sophical Society in 1876 declared that the methods of Gibbs "seemed to throw a new light upon thermodynamics." Copies of the work were consequently much prized and sought after in England about this time; but the most substantial recognition of Gibbs's work was to come from Holland, where a long line of physical chemists, van der Waals, Roozeboom, van't Hoff, Lorentz, Schreinemakers, Stortenbeker, van Laar, Hoitsema, Kamerlingh Onnes, have developed his ideas with very substantial additions to their own fame. Parallel with the work of these men and the development of the important laws of Goldberg and Waage, van't Hoff and Arrhenius, the science of physical chemistry, which DuBois Reymond called "the chemistry of the future," came into being under the leadership of Ostwald in Germany and (since 1896) of Professor Bancroft in America. With the gradual recognition of the significance of "reversible reactions" and of Sainte-Claire-Deville's doctrine of chemical dissociation, the algebraic formulæ of Gibbs became slowly converted into working theories of physical chemistry. In 1892 Ostwald translated Gibbs's papers as "Thermodynamische Studien" and part of them were rendered into French in 1899 by Le Chatellier. The purely mathematical part of Gibbs's theory has been developed in extension by the labors of Duhem, Paul Sorel, Trevor, Bancroft, van der Waals, Larmor and Bryan. Roozeboom, van der Waals and Bancroft have made the widest applications of his ideas to chemistr}, while their best interpretation from the dynamic or energetic point of view is that of Ostwald and of Larmor, Although a genial and engaging writer in his discourse on "Multiple Algebra" and his biographical sketches, the strictly scientific papers of Gibbs are not, like those of Maxwell, Boltzmann and Hertz, attractive reading. Indeed, it has been said of his memoir on equilibrium that Ostwald is one of the few people in the world who ever read every word of it, for the student is repelled, not so much by its bristling quickset of some seven hundred formula as by the severe and austere reasoning and a literary style that is swift in movement and (doubtless from the very nature of the subject matter) tense and dry in quality. Although endowed with the scientific imagination of a man of genius, Gibbs's strong point in demonstration was unusual quickness of intelligence
- The difference between reversible and irreversible chemical processes could hardly be better indicated than in the following comparison of van't Hoff: "Kill a chicken and prepare chicken soup; it would then be very difficult to get your chicken again. This is because preparing chicken soup is not reversible. On the contrary, let water evaporate or freeze, it will be easy to reproduce the water" (J. Phys. Chem., 1905, IX., 87). The distinction between reversible and irreversible reactions is thus a physico-chemical or thermodynamic conception, depending, like the operations of mechanical systems, upon the initial conditions, under which the phenomenon takes place.
- See Ostwald, "Lehrb. d. allg. Chemie," Leipzig, 1896, II., 2. Th., 114-5.
- See "Encycl. Britan.," 10th ed., XXVIII., sub voce Energetics.