Pauli replies to Schrödinger's letter of the 18th May 1926. He writes about the connection between quantum mechanics and Schrödinger's wave mechanics. He talks about the transition to classical quantum theory for large quantum numbers. He comments on volume integral and on the higher rotational states of the electron.

Pauli summarizes his work on spectral intensities using the correspondence principle. He compares it with Ornstein's results. He makes remarks on satelite-lines paper (in: Naturwissenschaften : 12 (1924), pp.741).

Pauli says his difficulties with model pictures. He reports on his "generalization" of Stoner's work for closing of shells. He comments the new edition of Sommerfeld's Atombau.

Pauli talks about spectral terms for oxygen. He finds support for Landé-Heisenberg "branching rule" and "Heisenberg's theory". He comments Kronig's formulas. He makes personal remarks on Lenz.

Pauli discusses and criticizes the Sommerfeld and Unsöld's paper on spectroscopy and their electron-spin idea for hydrogen fine structure.

Pauli discovers a mistake in Uhlenbeck's calculation of a certain integral.

Pauli expresses doubts about Wentzel's results concerning higher relativity corrections for the H-atom. He makes remarks about the mathematical method used by Wentzel.

Pauli writes about the probability interpretation of wave-mechanical quantities. He comments on Fermi statistics for degenerate gases. He asks for clarification on Wentzel's method for the solution of Schrödinger's equation. He writes about an application of quantum mechanics to X-ray absorption. He writes about a meeting of physicists in Hamburg.

Pauli writes about possible candidates for a professorship in Leipzig. He writes more about Gordon's work on the spacial distribution of recoil electrons according to Schrödinger's wave mechanics.

Pauli writes about the success of the hypothesis of the magnetic electron. He writes about the connection of Schrödinger's equation with quantum mechanics. He comments on the conclusions of Heitler's paper on statistics. He writes about the second order Stark effect.