Death ray

The death ray or death beam was a theoretical particle beam or electromagnetic weapon of the 1920s through the 1930s that was claimed to have been invented independently by Guglielmo Marconi,Nikola Tesla, Harry Grindell Matthews, Edwin R. Scott, and Graichen, as well as others. In 1957, the National Inventors Council was still issuing lists of needed military inventions that included a death ray.

While based in fiction, research into energy-based weapons inspired by past speculation has contributed to real-life weapons in use by modern militaries sometimes called a sort of "death ray", such as the United States Navy and its Laser Weapon System (LaWS) deployed in mid-2014. Such armaments are technically known as directed-energy weapons.

In the year 1923, Edwin R. Scott, an inventor from San Francisco, claimed he was the first to develop a death ray that would destroy human life and bring down planes at a distance. He was born in Detroit, and he claimed he worked for nine years as a student and protégé of Charles P. Steinmetz.Harry Grindell-Matthews tried to sell what he reported to be a death ray to the British Air Ministry in 1924. He was never able to show a functioning model or demonstrate it to the military.

Nikola Tesla claimed to have invented a "death beam" which he called teleforce in the 1930s and continued the claims up until his death. Tesla explained that "this invention of mine does not contemplate the use of any so-called 'death rays'. Rays are not applicable because they cannot be produced in requisite quantities and diminish rapidly in intensity with distance. All the energy of New York City (approximately two million horsepower) transformed into rays and projected twenty miles, could not kill a human being, because, according to a well known law of physics, it would disperse to such an extent as to be ineffectual. My apparatus projects particles which may be relatively large or of microscopic dimensions, enabling us to convey to a small area at a great distance trillions of times more energy than is possible with rays of any kind. Many thousands of horsepower can thus be transmitted by a stream thinner than a hair, so that nothing can resist."

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