Keywords: Maxwell's letters plate IV.jpg en J C Maxwell's sketch of the thermodynamic surface for a water-like substance based on a theoretical construct proposed by J W Gibbs The curves are isothermals and isopiestics drawn by help of the Sun P M Harman ed The Scientific Letters and Papers of James Clerk Maxwell vol 3 1874-1879 Cambridge UK Cambridge University Press 2002 p 232 plate IV James Clerk Maxwell 1831 “ 1879 1875-07-08 PD-old-100 http //www sv vt edu/classes/ESM4714/methods/combo jpg James Clerk Maxwell Thermodynamic diagrams |