The Panacea That Wasn't: The Arc of the Tesla Coil

Inventor and engineer Nikola Tesla successfully registered more than three- hundred patents in his lifetime. Although his interests varied widely, from biology to physics, it was his lifelong dream to create wireless electricity. Toward that end, he pursued the technology that we today call the "Tesla coil." Patented on April 25, 1891, the Tesla coil moved people's imaginations, reinvigorating interest in the science of electricity, which was by the 1890s no longer a novel concept. Although in time relegated to science museums and special effects departments, it seemed like a miracle to many people throughout the early 20th century.

Not least among those people was Tesla himself. Although he had created his high-voltage transformer as a means to create wireless electricity, he then used it to research ideas such as X-rays and household lighting. Taking it on the road, he used it as the centerpiece in a series of public scientific demonstrations, making himself famous in the process. Following demonstrations at his Colorado Springs laboratory, banking magnate J.P. Morgan offered to finance the development of his wireless electrical system on a large scale.

In Shoreham, New York, Tesla and Morgan built Wardenclyffe Tower, a high-voltage power station that functioned as the world's largest Tesla coil. It cost $150,000 to build in 1901, equivalent to $4.7 million in 2021. By 1906, locals were complaining about the large flashes of electric light in the night sky, and making no meaningful progress in the field of wireless electricity, the coil became known as "Tesla's folly."

The Tesla coil, meanwhile, had found another home, among quack doctors. Using the Tesla coil as a catch-all treatment, they marketed it for use on diabetes and cancer patients alike. Tesla, for his part, made claims that he had used the Tesla coil to alleviate the symptoms of his depression. However scientifically unfounded, the Tesla coil had entered the self-taught doctor's bag at the right time, just as electroshock therapy was gaining prominence in Victorian-era medicine.

Though later the namesake of a car company as well as a unit of magnetic flux density, Tesla lived mostly in obscurity following the debacle in Shoreham. He had blown through not only large amounts of J.P. Morgan's money but all of his own savings as well. In the 1920s and 1930s, he would pass from one New York hotel to the next, leaving behind bills that he could not pay. Upon his death, however, he received some notice, including a reading by Mayor Fiorello La Guardia and a funeral attended by more than two-thousand.

Today the most practical usage of the Tesla coil, which at one time seemed poised to upend the field of electrical engineering, is in igniting mercury and sodium street lamps. While many take for granted Tesla's long- running dream of wireless electricity, found commonly in consumer electronics, modern circuitry has surpassed the capabilities of the Tesla coil. From Star Trek: The Motion Picture to the Ben Franklin Science Museum, Tesla's legacy nevertheless continues, impressing audiences the way that he did and inspiring the next generation of scientists.