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Rh apparatus, appliances, and processes in pharmacy and chemical analysis, which he embodied in his "Lehrbuch der pharmaceutischen Technik" ("Manual of Pharmaceutical Practice"), published in 1846. This remarkable work has since been reprinted in five editions, and has been twice translated into French, and into English by Professor Redwood, of London, and edited for American use, in 1848, by the late Professor William Procter, Jr., of Philadelphia.

In 1847 Mohr completed a commentary on the Prussian Pharmacopoeia in two volumes, a work replete with original research and thought, and characterized by frank critical analysis of both the excellences and the defects of the Prussian standard. This work has also been republished in five editions. A smaller volume on the art of dispensing (Receptir Kunst), mainly intended for the instruction and use of physicians, published in 1854, completes the list of Mohr's separate pharmaceutical works, while his numerous contributions to the pharmaceutical journals of Germany, continued almost during his lifetime, were of great importance, covering the domain of practical pharmacy, and embracing many processes as well as manipulations and apparatus, invented or perfected by him and now widely adopted and in general use everywhere.

The principles and great practical value of the volumetric method of estimation in chemical analysis, recently introduced by Gay-Lussac, Marguerite, and others, attracted at once Mohr's quick and inquisitive mind; recognizing both the simplicity and accuracy of this method, he promptly applied his study and talents to its improvement, and soon brought volumetric analysis to such a perfection and comparatively ready execution that his "Manual of Volumetric Analysis" ("Lehrbuch der chemisch-analytischen Titrirmethode"), published in 1855, met with general and unqualified acceptance; since then four revised and enlarged editions have been published, and it has been translated into most civilized languages, and up to the present time is regarded as the standard work in this branch of chemical analysis, which has been of great value and use in the development and advance of chemical industry.

During these active years of Mohr's life it was, however, not only the practical and analytical application of pharmacy and chemistry that received his attention and the fruits of his labors and accomplishments, but likewise the theory of science and popular instruction; already in 1864 Mohr had established himself as "Privat-Docent" in pharmacy, chemistry, and geology at the University of Bonn, where he was appointed as Professor of Pharmacy and Chemistry in 1867, and where he published in 1868, aside from many scientific as well as popular contributions to journals, his most important work on theoretical chemistry, "The Mechanical Theory of Chemical Affinity," being a continuation and perfection of his first similar essay published in 1837.