Center For Integrating Research and Learning

Arrow1890 - 1899


During experiments with cathode ray tubes, German physicist Wilhelm Roentgen discovered a previously unknown form of electromagnetic radiation, the x-ray, that had the ability to pass through some opaque materials (including the body’s soft tissues) that absorb visible light. The discovery made him famous, transformed the fields of physics and medicine and sparked interest in other possible forms of electromagnetic rays.

Tesla Coil

French physicist Antoine-Henri Becquerel was among those intrigued by Roentgen’s findings. Wondering whether phosphorescence (the glow emanating from certain materials after being exposed to light) might have something to do with x-rays, he began looking into the phosphorescence of various materials, including uranium salts. In his experiments, he stumbled upon natural radioactivity, which was known for a time as Becquerel rays.

This discovery opened a whole new line of inquiry that attracted a who’s who of scientists from the era, including Marie and Pierre Curie, Paul Villard and Ernest Rutherford. Before the turn of the century, Rutherford had determined that “Becquerel rays” could be broken down into what he called alpha rays (later identified as helium nuclei) and beta rays (later recognized as electrons). A third component of radioactivity (a term coined by the Curies in 1898), gamma rays, was identified soon after by Villard. These discoveries would help steer Rutherford toward a revolutionary new model for the atom that recognized the existence of a nucleus.

The applied sciences saw more drama this decade, with Nikola Tesla again playing a leading role. He had pitted his AC electricity system against Thomas Edison's DC system and won. Now Tesla found himself in another rivalry, this one with Italian-Irish electrical engineer Guglielmo Marconi. The dispute centered around “wireless telegraphy,” a means of communication that would eventually become known as the radio.


Thanks to the work of James Clerk Maxwell and Heinrich Hertz, among others, both men understood the nature of electromagnetic waves and knew they could be used to communicate over long distances. There were technical hurdles to overcome, however, including how to generate sufficiently high frequencies and voltages. Tesla solved the dilemma in 1891 when he patented the Tesla coil, which could be used to transmit and receive powerful radio signals when tuned to resonate at the same frequency.

The men raced to patent and launch the nascent technology. Marconi won the first contest when he was granted the world’s first patent for wireless telegraphy in England. A year later, he founded a company based on the invention, while Tesla filed for a patent in the U.S., granted in 1900. (This patent was revoked a few years later in favor of an application by Marconi, then ultimately restored in 1943.) Though the record remains unclear on who may have first transmitted wireless signals, both men accomplished the feat during this decade and went on to transmit signals over greater distances. Marconi did more to develop radio, however, and won a Nobel Prize for his work.

While the war of the wireless played out, a Danish physicist pursued another advance in communications. Using magnetized steel wire to record sound, Valdemar Poulsen invented in 1898 the precursor to the tape recorder, a device he called the telegraphone.

1890 - 1899


Inventor Nikola Tesla, an immigrant to the United States, is granted a patent for the Tesla coil, which would play a role in the development of lighting, radio and other technologies.


Dutch physicist Hendrik Lorentz expands and modifies James Clerk Maxwell's theory of electromagnetism to develop his own electron theory, which would in turn serve as a foundation for Albert Einstein’s theory of relativity.


The speed of cathode ray emission is measured by English physicist J.J. Thomson and is found to be significantly slower than the speed of light.


French physicist Pierre Curie defends his thesis on magnetism, which includes his experimental findings regarding the effect of temperature on paramagnetism and states what is now known as Curie’s law.


During experiments with cathode ray tubes, German physicist Wilhelm Roentgen discovers a previously unknown form of electromagnetic radiation, the x-ray.


The first large-scale hydroelectric power plant, located in North America at Niagara Falls, begins delivering power.


A German-American electrical engineer, Charles Steinmetz, applies the mathematics of complex numbers to the analysis of AC circuits.


Pieter Zeeman, a student of Dutch physicist Hendrik Lorentz, demonstrates that a magnetic field can split the spectral line of a light source into multiple components with different frequencies (the Zeeman effect).


French physicist Antoine-Henri Becquerel first observes natural radioactivity.


Italian-Irish inventor Guglielmo Marconi receives a patent for the radio, a device that enables the wireless transmission of electromagnetic waves.


J.J. Thomson carries out several experiments that lead him to conclude that cathode rays consist of a stream of negatively charged particles much smaller than an atom, dispelling the long-held belief that the atom was indivisible.


German physicist Karl Braun invents the cathode-ray oscilloscope, a means of visibly displaying graphical representations of electromagnetic signals. The cathode ray tube that the device contains eventually evolves into other types of electronic displays, including the receiving screen of the television.


German physicist Wilhelm Wien determines that the so-called “canal rays” discovered by his compatriot Eugene Goldstein in1886 are the positively charged equivalent of cathode rays.


Valdemar Poulsen, a Danish engineer, invents the telegraphone, an early magnetic recording device designed to record telephone conversations.


Ernest Rutherford, a physicist from New Zealand, determines that the rays that Becquerel discovered to be emitted from uranium (1896) are composed of two discrete forms of radiation, which he terms alpha rays and beta rays.


Waldmar Jungner of Sweden develops the rechargeable nickel-cadmium battery.

Next Section Arrow1900-1909

© 1995–2014 National High Magnetic Field Laboratory • 1800 E. Paul Dirac Drive, Tallahassee, FL 32310–3706 • Phone: (850) 644–0311 • Email: Webmaster

NSF and State of Florida logos NSF logo State of Florida logo

Site Map   |   Comments & Questions   |   Privacy Policy   |   Copyright   |   This site uses Google Analytics (Google Privacy Policy)
Funded by the National Science Foundation and the State of Florida