Pierre Chappuis (physicist)

Pierre Chappuis (1855-1916) was a Swiss physicist known for his precision measurements and contributions to thermometry. He worked extensively at the International Bureau of Weights and Measures (BIPM) in Sèvres, France, alongside prominent scientists such as Henri-Victor Regnault and Charles-Édouard Guillaume.

Chappuis's research focused on the accurate determination of fundamental physical constants, particularly in the areas of temperature and pressure. He made significant improvements to the air thermometer and conducted precise measurements of the density of water at different temperatures. His work helped refine the definition of the kilogram and contributed to the establishment of a more accurate international temperature scale.

His publications include detailed reports on his experimental methods and results, which were widely cited and considered benchmarks in metrology for many years. He is remembered for his meticulous attention to detail and his commitment to advancing the science of measurement.