John Boyd Dunlop

Scottish veterinarian

• Born: February 5, 1840
• Birthplace: Dreghorn, Ayrshire, Scotland
• Died: October 23, 1921
• Place of death: Dublin, Ireland

Dunlop developed many aspects of the pneumatic tire at exactly the right historical moment: Cycling was in its infancy, and the age of the motorcar was just around the corner. His inventions ensured the success, safety, and popularity of bicycles, automobiles, and other vehicles.

Primary field: Automotive technology

Primary invention: Pneumatic rubber tire

Early Life

John Boyd Dunlop (DUHN-lop) was born into a farming family on February 5, 1840, in Dreghorn, Ayrshire, Scotland, the son of John Dunlop, a tenant farmer, and his wife, Agnes (née Boyd). As a young boy, he attended the local parish school and so excelled that even at an early age the schoolmaster had him teach arithmetic to the younger pupils. At some point, however, he was told that he was born two months earlier than expected. This apparently trivial point appears to have seriously disturbed Dunlop: He believed that it must have affected his health, and for much of his life he tended to avoid travel and other exertions. Indeed, he was considered somewhat too fragile as a boy to work on the farm and had to complete his schooling in Edinburgh. Having spent much of his childhood on the family farm, he developed a love of animals that undoubtedly influenced his decision to pursue a career in veterinary medicine.

He attended the Royal (Dick) Veterinary College in Edinburgh (now part of the University of Edinburgh) and was an excellent student, completing his studies in April, 1859, at the age of nineteen. After earning his diploma, along with an honorary fellowship of the Royal Veterinary Society of Edinburgh, he worked as a veterinarian in the city for several years before moving to northern Ireland in 1867 and establishing a very successful practice in Belfast. He married Margaret Stevenson, a farmer’s daughter, in 1871, with whom he had a son, John (Johnnie), and a daughter, Jean.

Life’s Work

Dunlop became well known in Belfast as a kind man and an excellent vet, a reputation that contributed to the success and growth of his practice. Within twenty years, his was one of the largest practices in Ireland, so large that he had to employ twelve men just to shoe horses. (Veterinarians at this time were essentially horse doctors and were almost indispensable, as horses were in such widespread use for personal and commercial transportation.) Dunlop had to cover a large area in his work and would have endured many uncomfortable rides, which, for a man of a delicate constitution, would have made him only too well aware of the bumpy nature of the city’s streets.

His concern for the welfare of animals led him to attempt to ease the discomfort of horses that had to strain to haul heavy loads. The family doctor, Sir John Fagan, who was also a client of the veterinary practice, mentioned that he often attempted to improve his patients’ comfort by having them lie on air-filled cushions, an idea that Dunlop attempted to apply to horse collars. Fagan also suggested that ten-year-old Johnnie take up cycling as exercise.

The pedal bicycle had itself been invented only a few decades earlier by Kirkpatrick MacMillan in 1839, but its wheels were bare metal, giving no comfort over the jolts and vibrations of the roadways. Solid rubber tires were introduced after Charles Goodyear’s improvement of the vulcanization process (patented in 1844) that made rubber sufficiently durable for such use, but they gave only moderately better comfort. The bicycle itself underwent many developments, culminating in the invention of the “safety cycle” by John Kemp Starley in 1885. One of the most significant and fundamental changes to the bicycle, and one that would revolutionize its use, was made by Dunlop just three years later.

Johnnie complained of the jarring he experienced in riding over the bumps of Belfast’s cobbled streets, prompting his father to set himself to make cycling more enjoyable for his son. He realized that air would cushion the ride of a cyclist, just as it cushioned his horses’ collars and Fagan’s patients: He made the crucial mental leap to see that a hollow tube filled with air, attached to the rim of each wheel, would provide the means to achieve this. Dunlop’s first experiments used a solid wooden wheel, to which he attached the inflated rubber tube inside a rubberized canvas cover nailed to the wheel. By comparing the bouncing and rolling properties of this wheel with one shod in solid tires, he not surprisingly found that the cushioned tires performed better. Next, Dunlop applied his principle to the rear wheels of his son’s tricycle. He improved the construction of the covered air tubes, attached them around wooden wheel rims, and even included a primitive valve for inflation of the tire. A trial of the modified tricycle in February, 1888, conducted secretly at night, immediately established its improved comfort and speed. These successes led Dunlop to demonstrate his technology to local businessmen, and he applied for a patent for his pneumatic tires in July, 1888.

Many more tests were made, culminating in Dunlop designing and purchasing tires from a Scottish company that were fitted to locally built cycles. These were put on sale, complete with pneumatic tires. A local racing cyclist, William Hume, also ordered a machine equipped with the new tires, and when in May, 1889, Hume defeated many superior riders who raced with solid rubber tires, the future of the pneumatic tire seemed secured. Later that year, Dunlop went into business with the entrepreneur William Harvey Du Cros, whose sons had been among the riders Hume defeated, and the two men launched the Pneumatic Tyre and Booth’s Cycle Agency.

After retiring from practice in 1892, Dunlop remained active in the tire business. Du Cros, meanwhile, helped steer the company through many troubles, the principal of which was the revelation that Dunlop’s patent was invalid: His fellow Scot, Robert William Thomson, had already patented the pneumatic tire in 1846. However, Dunlop and the firm held auxiliary patents, notably for the non-return valve, wheel rims, and methods of attaching the tire to the rim. The company survived much turmoil and litigation and would ultimately become the Dunlop Rubber Company, an international group that by 1954 comprised over 130 companies manufacturing a broad range of rubber goods, sports and cycling equipment, and, of course, tires.

Dunlop lived quietly in Ballsbridge, near Dublin, in his retirement. Despite his tendency to hypochondria, he enjoyed good health all his life and lived until the age of eighty-one. He had no serious illness until late 1921 when, suddenly and unexpectedly, he died following a slight chill on October 23. Dunlop had worked on a history of the pneumatic tire over the last few years of his life; the book was published posthumously by his daughter, Jean McClintock.

Impact

Dunlop’s “reinvention” of the pneumatic tire revolutionized virtually all of land transportation. It is hard to think of riding in any road vehicle without the cushioning that tires provide. It is truly remarkable to realize that all of Dunlop’s original experiments, and the technological advances that they brought, were achieved by a man who was neither a cyclist nor an engineer, but a vet, working only with his own hands and with the relatively simple tools and materials available to him at home and at his business.

Despite having no valid patent, Dunlop managed to bring his tires to the world, and they are now as ubiquitous as the bicycle and the automobile: Modern life is almost unimaginable without them. He made little profit from his invention, yet his name is remembered through the quirk of fate that he was—historically—in the right place at the right time. Nevertheless, his unique circumstances and his critical realization of the potential applications of pneumatics justify his place in history.

Dunlop’s tires changed the world in many other unexpected ways as well. Ironically, they had a significant effect upon the veterinary profession. When the popularity of cycling and the automobile rocketed, with a corresponding drop in horse riding, “horse doctors” were forced to expand their horizons. They began treating pets and other types of animals, becoming much more like the veterinarians that are familiar today.

Bibliography

Du Cros, Sir Arthur. Wheels of Fortune: A Salute to Pioneers. London: Chapman & Hall, 1938. Detailed account of the business partnership between Dunlop and Du Cros, of the development of the pneumatic tire, and of the early fortunes of the Dunlop Rubber Company, as told by Du Cros’s son. The narrative is filled with many personal and historical particulars. Appendixes, index.

Haney, Paul. The Racing and High Performance Tire. Warrendale, Pa.: Society of Automotive Engineers, 2003. A somewhat technical, but highly informative, description of pneumatic tires and of how and why their construction and behavior relates to vehicle safety and performance. Tables, index, list of Internet resources.

Herlihy, David V. Bicycle: The History. New Haven, Conn.: Yale University Press, 2004. Extensively researched and illustrated history of the bicycle that also looks individually at the history and development of many of its components, including the tires. Bibliographic notes, index.

McMillan, James. The Dunlop Story: The Life, Death and Re-birth of a Multi-National. London: Weidenfeld and Nicolson, 1989. A retelling of the story of this company, from Dunlop’s initial experiments, to his partnership with Du Cros, and into the middle of the twentieth century. Many of the company’s innovations in tire and rubber technology are highlighted. Bibliographic notes, index.

Tompkins, Eric. The History of the Pneumatic Tyre. Suffolk, England: Eastland Press, 1981. A detailed account of the development of the pneumatic tire up to recent times, written by a retired former employee of the Dunlop company. Indexes.