The year 1940 in science and technology involved some significant events, listed below.

Biochemistry

• August 24 - Howard Florey and a team including Ernst Chain, Arthur Duncan Gardner, Norman Heatley, M. Jennings, J. Orr-Ewing and G. Sanders at the Sir William Dunn School of Pathology, University of Oxford, publish their laboratory results showing the in vivo bactericidal action of penicillin. They have also purified the drug.^[1][2]

Biology

• February 2 - The first transposons are discovered in maize (Zea mays, aka corn) by Barbara McClintock.

Chemistry

• February 27 - The radioactive isotope carbon-14 is discovered by Martin Kamen and Sam Ruben at the University of California, Berkeley.^[3]
• May 15 - Women's stockings made of nylon are first placed on sale across the United States.^[4]
• The radioactive element Astatine is synthesized by Dale R. Corson, Kenneth Ross MacKenzie and Emilio Segr at the University of California, Berkeley.^[5]
• Neptunium, the first transuranic element, is synthesized by Edwin McMillan and Philip H. Abelson at the University of California, Berkeley.^[6]
• Robert McCance and Elsie Widdowson publish the standard text The Chemical Composition of Foods.^[7]

Computer science

• January 8 - In the history of computing hardware, Bell Labs' Complex Number Calculator, a relay-based calculator for complex numbers, is completed under the direction of George Stibitz.^[8]
• May–August - Alan Turing and Gordon Welchman at the United Kingdom Government Code and Cypher School, Bletchley Park, design the British Bombes to help decrypt Wehrmacht Enigma machine signals.^[9]

Medicine

• At Johns Hopkins Hospital in the United States, Dr. Austin T. Moore (1899 1963) performs the first metallic hip replacement surgery.

Physics

• January 5 - FM radio demonstrated to the FCC for the first time.
• Cavity Magnetron invented by John Randall and Harry Boot.

Technology

• May 26 - First free flight of Igor Sikorsky's Vought-Sikorsky VS-300 helicopter, in the United States.
• September 21 - American Bantam deliver the first prototype BRC Quarter-Ton General Purpose Vehicle – the four-wheel drive Jeep, designed by Karl Probst.^[10]
• November 7 - The new Tacoma Narrows Bridge collapses under wind pressure.

Births

• April 1 - Wangari Muta Mary Jo Maathai (died 2011), Kenyan biologist and Nobel Peace Prize winner.
• June 22 - Daniel Quillen (died 2011), American mathematician.
• November 26 - Enrico Bombieri, Italian-born mathematician.

Deaths

• March 9 - Robert Gunther (born 1869), English historian of science.
• April 13 - Pierre Marie (born 1853), French neurologist.
• November 8 - Arthur Vierendeel (born 1852), Belgian civil engineer.
• December 16 - Eug ne Dubois (born 1858), Dutch paleoanthropologist.

References

fr:1940 en science he:1940 mk:1940 no:Vitenskaps ret 1940 nn:Vitskap i 1940 pl:1940 w nauce pt:1940 na ci ncia ru:1940 sv:Vetenskaps ret 1940