The Engineer

Aug 11, 2023

Nineteenth century American inventor Charles Goodyear survived decades of hardship while developing his vulcanization process to make rubber a viable industrial material. Written by Nick Smith.

Serendipity has played a part in many of the greatest engineering breakthroughs: Velcro, Teflon, Kevlar, even dynamite. But there has been perhaps no more serendipitous event in the development of industrial materials than when, in 1839, Charles Goodyear accidentally dropped a piece of sulphur-coated rubber onto a hot stove, causing it to char and metamorphose into a leather-like substance. In one moment, the American inventor had uncovered the secret to stabilising the sticky, unreliable and unmanageable latex from the rubber tree Hevea brasiliensis that had struggled to fulfil its long-observed potential.

Even though it could be argued that the Mesoamericans had discovered vulcanization more than three millennia ahead of Goodyear, it was the self-taught manufacturing engineer from New Haven, Connecticut whose name would appear at the top of the United Stated Patent Office document (No. 3633) outlining a process for the ‘Improvement in India-Rubber Fabrics’ that would be named after the Roman god of fire. ‘I hereby declare’ wrote Goodyear that ‘my principal improvement consists in the combining of sulphur and white lead with the India-rubber, and with the submitting of the compound thus formed to the action of heat at a regulated temperature’ As noted in Who Made America? over the following decades vulcanized rubber ‘was to be used to manufacture shoes, waterproof clothing, life jackets, balls, hats, umbrellas, rafts... and one day, it would be an important component in tires, roofs, floors, transmission belts, assembly lines, shock absorbers, seals and gaskets.’ By the close of the 20th century, Goodyear’s name was most associated with a typographical logo emblazoned on tyres supplied to the Formula One motor racing franchise.

Charles Goodyear was born in the last days of the 19th century on 29 December 1800 in the state of New York. Descended from one of the founders of the colony of New Haven, his ancestor Stephen Goodyear was head of the London Merchants company. Goodyear followed in the family’s mercantile tradition by working as a partner in his father’s hardware business, where he was involved in the manufacture of ivory and metal buttons, as well as agricultural tools. During the 1830s the financial panic – created by the tightening of credit and the prohibition of trade between the US and English colonies – caused the enterprise to collapse, prompting Goodyear’s investigation into the properties of rubber. According to the Goodyear corporate website: ‘Others had used it for rubber shoes and coats, but they melted during the heat of summer. Goodyear believed rubber could be “tanned” or “cured” like animal hides. Dropping all other interests, Goodyear tried adding various chemicals to change rubber’s properties, commandeering his wife’s kitchen in the process.’

Life should not be estimated exclusively by the standard of dollars and cents.

Charles Goodyear (1800 - 1860)

Meanwhile Goodyear’s research into natural rubber had led him to New York, where he saw inflation tubes for life jackets made from the substance. Realising they were defective – with thousands of dollars’ worth of products returned to their manufacturers every year – he designed his own tubes that he presented to the manager of the Roxbury Rubber Company, who saw Goodyear’s innovation as a lifeboat for his organisation that was suffering economically. The hot summer had melted Roxbury’s inventory into ‘a reeking, worthless paste,’ leaving the firm’s management, that had heavily invested in lengthy testing and experimentation, starting to regret ever becoming involved with rubber.

Goodyear, who was by then obsessed with rubber, was not discouraged. Neither was he discouraged when, as one biographer puts it ‘having made progress but no money’, he was thrown into a debtor’s prison. Wherever he landed, he continued to experiment by adding chemicals (such as magnesia) to reduce the adhesiveness of India rubber and lessen its susceptibility to extremes of temperature. As his experiments failed so did his finances, and having sold his furniture Goodyear resorted to living in a rented attic in New York. His biographer Charles Slack notes in Noble Obsession, the ‘single-minded genius’ even sold his children’s school textbooks to finance his laborious research, although he clung on to a set of China teacups, ‘not out of sentiment but because they could double in the evenings as mixing bowls for rubber and turpentine.’ Goodyear would improvise non-stop with chemical compounds on his kitchen table before testing them at a mill in Greenwich Village three miles away, in the process inhaling the fumes of his toxic concoctions made from nitric acid, lime and turpentine. During one such experiment he almost suffocated due to gases produced in his laboratory. He recovered, but the ensuing fever nearly killed him.

According to Ann Marie Somma’s article Charles Goodyear and the Vulcanization of Rubber, this was but one of many setbacks. The inventor won a contract from the United States Post Office in Boston to make rubber mailbags only to find that they melted in hot weather. Then in 1837 his family lost everything in that year’s financial panic. ‘But his luck changed in 1839 in a factory in Woburn, Massachusetts, where Goodyear now lived to be close to the rubber factories that had sprung up in the city… While working at the Eagle India Rubber Company, Goodyear accidentally combined rubber and sulphur on a hot stove. Much to Goodyear’s surprise, the rubber didn’t melt. And when he raised the heat, it actually hardened.’

And yet ‘it would take several more years to recreate the chemical formula and perfect the process of mixing sulphur and rubber at high temperature.’ This part of Goodyear’s journey was shared by the US businessman and inventor Nathaniel Hayward, a former employee of the rubber factory at Roxbury, who had discovered that when treated with sulphur the material lost its stickiness. Goodyear bought Hayward’s 1839 patent No.1090 (that anticipated Goodyear’s by five years) for the ‘improvement of preparing caoutchouc with sulphur for the manufacture of various articles.’ In something of an understatement, the Goodyear website describes this phase of vulcanized rubber’s evolution as ‘hit and miss… but in 1841, Goodyear successfully applied the vulcanization process using heated cast iron.’

By 1842 that process was a family business with operations in a small factory in Springfield, Massachusetts, run by his brothers and his wealthy brother-in-law, known to history only as Mr de Forest. The objective of the project was to mechanise a practical method of vulcanizing rubber, which culminated in United Stated Patent Office No.3633 among others, some of which were sold to the American industrialist Hiram Hutchinson who was to found the eponymous French manufacturing company known today as a major global rubber producer and for its involvement in the aerospace and automotive sectors.

The 1850s were to be the last decade of Goodyear’s life, a time mostly dominated by a series of messy legal wrangles in which the names of other rubber pioneers such as Macintosh and Moulton were writ large. While in the employment of Charles Macintosh and Company, Thomas Hancock claimed to have independently invented vulcanization, with his British patent finalised in 1844, the same year as Goodyear’s. Slack describes the rivalry between the two as ‘bitter’, characterising Hancock as ‘a scholarly English inventor who got wind of Goodyear’s discovery and beat him to the patent office.’ Goodyear’s agent Stephen Moulton, who had introduced samples of vulcanized rubber to the UK, stepped in and became embroiled in a series of disputes with Macintosh, claiming that Hancock had copied Goodyear. Independent scientific tests were unable to settle the argument conclusively, leaving Goodyear to face a seemingly never-ending litany of patent infringements.

Goodyear’s entry in Britannica untangles what happened next: ‘the decisive victory did not come until 1852. That year he went to England, where articles made under his patents had been displayed at the International Exhibition of 1851; while there he unsuccessfully attempted to establish factories. He also lost his patent rights there and in France because of technical and legal problems… in December 1855 Goodyear was imprisoned for debt in Paris. Meanwhile, in the United States, his patents continued to be infringed upon.’

Despite the difficulty in estimating the colossal fortunes made from his invention, Goodyear – who during the 1850s also found time to write a book called Gum-Elastic and Its Varieties – died owing $200,000 (more than $7m in today’s money). And while lesser mortals might have seen this as a personal insult, the inventor that had endured ‘poverty, ridicule, life-threatening illnesses, jail, and self-torment’ could not find it in himself to complain that ‘others have gathered the fruits’ of what he had planted, preferring to reflect that ‘life should not be estimated exclusively by the standard of dollars and cents, as is too often done. Man has just cause for regret when he sows and no one reaps.’