John Dalton

Quaker schoolteacher whose atomic theory turned chemistry into a science of countable particles.

Core Principles & Analysis

• His 1803-08 atomic theory explained fixed and multiple proportions by discrete atoms with characteristic weights.
• He published the first table of relative atomic weights.
• Color-blind himself, he studied the condition so carefully it is still called daltonism.

Specifications & Metrics

• ERA: 1766 – 1844