Robert Mayer: Conservation of Energy and Venous Blood Colour

Abstract

The concept of conservation and transformation of energy was proposed by the 19th century doctor, Robert Mayer. This concept derives from a clinical observation. During the 1st centennial celebrations, the medical profession posed the question of whether Mayer had indeed observed what he claimed and took as the basis of the principle of conservation of energy: if the colour of venous blood in the tropics was lighter than in colder regions, then this was a result of a higher oxygen consumption to maintain body temperature. In this paper, it was shown that, based on Mayer’s data and contemporary physiology, this observation could indeed have occurred but for a different reason.