Henry Bessemer was a Victorian engineer who made
important discoveries in the production of steel, and who therefore laid the
foundation for much of Great Britain’s later success in industry and
manufacturing.
He was born on 19th January 1813 at
Charlton, a village near Hitchin in Hertfordshire. His father Anthony had been
trained in engineering and operated a typefounding business.
Henry only had an elementary education and spent
much of his childhood watching his father at work and carrying out experiments
of his own. When he was 17 his father moved his business to London and Henry
found himself in the capital with no trade or profession but an inventive turn
of mind that he hoped to put to productive use.
He carried out a range of experiments in several
fields, including electroplating and the development of a machine for sugar
refining.
In 1833 he developed a die stamp that could be used
on official documents to prevent fraud. The idea was that the stamp perforated
the document with hundreds of tiny holes, thus making the document virtually
impossible to counterfeit. Although this invention was enthusiastically taken
up by the Government Stamp Office, Bessemer was never rewarded for it.
He had more success with his development of bronze
powder which was used to give the appearance of gold in the decoration of
various objects. He devised a manufacturing process that was much more
efficient than what had previously been available, and set up a workshop for
its production. This venture was highly successful and gave him the funds he
needed for his later work, such that he was never dependent on bank loans to
pay for the many patents that he would register during his career.
He was also able to buy a house in Highgate and an
office in the City of London, as well as maintaining his factory. In April 1834
he got married, his wife Ann being the daughter of a friend.
The Bessemer Converter
The Crimean War turned Bessemer’s attention to the
work for which he is best known, namely a way of producing a metal that was
strong enough to withstand the forces involved in artillery weapons. He had
already developed the idea of a revolving shot, which could be fired with
greater accuracy, but existing gun barrels were too weak to take the pressure.
Bessemer’s solution was to blow air through molten
iron within an egg-shaped furnace – the “Bessemer Converter”. This had the
effect of reducing the carbon content and creating mild steel that was far
stronger than wrought iron and was also cheap to produce.
Bessemer clearly felt that he had solved all the
problems involved in steel production and he delivered a paper (entitled “On
the Manufacture of Iron and Steel without Fuel”) at a meeting of the British
Association for the Advancement of Science in August 1856, confident that his
fortune was made and that other manufacturers would also grow rich from using
his method.
However, problems soon arose due to Bessemer’s lack
of basic metallurgical knowledge. He had failed to appreciate that not all
samples of wrought iron would react in the same way to his conversion process,
due to their chemical composition. For example, a high phosphorous content led
to steel that was brittle at low temperatures.
Improvements to the conversion process were made
thanks to the work of Robert Mushet, who suggested the use of a compound of
iron, carbon and manganese to prevent over-oxidation, and a Swede, Göran
Göransson, who redesigned the airflow system of the converter. After these
refinements were made it became possible to manufacture high-grade steel
reliably and in bulk.
The Bessemer Steel Works
In 1858 Henry Bessemer opened the Bessemer Steel
Works in Sheffield, together with three partners. Other Sheffield steelmakers
came to appreciate the value of the Bessemer process and applied for licences
to adopt it in their own factories.
Steel production now increased by leaps and bounds.
By 1870 some 200,000 tons of Bessemer steel were being produced annually by fifteen
Sheffield companies. However, by 1880 the tonnage had increased to one million
and by 1890 to two million, this being two-thirds of all steel production in
the United Kingdom. Much of this steel was used in the rapidly growing railway
system and in shipbuilding, with large quantities being exported for use in
Britain’s overseas colonies.
The Bessemer process also proved highly popular in
the United States, where production reached six million tons a year by 1900.
One black mark against Henry Bessemer was his
reluctance to acknowledge his debts to fellow inventors, particularly Robert
Mushet and Göran Göransson. He granted Mushet a small pension for his
contribution, but only after personal pleas from Mushet’s daughter and friends,
and his autobiography (published posthumously in 1905) never mentioned Göransson
at all. Bessemer was the sort of man who was happy to claim credit for all the
success that came his way but to overlook his mistakes, of which there many
throughout his career.
Bessemer was knighted in 1879, having retired from
active business in 1873. He died at his London home in 1898 at the age of 85.
His wife had died the previous year, and he was survived by two sons and a
daughter.
© John Welford
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