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Historians and scientists alike have called Josiah Willard Gibbs one of the greatest scientists of the 19th century; some have declared his discoveries to be as fundamental in nature as those of Galileo and Newton. Gibbs made important contributions in vector analysis, electromagnetic theory, and statistical mechanics, but he is best known for developing the modern method of thermodynamic analysis.

Throughout his career, Gibbs published many books, including “On the Equilibrium of Heterogeneous Substances,” which introduced the Phase Rule, said to be the most important single linear equation in the history of science.

Gibbs also wrote five papers on the electromagnetic theory of light, prepared classroom notes that eventually became the first English language work on modern vector analysis, and in 1902 published his Elementary Principles in Statistical Mechanics.

For his extraordinary achievements, Gibbs received some of the most prestigious awards of his time, including the Rumford Prize of the American Academy of Arts and Sciences in 1880 and the Copley Medal of the Royal Society of London in 1901.

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