jan 1, 400 BC - Democritus' Theory
Approximately 400 BC Democritus came up with a theory that everything was made up of tiny indestructible and indivisible particles. Before his time Aristotle's idea was accepted. Aristotle believed everything was composed of 5 elements - earth, water, air, fire, and aether - not tiny particles.
Added to timeline:
History of the Atom Project
Created by Jenna Barnes