Nikola Tesla's 1891 Lecture to the American Institute of Electrical Engineers

Shortly before Nikola Tesla became a US Citizen in 1891, he delivered a lecture, "Experiments with Alternate Currents of Very High Frequency and Their Application to Methods of Artificial Illumination" before the American Institute of Electrical Engineers (now the IEEE) at Columbia University in New York.

Following is one of the accounts of this lecture found in the newspaper archives.

The Daily Nevada State Journal, Reno, Nevada, Tuesday, June 30, 1891, Page 2.

ELECTRICAL DEVELOPMENTS.
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For the entertainment of the American Institute of Electrical Engineers at Columbia College, New York, Nikola Tesla illustrated a lecture with a series of experiments which surprised and enlightened his audience. The New York Recorder says Tesla, who has a high reputation as an electrician, has been experimenting upon a practically new electric light, but it was not known outside his laboratory that he had achieved such wonderful results or came so near revolutionizing the theory of light. He demonstrated by experiments that incandescent lamps do not require two or three single wires to feed them, but that a single wire from a dynamo with a single branch to each lamp will answer the purpose equally well. He also does away with the carbon filament which furnishes the light in the incandescent lamps, and substitutes a solid block of carbon. The branch wire terminates in this block and causes a glow just as the continuous circuit does in the slender carbon filament now in use. This carbon filament is the most serious objection to the present form of incandescent lamps. It must necessarily be very slender to offer the required resistance to the passage of the current, and being carbon is also unavoidably of fragile substance, hence the filaments are constantly breaking, and each destroys a lamp, of which the estimated manufacture is 50,000 a day. The carbon blocks which Tesla purposes substituting for the lamps are made at little cost and can be depended upon to perform their work as reliably as a gas burner.

Image: Wireless transmission of power and energy demonstration during his Nikola Tesla's lecture of 1891.

Tesla demonstrated that electric light is possible without any lamp whatever. This was done by connecting two large sheets of zinc to the terminal of the circuit, the sheets being about fifteen feet apart. The plates served for condensers and received the charge of electricity from the wires. Between these zinc sheets a glass tube was introduced, from which the air had been exhausted. When this tube was placed between the sheets, although it was entirely disconnected and several feet distant from each sheet, it gave out a brilliant glow sufficient to light a room. The tube was moved about freely, but continued to glow as long as it remained in the electric field.

One of the most remarkable demonstrations made by Tesla was that showing the absolute harmlessness of his electric current. It was generated primarily from an alternating current dynamo, each as has so often been condemned as the essense (sic) of deadliness. This dynamo was speeded to its capacity, and by auxiliary aid the current was raised to 250,000 volts, which, under ordinary circumstances, would be 250 times more than sufficient to kill, yet

Tesla coolly received the entire charge in his body without any unpleasant results. To accomplish this wonderful feat he transformed the dynamo current into a static current, that is, from the active current which travels only along electrical conductors to the static current, which exists without the power of traveling. Tesla's wonderful achievements are due to his having made greater progress than other electricians in the direction of harnessing this static current and making it subservient to his will.

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