Robert Mayer was a brilliant but unlucky man. He originated the concept of conservation of energy, now considered the first law of thermodynamics, and was the first person to determine the mechanical equivalent of heat. He was a physician by training and did not have a reputation as a scholar in the scientific community. Thus, it was up to later scientists to "rediscover" the landmark research Mayer had performed years earlier. Mayer was born in Heilbronn, Germany, in 1814. He was the youngest son of an apothecary, and the only son who chose not to enter his father's profession. He enrolled at the University of Tubingen and, despite being expelled in 1837 for his participation in a secret society, received his medical degree in 1838. In 1840 he signed on as a ship's doctor for a vessel sailing to East Indies. It was on this ship, near Java, that Mayer began to...