History of Watchmaking

Series production began of self-winding wristwatches with an oscillating weight, based on Harwood’s patent (Selza, Fortis and Blancpain using blanks by A. Schild S.A.).
Rolex created the Oyster wristwatch with water-resistant case and crown.
Mercedes Gleitze wore one when she swam the Channel in 1927.

World history

The Scottish inventor John Logie Baird demonstrated his procedure for receiving images by cathode ray tube before the Royal Institution of London. He called his invention a "televisor".
The American physicist Robert Hutchings Goddard successfully launched a rocket propelled by a blend of petrol and liquid oxygen. It reached a height of 12.50 metres and a speed of 100 kph.

Swiss history

Switzerland’s population reached 4 million.

Art and Culture

On learning the death of Rudolph Valentino from acute peritonitis, hysterical crowds gathered outside the New York clinic where the silent-movie heartthrob had passed away.
In Berlin, the German director Fritz Lang premiered his film, Metropolis.
Death of the painter Monet.