Several books have been published on mass radiography in other nations, such as "Mass Miniature Radiography" by Trail and others, published by J. and A. Churchill Ltd., London, 1943, and "Mass Miniature Radiography of Civilians" by Clark and others, published by His Majesty's Stationery Office, London, 1945. However, this is the first book to be published on the subject in the United States. It is indeed fortunate that this first volume was written by physicians who have had wide experience in tuberculosis work and in the fundamentals of radiography, since at this particular time the value of the x-rays in the diagnosis of tuberculosis is greatly exaggerated, even to the point of making final diagnoses with no evidence whatever except shadows seen on x-ray films.
The limitations of the x-rays are numerous in the diagnosis of chest diseases. Therefore the public and even the medical profession could have been led