Thomas Doherty (1843-1916)
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By Sarah Creswell and Tom Flint, P.Eng.

An inventor, his diverse technical patents were applied to innovate human settlement and agricultural productivity.

Born in Lanark County, Canada West, in 1843, Thomas Doherty ventured from the rural farm on which he was born to the thriving town of Watford in 1874 to establish a foundry and machine shop known as the Watford Agricultural Implement Works (WAIW). His fast-growing company would lead Doherty to expand his business dealings to other regions of the province, such as Stratford and Sarnia. His business style was unique compared to others of the same time, and he demanded efficiency in order to keep manufacturing costs down to pass savings on to customers.

Although he maintained interest and involvement in the business, political and social communities until his death in 1916, Doherty was best known as an inventor. In 1881, he was granted a patent for an improvement made to a threshing machine, and in 1892, he was granted a U.S. patent for a hot water apparatus that was essentially a hot water boiler. For the latter product, he was awarded a Gold Medal and the title of “honorary member” by the Parisian Inventors Academy. Perhaps his most well-known invention, however, was a process to produce a form of iron greatly superior to cast iron, because it was steel-like in strength, but much cheaper to manufacture and much softer and more malleable to work with. Patented in 1895, the success of the “Decarbon Steel” process presented Doherty with numerous business opportunities and great wealth, as well as recognition by the American Society of Iron Founders. Doherty also worked on the invention of the automobile, acquiring some success in creating vehicles, some powered by a gas-fed engine of his own design.


Thomas Doherty was born in Lanark County, Canada West, in 1843. He was the youngest child of James and Rachel (Garrett) Doherty. The sudden death of his father in 1857 ended his formal education. By 1863, he was the only one left on the farm. William moved to the U.S.A., and Annie married Archibald Dewars in 1861 and settled near Petrolia to raise her family. In 1862, his mother Rachel remarried to Simpson Shepard, a local merchant and politician. In 1864, Doherty married Elizabeth Brown from Scotland. He spent the next few years raising a family and running the farm. But he was not destined to spend his life on the land because of his mechanical aptitude, which he developed early on. For a time, he operated a small repair shop on the farm, repairing a variety of machinery and gaining valuable experience in foundry methods. Also, working as a thresherman for 10 years, he acquired intimate knowledge of machinery’s working parts. It is believed he designed and built his own thresher in the shop. In late 1874, he learned that Watford was offering free building sites to anyone who would establish a foundry and machine shop. The following year, the family moved to Watford to establish a business.

Watford Agricultural Implement Works (WAIW)

Watford was a thriving town when Doherty arrived. The village was home to a variety of independent enterprises. With a skilled labour pool to draw on and $10,000 invested, Doherty established a foundry and machine shop known as WAIW. By 1880, there were 10 employees and several apprentices, producing a full line of implements, including threshing machines, reapers, land rollers, plows, cultivators and stump lifters. Farmers could view the product line at fall fairs in London, Watford, Arkona and Forest. A year later, WAIW had produced 100 reapers and mowers, 12 steam threshers and 10 hay rakes, which was twice the amount produced the previous year. To keep up with the demand, the foundry began operating day and night. In 1882, David Thom joined as partner, bringing not only capital, but also a wealth of experience, which he obtained while working as a foreman at
A. Harris and Son of Brantford. Doherty’s practical knowledge and experience together with Thom’s inventive genius formed a strong combination.

On delivery day, farmers brought teams and wagons into the town to pick up the rakes, reapers, binders and mowers that they had ordered. After they had finished loading, the wagons lined up to get their picture taken. Then, a procession led by the Arkona Brass Band would proudly make its way down the streets, ending with dinner at the local hotel–all this compliments of Thom and Doherty. In December of 1882, they purchased a plant in Stratford and moved the equipment to Sarnia to manufacture the Doherty steel Prairie plow. Doherty continued as managing director of Thom and Doherty until 1888, when the partnership dissolved. In 1903, WAIW was purchased by Paris Plow Company.

The Doherty Manufacturing Company, Sarnia

In October 1882, the New Doherty-Barton foundry made its first shipment of stoves to a Chatham firm. If David Thom, Doherty’s partner in Watford, was known for innovation to the implement world, Barton was equally qualified in his field. He was previously associated with McClary’s Stoveworks, London, Ontario. It is not known how long Barton was associated, but by the early 1890s, Doherty was the sole proprietor, and he renamed the business Doherty Manufacturing Company.

Doherty’s policy was to “honestly construct his products using only the best material and skilled mechanics available.” Doherty’s was the only manufacturer not employing door-to-door salespeople, thus they were able to pass the savings on to their customers. Doherty developed a process to increase the quality of cast iron, making it similar to steel, but cheaper to make. The firm called it “Decarbon Steel.” Stoves would not crack or warp and would thus outlast two other regular stoves. Therefore, the company guaranteed every stove made. After the 1913 expansion, there were 50 skilled tradesmen employed with a capacity to turn out 3000 stoves and heaters per year. After Doherty’s death in 1916, the company continued to operate, later specializing in manufacturing industrial castings.

Inventions and Innovations

When Doherty took over the family farm, few would have guessed that he would be recognized as Lambton County’s industrial pioneer. In whatever field he worked, customers would benefit because of his unique combination of technical skills, engineering ability and business acumen.

Improvement in Threshing Machines

Doherty was granted his first patent for improving the threshing machine on March 10, 1881. It was the culmination of the years spent farming and tinkering with threshing machines. The point of superiority of his machine was the perfect separation of the grains from the straw by means of improved mechanical movements. Later that year, Doherty authorized an eastern manufacturer to make his patented thresher, selling them both a machine and the set of patterns.

Hot Water Boiler

In 1892, Doherty was granted a U.S. patent for a “hot water apparatus.” The Parisian Inventors Academy awarded him a Gold medal/diploma and conferred on him the title of “honorary member.” In the early 1900s, to respond to the rise in popularity of central heating, Doherty designed, patented and manufactured a new hot water boiler.

Decarbon Steel

Doherty was best known for processing this special material. It was a form of iron greatly superior to ordinary cast iron in that it was almost steel-like in strength, yet softer and more malleable. The process, patented in 1895, involved shooting a jet of superheated steam and air into the melting furnace (cupola), which burned off a large portion of impurities and carbon usually found in cast iron. In partnership with the group of Hamilton Industries, the Doherty Process Company was formed to market the process. The European rights were sold for $500,000. In recognition of his achievement, Doherty was invited by the President of the American Society of Iron Founders to present a paper in Philadelphia on “Science in the Foundry.” The process allowed the company to expand its markets. For example, the Canadian Pacific Railway ordered 200 sets of axle box covers (formerly made of brass).


His first effort was a three-wheeled vehicle with a tiller steering powered by a huge coil spring that could travel at 2 to 3 miles per hour for a few blocks. Disappointed with the limitations, Doherty began to work on a gas-powered vehicle in early 1900. The autobicycle, built mostly from bicycle parts, was completed and road-tested the same year. The red two-seater soon became reputable for speed and handiness. Not everyone was impressed with this new mode of transportation. In August 1902, Doherty was banned from Sarnia to Florence Plank Road, because horses were startled by the sound of the noisy engine, upsetting the rigs. The ban was later upheld when a judge ruled “that the evidence clearly showed the automobile to be dangerous and a nuisance.”


The gas-powered engine that powered Doherty’s autobicycle was of his own design. It featured two pistons in one cylinder, which fired in opposite directions at the same time. It was patented in 1902. The engine was manufactured in Sarnia for the Canadian market and sold for $200. Later, Doherty designed and manufactured a single-piston auto and marine engine.

Community Service and Politics

Doherty maintained a keen interest in the community, strongly believing in public service and making it an integral part of his life. In 1880, during agricultural expansion, he served the citizens on Watford town council. When he moved to Sarnia in 1882, he served as a private citizen before he was officially elected. In 1895, Doherty was elected as one of the first trustees of the Sarnia Street Railway and went to Philadelphia to investigate the purchase of electric motors for the horse car line. As an early president of Sarnia’s Board of Trade (forerunner of the Chamber of Commerce), he worked closely with the industrial committee of the town council. He was elected to head the Industrial Club of Sarnia when it was formed in 1907. It was established to promote Sarnia’s interests and to attract new industry.

As the owner of the first automobile in Sarnia, he was the ideal choice to head the Sarnia Automobile Club, whose main aim was to work with the police for the safety of pedestrians, and to regulate traffic. In the early 1900s, one of his main interests was securing a safe supply of water for Sarnia, which had been plagued by typhoid fever outbreaks. In 1916, he was acclaimed mayor, mainly because he pledged to solve the difficulties at the new pumping station. The eventual solution came largely due to his advice and suggestions. While in office, Doherty sought to find employment for soldiers returning from the front who were medically unfit for further service. He died on September 7, 1916 at the age of 73, shortly after concluding his address at the cornerstone-laying ceremony for an addition to the Sunday School of St. Paul’s Presbyterian Church.

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