He published Aristoteles fiber die Farben (1849), Aristoteles' acht Blcher der Physik (1857), and numerous minor articles on smaller points, such as the authenticity of the thirty-eight books of the Problems. The work by which he is best known is the Geschichte der Logik im Abendland (Leipzig, 1855-1870).
To judge only by the negative evidence of the decree of Aristoteles which records the terms of alliance of the second confederacy (below), we gather that in the later period at least of the first league's history the Athenians had interfered with the local autonomy of the allies in various ways - an inference which is confirmed by the terms of "alliance" which Athens imposed on Erythrae, Chalcis and Miletus.