GIBBS, JOSIAH WILLARD. Elements of Vector Analysis. New Haven, 1881-4. PRESENTATION COPY, inscribed "from the author" on front wrapper--On the Equilibrium of Heterogeneous Substances. Abstract by the author. Offprint from: The American Journal of Science and Arts, Vol XVI, Dec., 1878--Equilibrium of Heterogeneous Substances. Offprint from: Transactions of the Connecticut Academy of Arts and Sciences. Vol III, Part 1, pages 108-248 and Part 2, pages 343-524. New Haven, 1874-78--On the Vapor-Densities of Peroxide of Nitrogen, Formic Acid, Acetic Acid, and Perchloride of Phosphorus. Offprint from: The American Journal of Science and Arts. Vol. XVIII, 1879. Together, 4 papers bound in one, 8vo, buckram; 3 front wrappers bound in.