Discovery: He was the first to recognize that the total pressure of a mixture of gases is the sum of the individual gases of the mixture. The part of the total pressure of a mixture that results from one gas is called the partial pressure of that gas.
Real World Example: The atmosphere is made up of nitrogen, oxygen, carbon dioxide, and water vapors. The total pressure is the sum of the partial pressures of each gas. The different partial pressures are the reason why we have different weather experiences.