Pauli letter collection: letter to Werner Heisenberg

Pauli comments on a manuscript by Heisenberg. The important progress lies in the recognition of the fact that all infinities are created by the field quantization. Mathematically things are satisfactory, but physically, no experimental consequences can be expected, because the neglect of the radiation-reaction forces is not legitimate. He remarks on coherent scattered radiation and on Weisskopf's and Delbrück's work on it. He writes of his thoughts on the significance of e$^{2}/(h.c) and of the concept of charge and its conservation.