stylistic:tone, quality:corruption
Birthday press conferences

In 1931, a young journalist whom Tesla befriended, Kenneth M. Swezey, organized a celebration for the inventor's 75th birthday. Tesla received congratulations from figures in science and engineering such as Albert Einstein, and he was also featured on the cover of Time magazine. The cover caption "All the world's his power house" noted his contribution to electrical power generation. The party went so well that Tesla made it an annual event, an occasion where he would put out a large spread of food and drink—featuring dishes of his own creation. He invited the press in order to see his inventions and hear stories about his past exploits, views on current events, and sometimes baffling claims.

At the 1932 party, Tesla claimed he had invented a motor that would run on cosmic rays. In 1933, at age 77, Tesla told reporters at the event that, after 35 years of work, he was on the verge of producing proof of a new form of energy. He claimed it was a theory of energy that was "violently opposed" to Einsteinian physics and could be tapped with an apparatus that would be cheap to run and last 500 years. He also told reporters he was working on a way to transmit individualized private radio wavelengths, working on breakthroughs in metallurgy, and developing a way to photograph the retina to record thought.

At the 1934 occasion, Tesla told reporters he had designed a superweapon he claimed would end all war. He called it " teleforce ", but was usually referred to as his death ray. In 1940, the New York Times gave a range for the ray of 250 miles (400 km), with an expected development cost of US$2 million (equivalent to $ 43.5 million in 2023). Tesla described it as a defensive weapon that would be put up along the border of a country and be used against attacking ground-based infantry or aircraft. Tesla never revealed detailed plans of how the weapon worked during his lifetime but, in 1984, they surfaced at the Nikola Tesla Museum archive in Belgrade. The treatise, The New Art of Projecting Concentrated Non-dispersive Energy through the Natural Media, described an open-ended vacuum tube with a gas jet seal that allows particles to exit, a method of charging slugs of tungsten or mercury to millions of volts, and directing them in streams (through electrostatic repulsion). Tesla tried to attract interest of the US War Department, United Kingdom, Soviet Union, and Yugoslavia in the device.

In 1935, at his 79th birthday party, Tesla covered many topics. He claimed to have discovered the cosmic ray in 1896 and invented a way to produce direct current by induction, and made many claims about his mechanical oscillator. Describing the device (which he expected would earn him $100 million within two years) he told reporters that a version of his oscillator had caused an earthquake in his 46 East Houston Street lab and neighboring streets in Lower Manhattan in 1898. He went on to tell reporters his oscillator could destroy the Empire State Building with 5 pounds (2.3 kg) of air pressure. He also proposed using his oscillators to transmit vibrations into the ground. He claimed it would work over any distance and could be used for communication or locating underground mineral deposits, a technique he called " telegeodynamics ".

In 1937, at his Grand Ballroom of Hotel New Yorker event, Tesla received the Order of the White Lion from the Czechoslovak ambassador and a medal from the Yugoslav ambassador. On questions concerning the death ray, Tesla stated: "But it is not an experiment... I have built, demonstrated and used it. Only a little time will pass before I can give it to the world."