This appendix reproduces most of the material contained in an envelope marked ‘Solvaykongressen 1927’, held in the Bohr Archive in Copenhagen. This material concerns the discussions at the Solvay conference, in particular Bohr's contributions and the general discussion. It has not been microfilmed, and only brief extracts have been published previously, in Bohr's Collected Works (Bohr 1985, pp. 103–5), where they are published together with some brief descriptions and comments (Bohr 1985, pp. 35–7, 100 and 478–9). The material consists of the following.

(1) In J.-É. Verschaffelt's hand (ten-and-a-half densely written pages), the transcripts of Bohr's major discussion contributions (after Compton's report and during the general discussion). These transcripts were presumably prepared on the basis of the (shorthand) notes taken during the conference, and they contain a large number of gaps. They are marked (in Danish) at the top: ‘Verschaffelt – sent to Bohr’, and they are evidently the material that Verschaffelt had supplied in order for Bohr to work out a final version of his contributions. The language is mainly English, with some German and French (and the annotation in Danish at the top).