1. This is the odd date out. It comes from examining drafts of Meyer’s textbook dated before Mendeleev’s 1869 publications. See Karl Seubert, “Zur Geschichte des periodischen Systems,” Zeitschrift für anorganische Chemie 9 (1895): 334–338.
2. Sharing credit between Meyer and Mendeleev used to be more common than it is today. See, for example, Curt Schmidt, Das periodische System der chemischen Elemente (Leipzig: Johann Ambrosius Barth, 1917), 22
3. and Karl Seubert, ed., Das natürliche System der chemischen Elemente: Abhandlungen von Lothar Meyer und D. Mendelejeff (Leipzig: Wilhelm Engelmann, 1895), 122.
4. Ludwig Wittgenstein, Philosophical Investigations, tr. G. E. M. Anscombe (Oxford: Basil Blackwell, 1953), § 76, 36e.
5. For the classic and still relevant discussion of this problem, see Robert K. Merton, “Priorities in Scientific Discovery: A Chapter in the Sociology of Science,” American Sociological Review 22 (1957): 635–659;