Bar iron

“ The patent further describes that "as the workman stirs the metal," the scoriae will separate, "and the particles of iron will adhere, which particles the workman must collect or gather into a mass or lump." This mass or lump was then to be raised to a white heat, and forged into malleable iron at the forge-hammer.
Such was the stage of advance reached in the manufacture of bar-iron, when Henry Cort published his patents in 1783 and 1784. In dispensing with a blast, he had been anticipated by the Craneges, and in the process of puddling by Onions ”

“ The quantity of iron now produced in England, exceeds that furnished by the rest of the world united, and does not fall short of 800,000 tons. It has a value even in its raw state of near four millions sterling, and is of far greater intrinsic worth, in consequence [Pg 373] of the spur which its abundance gives to every other branch of industry.
Bar iron is at the present day principally manufactured from the pig. The process originally used for this purpose is called refining. The fire in which it is performed is a forge, similar in form and character to that employed in blooming. ”

“ The iron bar performance necessitates the employment of a mixture of chemicals, with which the parts exposed to the red-hot metal are anointed. If the bar is not up to red-heat, the feat is dangerous, as the chemicals will not act. The dancing on the bar must be gone through rapidly, the heel of the foot never resting for a moment on the iron.
My acrobatic and fire-king feats I have long since discontinued, and for many years my sword-swallowing has been subordinate to the less romantic business by which I gain my living. ”

“ It is impossible to assign the limits between these three forms of iron, or their relative proportions of carbon, with ultimate precision; for bar iron passes into steel by insensible gradations, and steel and cast iron make such mutual transitions as to render it difficult to define where the former commences, and the latter ceases, to exist. In fact, some steels may be called crude iron, and some cast irons may be reckoned among steels. ”

“ The sheet iron so popular in America for parlor stoves and stove pipe, comes from Ekaterineburg and its vicinity, and is made from magnetic ore. The bar iron of the Urals is famous the world over for its excellent qualities, and commands a higher price than any other. Great quantities of iron are floated in boats down the streams flowing into the Kama and Volga. Thence it goes to the fair at Nijne Novgorod, and to the points of shipment to the maritime markets. ”

“ If a thin piece of bar iron be packed in powdered charcoal and heated at low red heat for some time, the metal, 113after cooling, will be found to have acquired the hardening property. In other words by absorption of carbon it will have become steel with all of the characteristics of that material. Neither the iron nor the carbon by which it was surrounded have melted, yet in some way carbon has penetrated into the iron and if the heating has been sufficiently long, carbon will be found at the center of the bar. ”

“ They are formed under the tilt-hammer, and differ in substance from bar-iron in nothing, except that, having been imperfectly forged, the fibres of the metal are not fully extended, nor firmly united. The blooms are manufactured in the interior of the country, where wood is abundant, and sold by the ton, frequently, in the cities, to be converted into bar or sheet iron. ”

“ Steel appears to contain but half the quantity of carbon in its chemical proportions that white cast iron does, but, like it, is susceptible of a variety of mixtures; if the proportion of carbon amount to three per cent., it loses the property of malleability, if the proportion fall as low as one per cent. it can no longer be tempered, and is identical with the harder varieties of bar-iron. ”

“ As might naturally be expected, the principal ironmasters, when they heard of Cort's success, and the rapidity and economy with which he manufactured and forged bar-iron, visited his foundry for the purpose of examining his process, and, if found expedient, of employing it at their own works. Among the first to try it were Richard Crawshay of Cyfartha, Samuel Homfray of Penydarran (both in South Wales) , and William Reynolds of Coalbrookdale. Richard Crawshay was then (in 1787) forging only ten tons of bar-iron weekly under the hammer ”

“ Hunter's, at Fredericksburgh, makes about 300 tons a year of bar iron, from pigs imported from Maryland; and Taylor's forge on Neapsco of Patowmac, works in the same way, but to what extent I am not informed. The indications of iron in other places are numerous, and dispersed through all the middle country. The toughness of the cast iron of Ross's and Zane's furnaces is very remarkable. Pots and other utensils, cast thinner than usual, of this iron, may be safely thrown into, or out of the waggons in which they are transported. ”

“ About the close of the last century the great improvement in the manufacture of bar-iron was introduced by passing it through grooved rollers, instead of hammering it on the anvil; but in our own time the invention has become most important. ”

“ I think not, as channeled iron is in almost as common use as bar iron, and hardly any framed work is made where stiffness and lightness are required but that it is used, because it is the stiffest form in which iron can be used in carrying a load between two points, either suspended or in the form of a _____; and wherever a compressible strain occurs, or cross-strain, or any other strain than a purely tension strain, it is the cheapest iron to use, and it is in common use under such circumstances. ”

“ Bars of wrought iron are packed in layers, each bar surrounded by charcoal, and the whole hermetically sealed in a fire-brick vessel luted on top with clay; heat is then applied until the whole is brought up to a bright orange color, and this heat is maintained as evenly as possible until the whole mass of iron is penetrated by carbon; usually bars about three quarters of an inch thick are used, and the heat is required to be maintained for three days, the carbon, entering from both sides, requiring three days to travel three eighths of an inch to the centre of the bar. ”

“ Thus, when combined with carbon, in varying proportions, substances are produced, so different, but each so valuable, that they might almost be regarded in the light of distinct metals,—such, for example, as cast-iron, and cast and bar steel; the various qualities of iron enabling it to be used for purposes so opposite as a steel pen and a railroad, the needle of a mariner's compass and an Armstrong gun, a surgeon's lancet and a steam engine, the mainspring of a watch and an iron ship, a pair of scissors and a Nasmyth hammer, a lady's earrings and a tubular bridge. ”

“ During the melting of the charge the heat is kept as high as possible and the molten iron is “puddled,” i. e., stirred, by the “puddler” or his helper with a “rabbler” or iron bar. In order to take out the phosphorus and sulphur, which for best results should be removed before the carbon is eliminated, the heat of the furnace is lowered somewhat as soon as all of the pig has melted, and some iron oxide is mixed into the “bath” of molten iron and cinder. Most of the phosphorus and sulphur are chemically acted upon and pass into the cinder which covers the iron. ”

“ The celebrated mines of Danemora produce the finest Swedish iron, and only a limited quantity is allowed to be produced each year. All the steel-iron used in England is imported into Hull. Bar-steel is manufactured by heating the iron, divided into lumps, in pots, with layers of charcoal, closely covered over with sand and clay, for several days. By this means the iron is carbonized and converted into what is commonly called blistered steel. The heat is kept up a longer or shorter time according to the hardness required. ”

“ Whereas iron has a value in itself considered. It fells the forest, tills the soil, annihilates time and distance, and underlies the whole economy of domestic life; for our readers will bear in mind that steel is only another form of iron.
[Pg 19]
The value iron acquires under the hammer is something wonderful. It is said that a bar of iron worth $5 is worth $10.50 when made into horse-shoes, $55 when made into needles, $3,285 made into penknife blades, $29,480 in shirt buttons, and $250,000, in balance springs of watches. ”

“ One has no difficulty in realizing that these flakes, which cut in every direction through the metal, make it structurally weak, especially toward a sudden blow.
No. 1d shows a typical section of wrought iron cut lengthwise of the rolled bar. It will be noted that, as in photomicrograph No. 99b, there are no graphite flakes.
In the process of wrought iron manufacture practically all of the carbon of the original pig iron is burned out, leaving little besides the iron itself and some viscous cinder or slag. ”

“ Steel has no fiber and for this reason it cannot be split as was the wrought iron bar shown in the illustration of page 92.
It will have been noticed that only small amounts of iron can be refined at one time. This, indeed, has been the unfortunate part of wrought iron manufacture, for it may readily be seen that production of any such material in lots as small as a quarter ton results in labor costs which are almost prohibitive in these days of machine-made goods. Not only is the output of a furnace small but much skill and judgment are necessary for the production of a high grade product. ”

“ This may be wrought out as in Fig. 5. The use of a bar of iron or steel is as shown. The bar is usually about 2 in. in diameter and several feet in length, so that it will rest firmly on a base of wood or stone. Then the bending is effected as at F, about the bar E, by repeated blows with the hammer. After a little practice, it is possible to describe almost any kind of a circle with the tools. The bar can be bought at an iron dealers for about 40 cents. From the junk pile of junk shop one may get a like bar for a few cents. ”

“ Heat can also be produced by the impact of imperfectly elastic bodies as well as by friction. This is the case, for instance, when we produce fire by striking flint against steel, or when an iron bar is worked for some time by powerful blows of the hammer. ”

“ On the application of heat in furnaces, constructed for the purpose, the charcoal unites with the oxygen of the oxide, reducing it to the metallic state, and escapes in the form of carbonic acid; and the lime, if the ore be argillaceous, unites with the clay, forming a kind of glass, which floats on the melted metal. When the iron is suffered to run into moulds, prepared for its reception, it usually takes the name of pig iron.
Manufacturers distinguish cast iron by its colour and other qualities. The white cast iron is hard and brittle, and can neither be filed, bored, nor bent. ”

“ He worked with difficulty, and slowly, as he could not see, and was obliged to feel the iron, and cool it repeatedly to ascertain whether it was as he desired it.
"Look here, Glory!" he said, "when iron is taken from the smelting furnace it is crystalline and brittle; there is no thread and texture in it, but we burn it and beat it, and as we work we beat our stubborn purpose into the metal, and it is the will of the smith which goes through his arm and hammer into the iron and converts it to steel; he drives his will into the metal, and that becomes the fibre in it. ”

“ In some works 16 tons or more of iron are treated in one operation. The bars are found unchanged in form, but increased in weight by perhaps 27 lbs. per ton, for carbon has combined with the iron, being apparently transferred in the iron from one particle to another. The surface of the bars becomes rough and uneven from a multitude of blebs or blisters, and hence they are called blister bars, and the steel of which they now consist is named blister steel. ”

“ Manufactured irons differ very greatly amongst themselves. For one kind is tenacious in its nature, and this is the best; one is of medium quality: another is brittle, and this is the worst. Sometimes the iron, by reason of the excellency of the ore, is wrought into steel, as to-day in Noricum. From the finest iron, too, well wrought and purged from all dross, or by being plunged in water after heating, there issues what the Greeks call στόμωμα ”

“ Billy looked at him questioningly.
“That was rather technical, wasn’t it, Billy? You see, I was talking to a technical man. Just between you and me, meteoric iron comes down from the sky, from what we call shooting stars. Sometimes large pieces are found. I suppose that much of it falls into the sea. It is the purest iron that has ever been found.”
“What about magnetic iron?” asked Dr. Crandon. “Where does that come from?”
“At the present time,” answered Mr. Prescott, “most of it comes from Sweden and Norway. It makes the best kind of steel. ”

“ Prescott, “just remember three things: fuel, blast, and hammer—power, of course, behind the hammer. It’s the different variations that men have been making on those three things that have brought iron where it is to-day.
“Iron ore has so many things besides iron in it that the problem has always been how to get the impurities out.
“The old blacksmiths used to put it in the fire and hammer it; put it back in the fire and hammer again, until they worked most of the other things out. They made what is called forge iron. ”

“ There are many modifications of these general rules and methods, and it may be necessary in certain cases, such as the ironing of braids stiffened with media other than gelatine or water soluble materials, to employ other methods, but they are generally peculiar to the plait used and of a purely ephemeral nature. In some factories box irons are used, heated by patent fuel, others are warmed by gas and electricity, but the general convenience of the fire-heated pad causes the old fashioned iron to retain an almost universal supremacy. ”