It may seem presumptuous for a mere radiologist to venture into the field of clinical medicine. The clinician's idea of a radiologist sometimes is that of a queer being who inhabits dark places, sees curious things, and talks a strange language compounded of wavelengths designated by Greek letters that remind one of college fraternities, of roentgens, and of the relative radiosensitiveness of different varieties of cells. It so happens that, when they undertook to acquire the extra knowledge essential for the sound practice of radiology, some radiologists were perverse enough to retain an interest in clinical medicine. I happen to be one of them. It is perhaps unfortunate that a larger proportion of those who have adopted this specialty have not seen fit to follow this example. In my own case, the circumstances of life have given me an exceptional opportunity to see and to examine a large number of