Pauli discusses the properties of spin matrices and efforts toward a quantum electrodynamics.

Pauli asks if Bohr could go through Heisenberg's manuscript dealing with a new conception of the Zeeman-effect.

Pauli writes about the Lorentz transform of the magnetic moment. He suggests a non-relativistic example of Thomas term.

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.

Pauli talks about his work with Heisenberg on field theory. He makes remarks on Dirac's electron theory.

Pauli says that Goudsmit told him about Thomas' calculations, and this confirms his ideas about the definition of the moment of the electron. Pauli gives some consideration to the implications of the model of the rotating

Pauli's interpretation of intercombination lines and the application of his model to several cases (Zeeman-effect). He expresses hope for the progress of physics through Heisenberg's mechanics.

Pauli asks if Kronig would be ready to be his assistant in Zürich. He writes about the conditions and colleagues there.

Pauli says that he will write to Kronig next year.

Pauli urges Kronig to come to Zurich for the summer term. Addendum for Kramers about Pauli's paper with Jordan.