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Then Again: Fame eluded Brandon man who invented the electric motor – vtdigger.org


In 1837, Thomas Davenport of Brandon received the world’s first patent for an electric motor. It was, in fact, the first patent for any sort of electrical device. His wife, Emily Goss Davenport, suggested the use of mercury as a conductor, and tore up her wedding dress to use as insulation. Wikimedia Commons

Thomas Davenport helped create the modern world, but has largely been forgotten by it. 

He invented a device that makes possible so many of the trappings of life today: refrigerators and freezers, washing machines and dryers, dishwashers and microwave ovens, air conditioners, hair dryers, electric fans, electric clocks, lathes, forklifts, elevators, garage door openers, subway cars, satellites, electric vehicles — the list goes on. Even the computer, tablet or phone you are reading this on. 

But any dreams Davenport harbored of attaining wealth and renown were thwarted by an absurd amount of poor timing, bad luck and disastrous decisions. 

His biggest misfortune was that his invention was half a century ahead of its time. 

Davenport’s biography contains two seemingly incompatible facts: He was a poorly educated blacksmith from the hinterlands of Vermont, and he invented the first electric motor ever patented. That he did so nearly 200 years ago shakes our image of what life was like during the early decades of the 1800s.

“He had a vision of an electrified future,” says Dave Hammond, a scientific electronics technician in the University of Vermont’s physics department. Hammond has been immersing himself in the life and work of Davenport lately, even building models of his motors.

Click here to see a video of Hammond’s motors in action.

Dave Hammond, of the University of Vermont’s physics department, reproduced three working models of Davenport’s electric motor. Photo courtesy of Dave Hammond

Some of Davenport’s motors still exist — notably at the Smithsonian Institution. Hammond constructed three copies of the motor — one for UVM, one for the Brandon Museum (in the Vermont town where Davenport invented his device), and one for Beta Technologies of Burlington, an aerospace manufacturer developing vertical takeoff and landing aircraft powered by cutting-edge electric motors.

The working model will be on display in Brandon at the inaugural Davenport Electric Fest from 11 a.m. to 6 p.m. on Saturday, July 9, which is the 220th anniversary of the inventor’s birth. The event will also feature hands-on exhibits of various electric vehicles, including electric cards, e-bikes and snowmobiles.

Like Franklin and Fulton

Though he is little remembered today, Davenport drew high praise during his lifetime. One newspaper claimed his name would be remembered alongside such great inventors as Benjamin Franklin and Robert Fulton.

High praise, and much more than his parents might have expected for him when Thomas was born in 1802, the eighth of 12 children in a poor farming family in Williamstown, Vermont. He was apprenticed to a local blacksmith for seven years, starting at age 14. In exchange for Thomas’ labor, the blacksmith would teach him the trade and allow him to attend school for six weeks each winter. 

Despite his meager learning, Thomas was curious about the world, even bookish. The boy was said to read sometimes while working the forge’s bellows. After completing his apprenticeship, he was able to establish a blacksmith shop in Brandon, which had an active iron smelting industry. 

For nearly a decade, Davenport focused on his trade, but in 1832 gave up his business. He was fascinated by electricity and wanted to study it. He was hardly alone in this fixation; some of the brightest minds in natural philosophy, what we would call science, were trying to understand and harness electricity’s power. 

“Electricity was a really mysterious thing to people at these times,” explains Hammond. “They called electricity a fluid, since that was what was familiar to them.”

People were, however, familiar with static electricity. To earn money, Davenport visited local schools to teach about electricity. Accompanying him was fellow Brandon resident Johnny Johnson, who brought along a tame moose pulling a cage full of animals. This was part science exhibit, part carnival show.

“Davenport would put a silver dollar in the bottom of a bucket of water and tell the children they could have it if they could grab it,” Hammond says. Davenport was in no danger of losing the valuable coin, because the bucket was hooked to a static electricity generator. Anyone trying to snag the dollar got a shock instead. 

The following year, 1833, Davenport had an epiphany that changed his life. He learned that an iron works in Crown Point, New York, was using electromagnets built by Joseph Henry of Albany (future first secretary of the Smithsonian Institution) to pull bits of iron from the rocks extracted there. The magnets were supposedly so strong they could suspend an anvil. 

Davenport traveled more than 25 miles by horse to the site to see the magnets and perhaps purchase one, but discovered that the owner was away. Undaunted, Davenport eventually managed to purchase one of Henry’s electromagnets, though at great expense.

Back in Brandon, Davenport took apart the magnet while his wife, Emily, took detailed notes on how it was constructed. Davenport noticed that the magnet was insulated with silk, and assumed he needed to use silk too, though other materials would also have worked. Silk was hard to come by in rural Vermont, so Emily sacrificed her wedding dress, cutting it into strips that furnished Thomas with all the insulation he needed for years. 

Davenport created a second magnet and used it to test a theory. He believed electricity could cause a machine to move. After attaching one magnet to a wheel and a second magnet to the stationary frame that held the wheel, he wired each magnet to a battery. The wheel turned. Though it rotated only half a revolution, the wheel’s movement was revolutionary. 

Of course, a half-turn doesn’t get you very far, but Davenport knew he was on to something. He found that, if he reversed the wires to the magnets, the wheel would complete the revolution. His original motor revolved only about one to three times per minute. 

He continued to tinker, and with the assistance of his neighbor, a skilled mechanic with the odd name of Orange Smalley, Davenport added magnets to the system and developed a way to reverse their polarity automatically. By the summer of 1834, they had created a motor that could turn 30 times a minute. 

Davenport understood the power he was tapping into.

“Like a flash of lightning,” he later wrote, “the thought occurred to me that here was an available power within the reach of man.”

The early 1800s were the age of steam. People used the forces unleashed by boiling water to power industry and transportation, in the form of steamboats and trains. But Davenport saw a major drawback with steam. Under too much pressure, steam would cause boilers to explode, with dramatic and often fatal effect. Davenport sought a safer source of power.

People derided Davenport for his claims. Some said he was boasting of having invented a perpetual motion machine. Others said his machines’ output should be measured not in horsepower but in mosquito power. But Davenport confronted more severe obstacles than mere mockery.

“Everybody, regardless of when they made a motor and how they made a motor, faced the same problem: Where do you get the power for this thing?” Hammond explains. 

The financing problem

Davenport’s electric motor relied on battery power, which was expensive, though he was confident the price would drop over time. However, Hammond says, “Until the dynamo was invented and perfected in the 1860s, there was no way to generate electricity reliably.”

Davenport needed allies to advance his cause. If his device was going to change the world, he needed money. Elite scientists of the day disdained conducting research for money. They believed it should be done solely to advance knowledge. Davenport didn’t have the luxury to share that opinion. 

A sketch accompanying Thomas Davenport’s 1837 patent for an electric motor.

He found a strong advocate in the scientific community when he demonstrated his device to Edward Turner, a Middlebury professor of natural philosophy, in fact the only one teaching science at the school at the time. Turner grasped the revolutionary nature of Davenport’s motor and urged him to secure a U.S. patent, even drafting wording for a patent application.

In 1835, Davenport made the arduous journey to Washington, D.C., to apply in person, stopping en route to visit eminent men of science and demonstrate his motor. When he arrived, he discovered that the cost of a patent application, which included hiring a draftsman to sketch his machine as well as other expenses, was more than he had left in his pocket. He didn’t even have enough money to return home. 

He could, however, make it as far as Troy, New York. There he called on Stephen van Rensselaer, founder of an esteemed polytechnical school. And was immediately set upon by the man’s dogs. While a kitchen maid mended his clothes, Davenport showed Rensselaer his motor. Rensselaer bought the device for his institute, so Davenport had enough money to get home.

He returned to Washington the next year to submit his patent application, complete with a working model. That December, a fire at the U.S. Patent Office destroyed both his model and paperwork. He returned in January 1837 to apply yet again. 

then-again-thomas-davenport
Middlebury professor Edward Turner was enthusiastic about Thomas Davenport’s electric motor and suggested he patent it. Turner even drafted a description of the machine Davenport could use in his patent application. The motor for which Davenport eventually won a patent was a modified version of the one he showed Turner. Above is a copy of Turner’s draft, which appeared in an 1891 edition of the journal The Electrical Engineer.

The third time did the trick. In February he received his patent. “It was the first electrical patent ever granted,” Hammond says, “and probably the broadest patent ever issued.” He notes that the patent granted Davenport the exclusive right to “the idea of electromagnetically moving anything.” 

The Patent Act of 1836 gave Davenport that sole right for 21 years. He had plenty of time to make a fortune. If things hadn’t gone terribly wrong.

Money would pour in

By this point, Davenport had another partner, Ransom Cook, who ran a successful cabinetmaking business in Saratoga, New York, and shared an interest in the new science of electricity. Cook’s design expertise and skilled workmen helped improve the motor. 

The two men met when Davenport was touring with his motor, charging admission for the privilege of watching it spin. Many audience members viewed the device as a novelty, but Cook saw the practicality of it. 

Now that Davenport held a patent, he could get strangers, not just friends and neighbors, to invest in his motor. The men set up a business in Manhattan to search for investors. Edwin Williams, the head of an organization that promoted invention, approached them about launching a joint-stock company, the precursor of the modern corporation. Williams’ lawyer would draw up the papers.

The arrangement would let Davenport and Cook focus on improving the motor, while money poured in to support the venture. The prospectus for their stock offering quoted enthusiastic praise from New York City newspapers. “(A)n electromagnetic engine, constructed on this principle, will cost only one-tenth the expense of steam power, and only occupy one half of the space,” the New York Herald declared. “There can be no doubt, in our mind, but the days of steam power, and animal power, and water power, are gone for ever.”

The New York Evening Post predicted that “The application of this new principle of motion … is one of the most wonderful inventions of the age, and will hand down the name of its discoverer to future times along with those of Franklin and Fulton.”

The Baltimore Daily Gazette estimated that the patent rights in America alone would be worth the astronomical sum of $600,000. Davenport had also secured a patent in Britain, which was far ahead of the United States in terms of industrialization. 

The Daily Gazette’s estimate was wide of the mark. If there was a time to start a new company, 1837 wasn’t it. A financial panic gripped the country and few investors found an electric motor company irresistible. Whatever money came in, little reached Davenport and Cook. The men took Williams to court, but failed to gain satisfaction.

If no one else believed in his invention, Davenport didn’t lose faith. He demonstrated that it could be used to power a drill to bore holes in iron and steel, and to power a printing press. Fittingly, the press printed America’s first electrical journal, “The Electro-Magnet and Mechanics’ Intelligencer.”

In early 1842, Davenport seemed to catch a break. An investor gave him $3,000 in notes, drawn on an Ohio bank, to support his work. Davenport cashed a $10 note, with plans to draw the rest later, but typical of Davenport’s luck, the bank folded before he could cash any more.   

By the fall of 1842, Davenport had had enough. He moved with his family back to Brandon, where he died nine years later, never having realized his dream of seeing electric motors supersede steam power. 

The electric motor was, of course, an invention whose time would come. Davenport just had the great misfortunate of understanding its potential long before its time.