1. Introduction
2. The Fifth Congress of Russian Physicists
3. On Comrade Timiryazev's Attitude to Modern Science
4. On the Bicentenary of Isaac Newton's Death. Foreword to the Articles by A. Einstein and J.J. Thomson
5. Marian Smoluchowski (On the tenth anniversary of his death)
6. Mechanical Materialism and Modern Physics (Section 1)
7. Mechanical Materialism and Modern Physics (Section 2).