1904 in science

List of years in science (table)
... 1894 1895 1896 1897 1898 1899 1900 ... 1901 1902 1903 1904 1905 1906 1907 ... 1908 1909 1910 1911 1912 1913 1914 ...
Art Archaeology Architecture Literature Music Philosophy Science +...

The year 1904 in science and technology involved some significant events, listed below.

Astronomy

• Johannes Franz Hartmann discovers the interstellar medium.
• Edward Walter Maunder plots the first sunspot "butterfly diagram".
• Notable asteroid 522 Helga is discovered by Max Wolf in Heidelberg.
• December 3 – The sixth moon of Jupiter, later called Himalia, is discovered at Lick Observatory.

Mathematics

• Henri Poincaré discovers the Poincaré homology sphere, leading him to formulate the Poincaré conjecture.
• Helge von Koch describes the "Koch snowflake", one of the earliest fractal curves described.
• Charles Spearman develops his rank correlation coefficient.
• Ernst Zermelo formulates the axiom of choice to formalize his proof of the well-ordering theorem.

Medicine

• Epinephrine first artificially synthesized by Friedrich Stolz.
• Antoni Leśniowski presents to a meeting of the Warsaw Medical Society a surgical specimen of an inflammatory tumour of the terminal ileum with a fistula to the ascending colon, consistent with what will later become known as Crohn's disease.

Physics

• Vacuum tube invented by John Ambrose Fleming.
• James H. Jeans's The Dynamical Theory of Gases is published in Cambridge.
• J. J. Thomson proposes the plum pudding model for the atom.
• Hantaro Nagaoka develops the Saturnian model for the atom.

Technology

• July 23 – A continuous track tractor is patented by David Roberts of Richard Hornsby & Sons of Grantham in England.
• The first diesel engined submarine, the Z, is built in France.
• The Heckelphone variety of oboe is invented by Wilhelm Heckel and his sons.
• The sleeve valve is invented by Charles Yale Knight.
• The turbine-powered Bliss-Leavitt torpedo, designed by Frank McDowell Leavitt and manufactured by the E. W. Bliss Company of Brooklyn, is put into service by the United States Navy.
• Lucien Bull produces the first successful chronophotography (of insect flight), working in France.
• Rue Franklin Apartments, Paris, are completed by Auguste Perret and his brother Gustave, an early example of an exposed reinforced concrete frame building.

Zoology

• First identification and last confirmed sighting of the Choiseul pigeon in the Solomon Islands.

Awards

• Nobel Prizes
  • Physics – John William Strutt, 3rd Baron Rayleigh
  • Chemistry – Sir William Ramsay
  • Medicine – Ivan Pavlov

Births

• January 26 – Ancel Keys (died 2004) American nutritionist.
• March 13 – René Dumont (died 2001), French agronomist.
• March 20 – B. F. Skinner (died 1990), American behavioral psychologist.
• April 11 – Arthur Mourant (died 1994), Jersiais hematologist.
• April 22 – J. Robert Oppenheimer (died 1967), American physicist.
• July 5 – Ernst Mayr (died 2005), German-born evolutionary biologist.
• August 5 – Kenneth V. Thimann (died 1997), English-American plant physiologist and microbiologist known for his studies of plant hormones.
• August 17 – Cornelis Simon Meijer (died 1974), Dutch mathematician.
• August 28 – Secondo Campini (died 1980), Italian jet pioneer.
• November 11 – J. H. C. Whitehead (died 1960), British mathematician.

Deaths

• May 10 – Henry Morton Stanley (born 1841), Welsh-born explorer and journalist.