If asked to state who invented the
pneumatic vehicle tyre, most people would answer that the honour belongs to the
Scottish veterinary surgeon John Dunlop, whose invention in 1888 of a reliable
rubber tyre for bicycles was certainly a very significant step on the way to
the modern tyre.
However, the concept of pumping air inside
a tube surrounding a wheel, with a view to absorbing most of the bumps and
producing a smoother ride, goes back to 1845 and the Scottish civil engineer
Robert William Thomson (1822-73).
Thomson had his own workshop from the age
of 17 and later became a civil engineer on the burgeoning railway system. One
of his most useful inventions in this capacity was a method for firing
explosive charges remotely by using electricity, which no doubt saved many
lives as tunnels and cuttings were blasted out of solid rock.
He was only 23 when he thought up the idea
of the pneumatic tyre, which he termed the “aerial wheel”. It consisted of an
air-filled tube of natural rubber encased in leather which in turn was fixed to
the wheel of a carriage. He patented his invention in France in 1846 and the
United States in 1847, and it proved to be a reasonable success. However, the
leather coverings did not prove to be very durable, and Thomson did not proceed
with further developments.
Instead, Thomson turned his attention to
the possibilities offered by a new form of rubber, namely vulcanized rubber,
that was tougher and more resilient to changes in temperature. The process had
been invented in 1839 by Charles Goodyear, and it involved heat-treating rubber
to which sulphur had been added. However, Thomson abandoned the concept of
air-filled tubes and concentrated on developing carriage wheels shod with solid
rubber tyres.
It was therefore left to John Dunlop to
combine the use of air-filled tubes and vulcanized rubber covers to produce the
sort of tyre that is familiar to us today. Dunlop’s work was extremely timely,
given the important improvements in bicycle design in the 1870s and 1880s. The
combination of the “safety” bicycle and Dunlop’s tyres led to a massive boost
in popularity of the bicycle, which was to become a “must have” for people
across the social classes.
However, Robert Thomson had the last laugh,
because Dunlop was told in 1890 that Thomson’s earlier patents invalidated his
own of 1888.
© John Welford