Principle of Conservation of Energy

Helmholtz obtained his medical degree at the age of 21 and was inducted into the army. While in the army, he was able to build a small laboratory and to con- tinue his early research, which concerned metabolic processes in the frog. Helmholtz demonstrated that food and oxygen consumption were able to account for the total energy that an organism expended. He was thus able to apply the already popular princi- ple of conservation of energy to living organisms. According to this principle, which previously had been applied to physical phenomena, energy is never created or lost in a system but is only transformed from one form to another. When applied to living organisms, the principle was clearly in accordance with the materialist philosophy because it brought physics, chemistry, and physiology closer together. In 1847 Helmholtz published a paper titled “The Conservation of Force,” and it was so influential that he was released from the remainder of his tour of duty in the army.