Julius Robert von Mayer

Julius Robert von Mayer
Julius Robert von Mayer
Born	November 25, 1814 Heilbronn
Died	March 20, 1878(1878-03-20) (aged 63) Heilbronn
Nationality	Germany
Fields	Physics
Alma mater	University of Tübingen
Known for	First law of thermodynamics
Influenced	William Thomson
Notable awards	Copley Medal (1871)

Julius Robert Mayer (November 25, 1814 – March 20, 1878) was a German physician and physicist and one of the founders of thermodynamics. He is best known for enunciating in 1841 one of the original statements of the conservation of energy or what is now known as one of the first versions of the first law of thermodynamics, namely that "energy can be neither created nor destroyed". In 1842, Mayer described the vital chemical process now referred to as oxidation as the primary source of energy for any living creature. His achievements were overlooked and priority for the discovery of the mechanical equivalent of heat was attributed to James Joule in the following year. He also proposed that plants convert light into chemical energy.

Von Mayer was born on November 25, 1814 in Heilbronn, Württemberg (Baden-Württemberg, modern day Germany), the son of a pharmacist. He grew up in Heilbronn. After completing his Abitur, he studied medicine at the University of Tübingen, where he was a member of the Corps Guestphalia, a German Student Corps. During 1838 he attained his doctorate as well as passing the Staatsexamen. After a stay in Paris (1839/40) he left as a ship's physician on a Dutch three-mast sailing ship for a journey to Jakarta.

Although he had hardly been interested before this journey in physical phenomena, his observation that storm-whipped waves are warmer than the calm sea started him thinking about the physical laws, in particular about the physical phenomenon of warmth and the question whether the directly developed heat alone (the heat of burning), or the sum of the quantities of heat developed in direct and indirect ways are to be accounted for in the burning process. After his return in February 1841 Mayer dedicated his efforts to solve this problem.