and illustrated for the first time in public the liquefaction of oxygen and air, by means of apparatus specially designed for optical projection so that the actions taking place might be visible to the audience. Soon afterwards he constructed a machine from which the liquefied gas could be drawn off through a valve for use as a cooling agent, and he showed its employment for this purpose in connexion with some researches on meteorites , about the same time he also obtained oxygen in the solid state. By 1891 he had designed and erected at the Royal Institution an apparatus which yielded liquid oxygen by the pint, and towards the end of that } ear he showed that both liquid oxygen and liquid. ozone are strongly attracted by a magnet. About 1892 the idea occurred to him of using vacuum-jacketed vessels for the storage of liquid gases, and so efficient did this device prove in preventing the influx of external heat that it is found possible not only to preserve the liquids for comparatively long periods, but also to keep them so free from ebullition that examination of their optical properties becomes possible. He next experimented with a high-pressure hydrogen jet by which low temperatures were realized through the Thomson-Joule effect, and the successful results thus obtained led him to build the large refrigerating machine by which in 1898 hydrogen was for the first time collected in the liquid state, its solidification following in 1899 (see Liquid Gases). The Royal Society in 1894 bestowed the Rumford Medal upon Professor Dewar for his work in the production of low temperatures, and in 1899 he became the first recipient of the Hodgkins Gold Medal of the Smithsonian Institution, Washington, for his contributions to our knowledge of the nature and properties of atmospheric air. Dewas, a native state of India, in the Indore agency. For more than a century the state has been divided, almost equally, between the descendants of a former chief, known as the senior and junior branches, or as Baba and Dada Saheb. Both live in the town of Dewas, but exercise exclusive jurisdiction over their several shares. Total area, 289 square miles. Population (1881), 142,162; (1891), 152,073, showing an increase of 7 per cent., which has been almost confined to the share of the senior branch ; average density, 526 persons per square mile. The chiefs are Rajputs of the Puar clan, of the same family as the Raja of Dhar. The two chiefs ruling in 1901 ivere named Krishnaji Rao and Mulhar Rao, these names showing Maratha influence. The town of Dewas is situated in 22° 58' N. lat. and 76° 6' E. long., about 20 miles north-east of Indore. Population, 11,921. It has a high school and a hospital. Dewey, George (1837 ), American naval commander, was born in Montpelier, Vt., on 26th December 1837, and graduated at the U.S. Naval Academy in 1858. In the Civil War he served as lieutenant on the steam sloop Mississippi, during Farragut’s passage of the forts below New Orleans in April 1862, and at Port Hudson in March 1863. After the war he performed various routine duties, rising in grade to commodore (February 1896). On 30th November 1897 he was assigned, at his own request, to sea service, and sent to Asiatic waters. Being notified by telegraph in April 1898, while with his fleet at Hong Kong, that war had been declared with