The paper by Irving Langmuir investigates the adsorption of gases on glass, mica, and platinum surfaces. Langmuir's theory posits that adsorption is a physical phenomenon where gas molecules condense on the surface due to the attractive forces between the molecules and the surface atoms. The adsorbed layer is typically one molecule thick, and the adsorption process is influenced by the chemical nature of the surface forces. Langmuir developed a quantitative theory for adsorption on plane surfaces, considering various scenarios such as simple adsorption, multiple types of elementary spaces, amorphous surfaces, and atomic adsorption. The theory predicts that the amount of adsorbed gas varies with pressure and temperature, and it provides equations to describe these relationships. Experimental methods using mica, glass, and platinum surfaces are described, including techniques to measure the amount of gas adsorbed and to correct for thermal effusion. The results support the theory and provide insights into the complex phenomena of adsorption.The paper by Irving Langmuir investigates the adsorption of gases on glass, mica, and platinum surfaces. Langmuir's theory posits that adsorption is a physical phenomenon where gas molecules condense on the surface due to the attractive forces between the molecules and the surface atoms. The adsorbed layer is typically one molecule thick, and the adsorption process is influenced by the chemical nature of the surface forces. Langmuir developed a quantitative theory for adsorption on plane surfaces, considering various scenarios such as simple adsorption, multiple types of elementary spaces, amorphous surfaces, and atomic adsorption. The theory predicts that the amount of adsorbed gas varies with pressure and temperature, and it provides equations to describe these relationships. Experimental methods using mica, glass, and platinum surfaces are described, including techniques to measure the amount of gas adsorbed and to correct for thermal effusion. The results support the theory and provide insights into the complex phenomena of adsorption.