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nable. Such are found at Grafton, Athens, exercise an important, and it may be at times Westfield, and Marlborough, Vt.; at Frances- a useful, influence upon the properties of the town, Pelham, Keene, and other towns in New metal in its application to special purposes. Hampshire; at Middlefield, Chester, and other Nitrogen, according to Prof. R. Marchand, is alplaces in Massachusetts; between Baltimore ways present to the amount of about } per cent., and Washington in Maryland; in Loudon co., associated with about 3 times as much carbon. Va., Guilford co., N. O., and numerous other In iron nitrogen is found by Schaufhäutl in places unworked on the range of the metamor- proportions varying from 0.532 to 1.2 per cent., phic rocks through the southern states. The in white pig; and in all the processes of prorock is sawed into slabs and used for jambs for ducing steel, as affirmed by Mr. O. Binks in a fireplaces, for lining stoves, or for the whole paper read before the society of arts in 1857, stove. After being heated it takes a good pol- nitrogen in some form must be present.—The ish and assumes an apple-green color. It is following are some of the properties of steel. also turned in lathes for various articles, and is When broken it exhibits in the fracture a graybored for water pipes; formerly it was much ish color, lighter than that of iron; its structure used for inkstands. The sizing rollers in cot- is granular, and in the best steel is very fine. ton factories are made of soapstone, for which This is produced by condensation by hammerit is especially adapted from not being affected ing or rolling, and is accompanied by a susby acids nor liable to change of form by vary- ceptibility of receiving a high polish, which is ing temperatures; the rollers are sometimes much less liable to be affected by rust than a 4 feet long and 6 inches in diameter. The polished iron surface. The metal is inferior to stone has been pulverized to be used with iron in ductility and malleability, and is worked other materials in the manufacture of porce- down under the hammer or rolled with much lain; it makes the biscuit semi-transparent, greater difficulty. When balanced upon the but brittle. The powder is especially useful as hand and struck with a hammer, it gives a clear a lubricant for the journals of heavy wheels, ringing sound, indicating by its peculiar intoand is also used as a polishing material for ser- nation to the practised ear the quality of the pentine, alabaster, &c. It is the basis of cog- metal. It acquires a higher degree of elasticimetic powders and of certain crayons. The ty than any other solid body, and is hence best spotted steatite, cut into cameos and calcined, adapted for a great variety of springs. It is assumes an onyx aspect. The softer varieties more slow than iron to become magnetic, but make excellent stoppers for the chemical appa- retains this property more tenaciously. Its ratas used in distilling or subliming corrosive melting point is given as 2,786° F., which is vapors. By the American aborigines soap- considerably higher than that of cast iron, and stone was found to be a convenient and useful lower than that of wrought iron. It is not material for culinary utensils, and many of the adapted for casting into moulds of intricate ancient relics now met with are of this easily form, as well by reason of the high temperacarved stone. The Chinese have employed it ture of its melting point, as on account of its so generally for their idols and other figures not thus acquiring the density and toughness connected with their religious rites, that it has which these forms may require, and which are sometimes been known as the “figure stone." imparted to steel bars by subsequent processes

STEEL, a variety of iron, distinguished for of hammering and rolling. Steel may be weldthe extreme and varying degrees of hardnessed, but with more difficulty than wrought iron, of which it is susceptible, and for possessing at especially if it has been first melted or cast; the same time the fusible property of cast iron in this case a thin film of borax should be inand the malleability and welding property of terposed between the surfaces to be united. A wrought iron. Some notice of it has already perfect union may be effected between wrought been given under Iron, and some of its most re- iron and steel by placing a bar of the former, markable properties are treated in the article with one surface well polished, in the mould inDAMASCUS BLADES. In composition it holds a to which the steel is cast. The two metals thus place intermediate between wrought or malle- united, when rolled out, are sometimes employable iron and cast iron; the first being simply ed for chisels, plane irons, &c., one face being iron; steel, iron with 1 to 13 per cent. of car- of steel and forming the cutting edge, while bon; and cast iron containing about 4 per cent. the other being of iron insures the greatest of carbon. As the proportion of carbon in steel toughness. A steel plate is rapidly cut by the increases, the metal approaches cast iron in its edge of a disk of soft iron, made to revolve with properties, becoming hard and brittle, and in- great velocity. Intense heat is generated at the creasing in fusibility; but with diminishing points of contact, and the particles of steel are proportions of carbon it assumes more and thrown off in a state of ignition. The iron is more of the softness, toughness, and mallea- very little worn or otherwise affected. Cast iron bility of wrought iron. Those steels of the cannot be thus cut. The most striking peculiarformer character are designated as high, and ity of steel is the different degrees of hardness it those of the latter as low or mild. Other sub- assumes by changes of temperature. When heatstances beside carbon, that are sometimes pres- ed to redness and slowly cooled it is not much ent to a very small amount, are commonly re- harder than iron, but by sudden cooling it is garded as impurities; although some of them rendered very hard and brittle ; and the higher

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the temperature to which it is raised and the writers called the same substance acies, and ferri more sudden the cooling, the greater is the acies, whence the French acier, steel. Beckhardness. On this principle is based the pro- mann affirms on the authority of Hesychius that cess of tempering, by which any desired degree the term adamas originally meant steel, and of hardness is obtained. The different tempera- should be so translated when applied to chains, tures are indicated by a succession of colors bars, gates, &c. Yet it is remarkable that no which the metal takes while heating, and these articles of steel have been found among the colors consequently serve to direct the work- relics of the nations of antiquity, even to the man who seeks to obtain the hardness that is period of the Roman empire. The iron and steel appropriate for certain uses. Thus a very pale of India are both mentioned by ancient writers, straw color, corresponding to 430° F., is the and the latter is supposed to be the same as thé right color for lancets; a deeper shade, 450°, wootz, of which 100 talents, called ferrum canis adapted for razors and most surgical instru- didum, were presented to Alexander in India, ments; an orange yellow, 470°, for penknives; and which is still prepared there by a very prima brownish yellow, 490°, for cold-chisels ; á itive method. The Hindoos charge their crucibrownish yellow tinged with purple, 510°, forbles with bits of malleable iron, mixed with wood plane irons; a purple, 530°, for table knives and covered with the leaves of trees, which, and scissors; a pale blue, 550°, for swords and when the metal is thoroughly heated, furnish watch springs; a common blue, 560°, for fine the carbonaceous and nitrogenous elements Baws and dirks; very deep blue black, 600°, for of the steel. Fusion ensues, and the steel, of pit saws. At 630° it becomes sea-green, but very superior quality for fine cutlery, is finally above this temperature the colors disappear, found in a button at the bottom of the crucible. and if slowly cooled the steel becomes very During the middle ages the art of making steel soft, so that it can be worked with ease, after existed in the highest perfection in Turkey and which it may be tempered as desired. A more the countries of the East; but in western Euexact method of tempering than by the color is rope it was comparatively little known. At to immerse the steel in heated baths of mercu- Eisenärz in Styria it has been practised ever ry or of oil, the temperature of which is care- since the 8th century. Even as late as the fully regulated according to the indications of 17th century few persons practised it in Engthe thermometer, graduated up to the boiling land, and the first patent granted for this manpoint of mercury. The cooling may be effected ufacture was dated April 8, 1626, to Richard by plunging the articles into cold water, into Lord Dacre, Thomas Letsome, and Nicholas cold mercury, or oil, or if they are very small by Page, for “ apparatus for making steel," acwaving them through the air. By hardening cording to the invention of Letsome. Foreign steel its volume is increased.—The early histo- iron alone was used for it. About 1670 menry of steel is involved in much obscurity. It tion is made of steeling articles by “boiling is supposed that the substance was known to them in sow-metal.” The carbon of this is the ancient Egyptians, and that articles made given up to the wrought iron articles in suffiof it were designated in their drawings by a cient quantity to convert them into steel; and blue color. In the Hebrew language there is by Vanaccio this was carried so far that the no word specially applicable to it; but it is sup- cast metal was also brought down to the steel posed the hard "iron from the north,” spoken point, making however poor steel. This is of in Jeremiah xv. 12, may have been steel probably the same operation that is spoken of from Chalybia, a country famous for its iron by Agricola, Imperati, and others, as practised production. There are several allusions in the at an earlier period on the continent. The old Greek authors to the hardening of a metal, manufacture by cementation is said to have commonly understood to be steel, by plunging been practised at Bromley by John Heydon as it when hot in cold water; thus when Ulysses early as 1697, but was first made generally pierced the eye of Polyphemus with a burning known by Réaumur, and described in his work stick, Homer describes the hissing as like that on steel published in 1722 (see RÉATMUR); and of red-hot iron when plunged by the smith into cast steel, it is stated, was first made by Mr. water to harden it. Aristotle describes the Huntsman at Attercliff, near Sheffield, in 1770. processes of the Chalybes by which they con- The subject attracted some attention in the verted iron into steel, purifying it from the Connecticut colony as early as 1655, when the scoriæ by a succession of meltings. The word assembly of New Haven granted privileges to otowua, applied to the new product, is used by John Tucker of Southold, Long island, who unvarious Greek writers to designate something dertook the manufacture. There is no record distinct from olònpos, iron, and, when described however of his succeeding in it. Joseph Higat all, having the peculiar hardness and uses of by, an ingenious blacksmith of Granby, Conn., steel. Daimachus, a writer contemporary with who also distinguished himself by his coin'Alexander the Great, names under the same age of the Granby coppers, memorialized the 'designation four varieties of steel: the Chalyb- legislature of Connecticut in 1727, that he had dic, suitable for carpenters' tools; the Lace- “ with great pains and cost found out and dæmonian, for files, drills, gravers, and stone obtained a curious art, by which to convert, chisels; the Lydian, for the same and also for change, or transmit common iron into good knives and razors; and the Synopic. The Latin steel, sufficient for any use, and was the very first that ever performed such an operation in required for 100 of steel. In Westphalia lamAmerica.” He produced samples of good steel, ellar manganesian white irons, which are rapand obtained a patent for 10 years.-Steel is idly refined, are treated for steel in furnaces obtained, first, either directly from iron ores, like the retinery fires. The cast iron is thrown. the carbon being infused into the iron as this in, in quantities of about 75 lbs. at a time, and is revived from the natural oxides; or, second, when sufficiently refined the loops are taken out from east iron, by removing from it a portion of and drawn down under the hammer. The steel the carbon it contains; or, third, from bar iron, is used for making scythes, cutlery, and swords, by causing this to absorb a due proportion of after being well refined. In the New Jersey carbon; and in procuring it from each kind of iron region, and in that of N. New York, pudmanufactured iron several processes are em- dled steel has been made to some extent. The ployed. From certain rich magnetic ores steel best charcoal iron is required for the purpose, may be worked in a small way directly, even and manganese is sometimes added to the in the blacksmith's forge; and in the Catalan charge, the purpose it serves being apparently furnace the manufacture has been carried on to lengthen out the time of the refining, and upon a considerable scale. When this is the thus diminish the risk of passing the desired special object of the operation, the process of point of decarbonization. The process rereduction is somewhat varied, with the view quires much care and skill on the part of of checking the decarbonizing action before it the workman, and the product is rather & is carried to the point of malleable iron. The steely iron, or mixture of steel and iron, and operation is stopped at a point determined by this of varying and uncertain quality, than good esperience, when the loop is removed and steel. Whether puddled steel has ever been drawn out into bars under the hammer. By cast or not is uncertain. It is supposed that long continued hammering the steel thus ob- this may be done in Krupp's works at Estained may be made to acquire a tolerably uni- sen, which will again be referred to. Other form density and composition; but a more ex- methods of treating cast iron for steel will peditious method is to convert it into cast steel be mentioned, after describing the process in by melting in crucibles, in which condition it general use of producing steel from bar iron. is kept from 3 to 4 hours, when it is poured out Nearly all the steel of commerce is prepared into east iron moulds. The method is not from bar iron by what is called the “cementalargely practised, owing to the want of uni- tion process." It consists in exposing the formity in the product.--Among the methods iron, buried in charcoal, to long continued of treating cast iron for steel, that of partial heat. The operation is conducted in a furrefining by puddling has been long practised nace resembling externally that used in the in Isère in S. E. France, in Thuringia, West- glass manufacture, in the base of which, under phalia, Styria, and Carinthia. What is known an arch, are set two horizontal troughs made of in this country as German steel, produced from fire slabs, each of them from 8 to 15 feet long, pig iron made from spathose iron ores, is chiefly and from 26 to 36 inches wide and deep. Bar puddled steel carefully refined. In Isère the iron, made from magnetic ores with charcoal, is cast iron, usually gray, sometimes a sublamellar selected for making the best steel, and the Engwhite iron, is first melted in a furnace with a lish works are supplied with such iron from single tuyère, together with rich scoriæ of the Sweden and Russia, the choicest brands being preredling operation, with charcoal. The iron is slowly brought to the melted state, and is those known as hoop 1, D; GL, & ; and the thus kept about 8 hours. The refining then double bullet, 00; all produced from the ores commences, and lasts about 6 hours. The tem- of the famous Danemora mine. These irons perature is kept lower than in ordinary refining are worth in England from £30 to £33 per ton, fires. just sufficient for the scoriæ to remain in and, with other irons imported from Sweden, & fluid condition. The charge is worked up Russia, and Norway, are used in the manufacwith a ringer, as in ordinary puddling, and the ture of steel to the extent of 35,000 tons annuoxygen which removes the carbon from the cast ally. The poorer English steel irons, worth £11 iron is in part derived from the oxide of iron of per ton, are used to the extent of about 20,000 the scoriæ. To check its too rapid action the tons. The bars are cut into lengths somewhat draught is diminished and silicious sand is shorter than the troughs, and a bed for them thrown in. Steel “comes to nature" at the being prepared in these about an inch deep, of surface, forming a spongy crust. This is broken pulverized hard wood charcoal mixed with op, pushed toward the extreme end of the fur- its weight of ashes and a little common salt, the Dace, and formed into little loops of 30 or 40 bars are laid in this edgewise, about half an inch pounds weight each. As these are produced apart. The charcoal mixture or “ cement" is about one every 10 minutes, they are taken then sifted over the bars and pressed between out and hammered into blooms. About 8 them, so that each one is in contact with nothbours are required to remove the whole charge ing else. When the bars are covered about an of about a ton weight, making 22 hours for the inch deep, another tier is added, each bar over whole operation. The blooms are afterward the space between two bars of the bottom layheated in a separate fire, and then drawn down er. The same packing with cement is repeated, into bars. About 132 parts of cast iron are and other tiers are added in the same manner,

till the chests are filled within 3 inches of the in many large establishments in Sheffield, Engtop.

This space is then closed in with cement land, and both the blistered and shear steels from a previous operation, and covered over are sold, to be converted by other manufaceither with damp silicious sand or with fire turers into the various objects of their operslabs, the joints plastered with fire clay. A ations.—But steel is carried to a still higher complete charge is commonly about 15 tons; degree of perfection by another operation, some furnaces hold 18 to 20 tons. In the end which converts it into what is known as cast of the chests some of the bars in the centre are steel. This consists in melting in crucibles the made to project through openings left for the bars of blistered steel, broken in pieces of a purpose and through the brickwork in front, pound weight or less. The furnaces, one for the object being to draw them out in the course each crucible, are partly sunk below the floor of the process for indicating its progress. The of the foundery, and are intensely heated by fire is started and gradually increased for the coke, or in the United States by anthracite. first 24 hours, and after this the heat is kept at The largest measure about 20 inches by 16, and about 100° of Wedgwood's pyrometer, neces- are 3 feet deep. The crucible, charged the first sarily below the fusing point of steel. In 6 days time used with 36 lbs. of metal, the second time the first examination is made, and in 2 more the with 32 lbs., and the third and last time with bars are commonly found to be converted into about 30 lbs., is introduced from the top upon blistered steel, so called from the blisters all over the grate bars in the midst of the fuel; and its surface, produced it is supposed by the insin- the cover being put on the fire is driven by the nation of carbon beneath scales of the metal im- strong blast derived from the high chimney, perceptibly united to the mass; it has also been and kept up from 3 to 4 hours. The crucible is suggested that in the imperfectly welded places then lifted out, and its contents are poured into oxide of iron is formed, the oxygen of which the cast iron ingot moulds. The ingots are uniting with the infiltrated carbon produces car- hammered or rolled into bars or sheets, and the bonic oxide and lifts up the metallic scale. The steel thus obtained is of the hardest and densbars gain about zoo in weight and about to in est character, requiring much care in forging length. From the manner in which the carbon that it is not hammered at a heat above a cheris introduced, the steel cannot be homogeneous, ry red, when it is in danger of being broken to but contains most carbon in its outer portions. pieces. It is made into bars of various shapes If soft steel is wanted for springs and saws, the and qualities, and is very largely produced in process may be stopped several days sooner than Sheffield for domestic use and exportation. if a higher steel is required, suitable for files, Great care is taken to insure a uniform quality chisels, and other cutting tools. The fire is stop- in each sort of steel sent to market, and also ped and the furnace is left for about two weeks the exact quality suited to the particular use to cool before the bars can be taken out. They for which the steel is designed. Each ingot is may then be applied to a variety of ordinary pur- not only examined to insure its uniform charposes, as some agricultural instruments, table acter, but it is also appropriated to the special cutlery, coach springs, &c.; but to produce steel use for which, according to its tenacity and of good quality other operations are necessary. hardness, it is found to be adapted. Many imWhat is called shear steel, so named from its portant tools require a particular grade of steel, having been originally employed in the manu- and constant practice and long experience are facture of shears for dressing woollen cloth, is necessary to appreciate the differences of qualimade from fagoted pieces of bars of blistered ty. But notwithstanding all this care large steel, heated to a full welding heat, in which lots are occasionally returned to the makers they are protected from oxidation by a coating by manufacturers in this country, who find the of very fine clay, and drawn down under the steel ill adapted to their purposes, although tilt hammer to a bar two inches square, or any from the same houses that have previously other desired size. The tilt hammer for finish- supplied them satisfactorily. It is not strange ing the small bars weighs only from 150 to 200 then that consumers are unwilling to incur lbs., and is so constructed as to be worked with the risk of trying a new variety, especially great rapidity, striking from 200 to 300 blows a when so many instances are before them of minute, thereby keeping up the heat in the bar failure on the part of novices to produce conthrough the intense friction produced among tinuously good steel of uniform quality. Evthe particles of the metal. Heavier hammers ery one therefore who engages in this manuare also used, with heads faced with steel and facture does so in the face of serious difficulweighing about a ton each. By this operation ties, not merely in producing a good article, the steel is much condensed, and rendered of but in getting it recognized as such, and a sale uniform quality and homogeneous structure established for it. The most important improvethroughout. Its tenacity, malleability, and duc- ment introduced of late years in the manufactility are increased, and it becomes susceptible ture resulted from the experiments of Mr. Heath of a high polish. By doubling the bar and re- of Sheffield, who sought to produce with Engpeating the operation the character of the metal lish iron steel like that made with the Swedish. is still further improved, and it is then known The great difference in their qualities, it was as double shear steel. The manufacture up to thought, might be owing to manganese, which this point is carried on upon an extensive scale was always present in the Swedish iron. In The great

1839 he succeeded in producing a carburet of ly, resulting in homogeneous steel of the softest manganese, which caused the English iron to quality. As the oxide of iron gives up its oxymake good steel. He patented the process, but gen to carry off a portion of the carbon from not the improvement he made upon it of using the cast iron, it is itself reduced to the metallic the carbon and manganese separately. This the state, and adds to the quantity of steel obtainSheffield manufacturers adopted, and between ed, which is thus somewhat greater than of the 1839 and 1855 it has been estimated that the cast iron employed. The mixture for prosaving to the buyers of Sheffield cast steel goods ducing 25 lbs. of steel consists of 24 lbs. of by reduced prices in consequence of this inven- granulated iron, 4 lbs. of spathose ore, 4 lbs. of tion has been equal to £2,000,000. But Mr. Heath oxide of manganese, and a little clay. The was no more benefited than was Cort for in- conversion is completed in 2 to 3 hours, when troducing the puddling process; and he died the steel is poured into the moulds. The method in 1850 poor and broken-hearted. Among the is improved for irons of inferior quality by new processes of making steel, that of Besse- adding a portion of alkaline earths to the mer (see Iron ManUFACTURE, vol. ix. p. 607) charge, the effect of which is to remove the has attracted the greatest attention. It ap- impurities which readily combine with these pears to be still on probation in Europe, and is as the granules melt.-Other methods of despoken of as being tested in works especially carbonizing cast iron to the steel point are also built for the purpose in Sheffield. Little is practised. One consists in melting together stated as to the cost of the steel made by this proper proportions of bar and cast iron for the process, or of its uniformity of character; but carbon contained in the latter to produce the some of the steel produced by it possesses sort of steel desired, when it is divided througha wonderful tensile power. A bar 3 inches out the whole of the iron. A patent was grantsquare was bent round until the outer curve ed for it a few years since to G. Brown, of was lengthened from 12 to 163 inches, and Swinton. He mixes in a crucible small pieces of the inner lessened from 12 to 77 inches, cold charcoal, with pieces of bar iron and of pig iron. and without a flaw. Four iron rods, 17 inches For a 40 lb. ingot, the proportion of cast iron in diameter, were twisted cold into a cable; varies from 7 to 12 lbs., according to the sort the rods stretched 1 foot in 4 during the pro- of steel, mild or high, required. cess, and thinned out in inverse proportion. A proportion of the charge is necessarily bar iron, steel bar 2 inches square was twisted cold into a and whenever this is to be melted great expense spiral at an angle of 45°. A round steel bar was is incurred in crucibles, the best standing only hammered cold into the form of a horse shoe. 2 or 3 heats. The best sorts of iron must be The manufacture of steel by this process is re- employed, there being no provision for sepaported to be carried on in several localities in rating and removing the noxious elements usuSweden, especially by Daniel Elfstrand and co. ally present.--A method of converting malleaof Edsken; and by Mr. Göranson of Gefle in ble iron into steel by fusing it in the presence Sweden large steel circular saw plates have of an alkaline cyanide, has within a few years been made from ingots cast direct from the past been introduced into practice upon a large fluid metal within 15 minutes of its leaving the scale in the vicinity of New York. For a long blast furnace. The old firm of James Jackson time it has been known to workers in steel and and son near Bordeaux, France, is also reported iron that the latter might be superficially hardto have adopted this process in preference to ened by fusing upon it the cyanide of potasthe manufacture of steel by puddling; and it sium; but it was not known that steel might was also about being adopted at 4 blast fur- thus be made in the large way until the fact naces belonging to other establishments in the was demonstrated by Prof. A. K. Eaton, who, south of France. In Belgium and Sardinia it while lecturing upon chemistry at Little Falls, was also about being introduced.- What is N. Y., was led to engage in a course of experiknown as the Uchatius process was introduced ments in this direction. He first studied the in 1856 by Captain Uchatius, engineer of the action of cyanogen, a gaseous compound of imperial arsenal at Vienna, and consists in melt- carbon and nitrogen, upon incandescent iron; ing in crucibles cast iron reduced to small and then of the solid compounds of this gas in particles and intimately mixed with some com- the form of the cyanide or ferrocyanide of pound of iron and oxygen. Brown spar or the potassium (prussiate of potash) and cyanide of spathose protocarbonate of iron, with some ox- sodium. He found that iron raised to a bright ide of manganese, was found to be well suited red heat in a porcelain tube, or otherwise for the purpose. The quantity of oxide is grad- protected, was rapidly and perfectly converted nated to furnish just the amount of oxygen into steel, by passing over it cyanogen gas; required. The cast iron is granulated by caus- also that iron wire introduced into the flame of ing it, as it flows from the blast furnace, to be a burning jet of cyanogen was similarly changed dashed and scattered by the floats of a wheel by absorption of carbon. Bars of iron were from which it falls into cold water, and the then packed in fine charcoal with an admixture smallest pieces are preferred, even such as of yellow prussiate of potash or other cyanide, weigh 1,000 to the pound. The most intimate and at a high temperature these in a surprisingmixture is thus effected, and the chemical ly short time were thoroughly converted into change takes place most readily and thorough- steel. The object of the charcoal is explained

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