1. a) cf. O. T. Benfey, ed., Classics in the Theory of Chemical Combination, Krieger, Malabar, FL, 1981, pp. 1-108.
2. b) id., From Vital Force to Structural Formulas, Houghton Mifflin, Boston, MA, 1964, pp. 1-75.
3. The term “constitution” was used prior to 1858, if perhaps vaguely. In the title of Loschmidt’s 1861 booklet (ref. 8) it includes connectivity and it is in this latter sense that the term has been defined in a recent text: E. L. Eliel, S. H. Wilen, Stereochemistry of Organic Compounds, Wiley, 1994. In the same text “structure” is defined as the complete three-dimensional array of the atoms in a molecule: Structure = Constitution + Configuration + Conformation. Butlerov (ref. 17) in his original definition of structure calls it the manner of the mutual linkage of atoms in a chemical compound, and while in 1861 this may have been synonymous with constitution, in modern parlance the “manner of mutual linkage” may be considered to include the three-dimensional array, i.e. configuration and conformation.
4. A. S. Couper, C. R. Acad. Sci. 46, 1157 (1858).
5. A. S. Couper, C. R. London, Edinburgh, Dublin Philos. Mag. J. Sci. [4] 16, 104 (1858).