Haber worked in a variety of areas while at Karlsruhe, making significant contributions in several areas. In the area of dye and textiles, he and Friedrich Bran were able to theoretically explain steps in textile printing processes developed by Adolf Holz. Discussions with Carl Engler prompted Haber to explain autoxidation in electrochemical terms, differentiating between dry and wet autoxidation. Haber's examinations of the thermodynamics of the reaction of solids confirmed that Faraday's laws hold for the electrolysis of crystalline salts. This work led to a theoretical basis for the glass electrode and the measurement of electrolytic potentials. Haber's work on irreversible and reversible forms of electrochemical reduction are considered classics in the field of electrochemistry. He also studied the passivity of non-rare metals and the effects of electric current on corrosion of metals. In addition, Haber published his second book, "Thermodynamik technischer Gasreaktionen : sieben Vorlesungen" (1905) trans. "Thermodynamics of technical gas-reactions : seven lectures" (1908), later regarded as "a model of accuracy and critical insight" in the field of chemical thermodynamics.