César-Mansuéte Despretz

. César-Mansuéte Despretz (1791-1863) studied phenomena related to thermodynamics, heat transfer, sound, electricity, combustion, and the properties of fluids. In the field of thermodynamics he researched the nature of latent heat, the vapor pressure of liquids, and the compressibility of gases. He proved that the law of ideal gases was not exact, that the compressibility of liquids decreased as the pressure was increased, that the density of water and saline solutions presented a maximum value, which for water occurred at 4 o
C, and that for saline solutions the maximum decreased with concentration. He built the first electric arc oven and combined its action with that of a very large burning glass and a blowpipe to realize the diffusion, fusion, and volatilization of refractory bodies. Using the discharge of the Ruhmkorff coil he approximated the transformation of pure sugar carbon into crystals having all the properties of pulverized diamond