New York became the first US court to allow blood test results to be used as evidence.
Source
New York state became the first to require license plates on automobiles.
Twelve doctors at Massachusetts General Hospital in Boston performed the first successful reattachment of a human limb – it was the severed arm of a boy.
Francis Crick & James Watson's discovery of the double-helix structure of DNA was formally announced.
Anti-Discrimination Bill was signed in New York, US.
While observing a compass needle, scientist Hans Christian Ørsted discovered electromagnetism.
