18h 14min, apr 20, 1865 y - Law of Octaves
Description:
Newland makes his law of octaves. He arranged them in ascending atomic masses and realised that a pattern reoccured every 8 elements, hence the law of octaves.
He then predicted some more periodic trends.
Added to timeline:
Date:
18h 14min, apr 20, 1865 y
Now
~ 159 years ago