With regard to manufacture, a brief account of the Krupp process as applied in one of the great English armour plate works (omitting confidential details of temperature, &c.) will illustrate the great complexity of treatment which the modern armour plate has to undergo before its remarkable qualities of combined hardness and toughness can be developed. The composition of the steel probably differs slightly with the manufacturer, and also with the thickness of the armour, but it will usually contain from 3 to 4% of nickel, from 1.0 to 2.0% of chromium and about 0.25 to 0.35% of carbon, together with from 0.3 to 0.7% of manganese. After being cast, the ingot is first heated to a uniform degree of temperature throughout its mass and then generally forged under the hydraulic forging press. It is then reheated and passed through the rolls. After rolling, the plate is allowed to cool, and is then subjected to a thermal treatment preparatory to surfacing and cutting. Its surface is then freed from scale and planed. After planing, the plate is passed into the cementation furnace, where its face remains for some weeks in contact with specially prepared carbon, the temperature being gradually raised to that required for cementation and as gradually lowered after that is effected. After cementation the plate is heated to a certain temperature and is then plunged into an oil bath in order to toughen it. After withdrawal from the oil bath, the plate is cooled, reheated to a lower temperature, quenched again in water, reheated and passed to the bending press, where it is bent to shape while hot, proper allowance being made for the slight change of curve which takes place on the final chilling. After bending it is again heated and then allowed to get cold, when the final machining, drilling and cutting are carried out. The plate is now placed in a furnace and differentially heated so that the face is raised to a higher temperature than the back. After being thus heated for a certain period the plate is withdrawn, and both back and face are douched simultaneously with jets of cold water under pressure, the result being that the face is left glass-hard while the back is in the toughest condition possible for such hard steel. Entry: FIG
In this development of manufactures, the mineral resources have been an important influence, nearly one-fourth (23.6%) of the manufactured product in 1900 depending upon minerals for raw material. Although the iron ore, for the iron and steel industry, is furnished by the mines of the Lake Superior region, bituminous coal and limestone are supplied by the Illinois deposits. The great central coal field of North America extends into Illinois from Indiana as far N. as a line from the N. boundary of Grundy county to Rock Island, W. from Rock Island to Henderson county, then S.W. to the southern part of Jackson county, when it runs S. into Kentucky, thus including more than three-fourths (42,900 sq. m.) of the land surface of the state. In 1679 Hennepin reported deposits of coal near what is now Ottawa on the Illinois; there was some mining in 1810 on the Big Muddy river in Jackson county; and in 1833, 6000 tons were mined. In 1907 (according to state authorities) coal was produced in 52 counties, Williamson, Sangamon, St Clair, Macoupin and Madison giving the largest yield. In that year the tonnage was 51,317,146, and the value of the total product $54,687,882; in 1908 the value of the state's product of coal was exceeded only by that of Pennsylvania (nearly six times as great). Nearly 30% of all coal mined in the state was mined by machinery in 1907. The output of petroleum in Illinois was long unimportant. The first serious attempts to find oil and gas in the state were in the 'fifties of the 19th century. In 1889 the yield of petroleum was 1460 barrels. In 1902 it was only 200 barrels, nearly all of which came from Litchfield, Montgomery county (where oil had been found in commercial quantities in 1886), and Washington, Tazewell county, in the west central part of the state; at this time it was used locally for lubricating purposes. There had been some drilling in Clark county in 1865, and in 1904 this field was again worked at Westfield. In 1905 the total output of the state was 181,084 barrels; in 1906 the amount increased to 4,397,050 barrels, valued at $3,274,818; and in 1907, according to state reports, the output was 24,281,973 barrels, being nearly as great as that of the Appalachian field. The petroleum-producing area of commercial importance is a strip of land about 80 m. long and 2 or 3 to 10 or 12 m. wide in the S.E. part of the state, centring about Crawford county. In April 1906 the first pipe lines for petroleum in Illinois were laid; before that time all shipments had been in tank cars. In connexion with petroleum, natural gas has been found, especially in Clark and Crawford counties; in 1906 the state's product of natural gas was valued at $87,211. Limestone is found in about 30 counties, principally Cook, Will and Kankakee; the value of the product in 1906 was $2,942,331. Clay and clay products of the state were valued in 1906 at $12,765,453. Deposits of lead and zinc have been discovered and worked in Jo Daviess county, near Galena and Elizabeth, in the N.W. part of the state. A southern district, including parts of Hardin, Pope and Saline counties, has produced, incidentally to fluorspar, some lead, the maximum amount being 176,387 lb. from the Fairview mine in 1866-1867. In 1905 the zinc from the entire state was valued at $5,499,508; the lead product in 1906 was valued at $65,208. Sandstone, quarried in 10 counties, was valued in 1905 at $29,115 and in 1906 at $19,125. Pope and Hardin counties were the only sources of fluorspar in the United States from 1842 until 1898, when fluorspar began to be mined in Kentucky; in 1906 the output was 28,268 tons, valued at $160,623, and in 1905 33,275 tons, valued at $220,206. The centre of the fluorspar district was Rosiclare in Hardin county. The cement deposits are also of value, natural cement being valued at $118,221 and Portland cement at $2,461,494 in 1906. Iron ore has been discovered. Glass sand is obtained from the Illinois river valley in La Salle county; in 1906 it was valued at $156,684, making the state in this product second only to Pennsylvania and West Virginia (in 1905 it was second only to Pennsylvania). The value of the total mineral product of the state in 1906 was estimated at $121,188,306.[2] Entry: ILLINOIS
_Methods of Engraving_ (see also under LAPIDARY).--In gem-engraving the principal modern implement is a wheel or minute copper disk, driven in the manner of a lathe, and moistened with olive oil mixed with emery or diamond dust. There is no clear proof of the use among the ancients of a wheel mounted lathewise, but we have abundant indications of drilling with a revolving tool, which might be either a tubular drill making a ring-like depression, a pointed tool making a cup-like sinking, or a small wheel with a cutting edge, making a boat-shaped depression. Entry: 2
CHANUTE, a city of Neosho county, Kansas, U.S.A., 1 m. from the Neosho river, and about 120 m. S.S.W. of Kansas city. Pop. (1890) 2826; (1900) 4208, of whom 210 were foreign-born and 171 were negroes; (1910 census) 9272. Chanute is served by the Atchison, Topeka & Santa Fe and the Missouri, Kansas & Texas railways, the former having large repair shops. The city is in the Kansas-Oklahoma oil and gas field, and is surrounded by a fine farming and dairying region, in which special attention is given to the raising of small fruit; oil, gas, cement rock and brick shale are found in the vicinity. Among the city's manufactures are refined oil, Portland cement, vitrified brick and tile, glass, asphalt, ice, cigars, drilling machinery, and flour. The municipality owns and operates the waterworks, a natural gas plant, and an electric lighting plant. Four towns--New Chicago, Tioga, Chicago Junction and Alliance--were started here about the same time (1870). In 1872 they were consolidated, and the present name was adopted in honour of Octave Chanute (b. 1832), the civil engineer and aeronautist (see FLIGHT AND FLYING), then the engineer of the Lawrence, Leavenworth & Galveston railway (now part of the Atchison system). Chanute was incorporated as a city of the third class in 1873, and its charter was revised in 1888. Natural gas and oil were found here in 1899, and Chanute became one of the leaders of the Kansas independent refineries in their contest with the Standard Oil Company. Entry: CHANUTE