Professor P. P. Ewald

Abstract

I first got to know Ewald personally at the famous meeting at his mother's house on the Ammersee in Bavaria. It was not long after the end of World War I. Ewald had been developing the dynamic theory of X-ray diffraction, and he arranged a conference to discuss this and other X-ray analysis problems. We stayed in the inn at Holzhausen and our meetings were held in Mrs Ewald's studio. The English contingent consisted of Darwin, James and myself. Before the war Darwin had worked out the theoretical treatment of diffraction by perfect and imperfect crystals and James and I felt we were bringing along the British seeded player to represent our country at the meeting. To our consternation we found that Darwin had typically omitted to refresh his memory of his own theories and was unable to explain them when he got up to make his contribution! Most of the pioneers of X-ray analysis were there, it was a wonderful reunion. We were most hospitably looked after; and if I remember rightly the Ewald children put on a play especially planned to celebrate the meeting. We had a job to assemble enough garments for our bathes in the Ammersee I had to borrow the chambermaid's bathing dress and it had a little frilly skirt. We had a grand time and we started that personal acquaintance amongst crystallographers which has been so much a characteristic of the international meetings ever since.