Though men have used iron for over 2,000 years, even today there is something magical about the word steel, and processes by which
it is made. Iron is strong and tough. Steel, which is a form of iron, is stronger, tougher, and far more useful. For centuries men knew that
steel was iron to which something had been added. Men observed, as they made steel, that the iron was being changed, but they could
not explain the nature of these changes. Some people thoought that the changes were caused by witchcraft. At a later time, the alchemist
claimed that it was their spells and incantations that chaged the iron into steel. And the famous steel sword blades made during the middle
ages in Toledo (Spain) and Damascus (Syria) were also thought to be produced by some sort of magical process. Although we manufacture
millions of tons of steel each year, we are still studying and improving the methods of making it. But as late as the 18th century, when
scientists first began to study steel, only small quantities could be made. and the art of making steel was still largely guesswork. The metal
workers of England and North-America kept searching for a formula that would enable them to make steel cheaply and in large quatities
It is not to be wondered, therefore, that in the mid-19th century a method of making huge batches of good steel was found in both countries,
almost simultaneousy. What was the method? First, let us understand that except for the bits of iron that occasionally fall to earth in the form
of meteors, we find almost no metallic iron. What we do find are huge supplies of iron ore. The ore looks like rust and consists of iron
combined with oxigen be a chemical change and most of the impurities must be removed. The oxygen is removed by melting the ore in a blast
furnace, in the presence of carbon. This carbon in the form of charcoal or of coke, burns away in combination with oxygen in the air and
the oxygen that was part of the iron. But some of the carbon remains mixed with the iron.
We now know the variations in the small amount of carbon that remains can cause enormous differences in the properties of the iron that is
obtained. Wrought iron, which has almost no carbon, is comparatively soft and manageble. Cast iron contains about the most carbon that
iron will absorb, and is hard and brittle. Between the two, in carbon content, lies steel. Large differences in the properties of the steel can be
obtained by slightly changing the amout of carbon it contains and by adding small amounts of other elements. Iron-making begins in a blast
furnace. Into the top of the tall furnace are dumped iron ore, limestone, and coke. A blast of air speeds the burning process and gives the
furnace its name. As the ore melts, most of the impurities combine with the limestone and rise to the top as slag. The melted iron is heavier
than the slag and settles to the bottom of the blast furnace. It is drawn off and allowed to cool in molds shaped like a small pig-hence the
term pig iron.
Pig iron is high in carbon contents and impurities. To make cast iron products, pig iron is re-heated and cast in molds. Wrought iron is made
in bloomery or pudding furnace, where the mixture is stirred to remove the carbon. In early America this iron was used for nails,
horseshoes and grillwork. Wrought iron is shaped while it is red-hot. All through the Appalachian Mountains and in
New England, there were iron deposits and great forests. The area around the city of Pittsburgh was particularly rich in iron.
Pittsburgh was the gateway to the west when John Kelly, an Irish refugee, came to America in the year 1801.
But John Kelly was not interested in iron. He became a real estate man. His sons grew up and received their education in Pittsburgh.
One of his sons, William, turned to the study of metallurgy.
The elder Kelly was a good business man. He persuaded his two sons, William and John, to own a wholesale and retail dry goods
company in Pittsburgh. While traveling to acquire accounts for the company, William met and married the daughter of a wealthy
tobacco merchant in Eddyville, Kentucky. Having studied metallurgy, William became intersted in the superior iron ore of the area.
He persuaded his brother to sell the dry goods business and buy a foundry. The two brothers went to manufacturing cast iron kettles
that were used in the sugar mills in Cuba.
After a year or two of using the surface ore, the brothers found that the ore below the surface was not of good quality. Besides, the nearby
forests were beginning to disappear because of the great quantities of wood use to make the charcoal needed in the foundaries. The
Kellys were planning to move nearer to Pittsburgh, when william made his great discorery.
One day, while working with a mass of malten iron, Willam noticed that a spot had become white-hot even though there was no fire
near it. There was just a current of air blowing over the spot. Kelly deduce that oxigen in the air had combined with carbon in the iron.
This burning of the carbon explained the white-hot spot. it also meant that a blast of air could be used to speedily burn up excessive
carbon in the iron. If just enough carbon remained, the iron would be chaged into steel. Kelly called this method of making steel the
pneumatic process. But he did not, at this point, know how to make steel in quantities. He needed time to perfect the process.
When Kelly told his family of his great discorery, they thought he was crazy. "Whoever heard," they asked, "of blowing on anything to
keep it hot? you blow on your coffee to cool it, don't you?. Other ironworkers shook their heads and muttered that Kelly would be trying to
burn ice next. His father-in-law did not like Kelly's obsession with steel. He even thought of taking his money out of his son-in-law's
business. There was so much talk that Kelly decided to work on his process in secret. He set up a hidden foundry in the woods, where he
could work in peace. At the same time, to keep everybody else happy. He worked on his iron kettles in the conventional manner.
In 1856, Kelly learned that Henry Bessemer, an English inventor, had applied for an American patent for steel-making and for a converter.
The converter was a large crucible capable of holding fifteen tons. It tilted up to a vertical position to receive a charge of molten iron.
Air blast forced through perforations in the bottom of the converter removed the carbon. After the carbon was removed, the converter
tilted down to a horizontal position to permit the refined iron, now steel, to be poured off. Kelly, alarmed, fastened to apply for a patent on his
pneumatic process and after much delay the court granted it to him. This did not prevent Bessemer from getting the patent for his converter.
Kellty later built a converter to demonstrate his process. Although Kelly had gained his patent, his troubles were not over. He went bankrupt
in the panic of 1857, and he was forced to give up his patent to his father-in-law in return for money with which to build a converter to
demonstrate the process.
The crowd that assembled to watch the trial called him "Crazy Kelly". On the first attempt, the engineer blew too strong a blast of air and
everything in the converter flew out. The crowd laughed and called it "Kelly's fireworks". Kelly tried again. This time only sparks flew
from the converter. Then the air was shut off and the molten metal was poured. Kelly hammered out a thin sheet of steel. The jokers were
now silent. They gazed in awe, hardly able to believe what their own eyes had seen. After that Kelly had no trouble getting backers.
Alexander Holley, who had bought the American rights to the Bessemer converter, offered Kelly half a million dollars for the pneumatic
process. Kelly accepted. However, the Kelly name did not appear as the inventor until many years later. Today, this steelmaking process
is known as the Kelly-Bessemer process.
Kelly proved later in life that he could manage his own affairs. He increased his fortune several times over in real estate and banking. And
although he was not honored enough for his great discovery during his lifetime, he stand as one of those men whose contribution helped
to make America great. His process of steel-making has, to a large extent, been superseded by other methods. But for almost a century
the great advances that were made possible by the widespread use of steel could be credited to the work of Bessemer in England and
Kelly in America.