John William Nicholson, FRS (1 November 1881 – 3 October 1955) was an English

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 mathematician

Mathematician

A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....

.

Based on the results of astronomical

Astronomy

Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

 spectroscopy

Spectroscopy

Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...

 of nebula

Nebula

A nebula is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases...

 he proposed in 1911 the existence of several yet undiscovered elements. Coronium

Coronium

Coronium was the name of a suggested chemical element, hypothesised in the 19th century. It was named after the solar corona.During the total solar eclipse of 7 August 1869, a green emission line of wavelength 530.3 nm was observed in the coronal spectrum...

 with an atomic weight of 0.51282, nebulium

Nebulium

Nebulium was a proposed element found in a nebula by William Huggins in 1864. The strong green emission lines of the Cat's Eye Nebula, discovered using spectroscopy, led to the postulation that an as yet unknown element was responsible for this emission...

 wit a weight of 1.6281 and protofluorine with a weight of 2.361. Ira Sprague Bowen

Ira Sprague Bowen

Ira Sprague Bowen was an American astronomer. In 1927 he discovered that nebulium was not really a chemical element but instead doubly ionized oxygen.-Life and work:...

 was able to attribute the spectroscopical lines to doubly ionized oxygen

Doubly ionized oxygen

Doubly ionized oxygen is a forbidden line of the ion O2+. It is significant in that it emits light in the green part of the spectrum primarily at the wavelength 500.7 nanometres and secondarily at 495.9 nm. Concentrated levels of [O III] are found in diffuse and planetary nebulae...

making the new elements obsolete for their explanation.