Follow Hippolyte Fizeau through 1 dated historical records for France.
A chronological timeline drawn from matching World History Database records.
The first successful entirely earthbound measurement of the speed of light is carried out by Hippolyte Fizeau, measuring the speed of light in air, which is slower than the speed of light in vacuum by a factor of the refractive index of air 1.0003
These dates and descriptions come from the historical_events database. Exact duplicate records have been collapsed. Names are grouped by the country, Name 2 and Name 1 fields; records with missing Name 2 cannot be reliably assigned to an individual biography. Check the underlying sources before formal citation.