Pauli says to Landé that he has sent off his paper for publication.

Pauli hopes to come to Copenhagen and to discuss radiation problems. He has now to write a Handbuch article for Springer on the problem of closed shells. He believes in a definite value of momentum of the atom in a stationary state, if this momentum is conceived as a dynamical (not kinematical) quantity. He writes also about the theory of multiplet intensities in an electric field, Ornstein's sum-rules, Kramer's dispersion theory and about the so-called Smekal-jumps (frequency of the external field goes to zero).

Pauli writes about the paper by Bohr, Kramers, Slater and its experimental refutation by Geiger and Bothe. Pauli explains that the concepts of motion and force have to be modified, but not the concept of energy. He writes of his support for Heisenberg's new ideas.

Heisenberg writes about progress in quantum mechanics, Born's and Jordan's contribution and mathematical representation of the new formalism.

Heisenberg writes about the quantum conditions for several degrees of freedom.

Pauli talks about a formula made by Kramers and about his doubts about Goudsmith's idea on the spin of the electron.

Letter written giving Pauli's first impressions of Schrödinger's article "Quantisierung als Eigenwertproblem published in Annnalen der Physik. He develops the connection with the quantum mechanics of the Göttingen Physicists.