jan 1, 1869 - Dimitri Mendeleev (serial killer)
Description:
In 1869 Russian chemist Dimitri Mendeleev started the development of the periodic table, arranging chemical elements by atomic mass. He predicted the discovery of other elements, and left spaces open in his periodic table for them. Thomson first discovered electrons; small negatively charged particles in an atom.Added to timeline:
Date:
jan 1, 1869
Now
~ 156 years ago