In radiography of the operation of fracture at the joint of the femur, it is necessary to reduce the time of the development of the film, as much as possible. Therefor, the prescription of the developer, the conditions. contrasts and sensitivity of a system where by the development and fixing combined into a single operation was tried out d and it was found to work satifactorily.
The tomography in which the X-ray tube and film were moved to the direction of the central X-ray and the ratio of the distance between the focus and the aimed plane to that between the aimed pland and the film was kept constant during the exposure, was named "adjustable tomography" temporarily. This method of roentgenography was theoretically studied and the results were as follows. 1) If the ratio of the moving distance of the X-ray tube to the maximum distance between the focus and the aimed plane was named the "moving rate" and represented by n, the product of the output of the X-ray tube and the exposure needed for this tomography would be (1-n) times of that needed for the roentgenography in the fixed position where the distance between the tube and the film was maximum. 2) To obtain the best pictures from the viewpoint of dimness of the aimed plane and aberration of the unaimed planes, the film and the X-ray tube were to be moved as close as possible to the object until the former restricted by it and the latter was limited by the magnifying power which was decided by the size of the focus, and the moving rate was to be kept at about 0.5.
We discussed on the applicability of Acrylite as a body phantom in deep radiotherapy in the previous report, and now reported in telecobalt therapy in this paper. We measured the attenuation curves and percentage depth dose curves of various field sizes in water and Acrylite. The total linear absorption coefficient of Co^<60> gamma rays in Acrylite was 1.17 times greater than that in water in proportion of their electron densities, e.g.the mass absorption coefficients of both materials coincided each other practically. On the otherhand, the ratio of depths giving the same depth doses was about 1.1,which was lower than the ratio of the absorption coefficient, and was dependent on the field size in some degree. While they were somewhat different in the state of the scatter, Acrylite was available practically to the phantom in consideration that the thickness of Acrylite multiplied by 1.1 was equivalent to that of water. The dosage at the rotation centre in the human pelvis was measured and compared with the calculated one by the Quimby's method using the depth dose data in water and Acrylite. Then the effective body contour as Acrylite was determined by the transit dose measurement. Absorption and scatter in the human pelvis as whole was closer to Acrylite than water, and Acrylite was able to use as pelvic phantom as it was.
An examination of the function of each lung is necessary for deciding the surgical treatment of pulmonary tuberculosis. The examination, however, requires expensive and special bronchospirometry and often is impossible to apply. Various methods of examination have been reported, most of which are very complicated and worth little. Therefore, the author, aiming at a simplification of the examination, devised a grid with lattices one centi-meter intervals ; using this grid, he studied various methods of chest-polisography in deep inspiration and deep expiration. From these roentgenograms, he could easily calculate the ratio of the capacities of the two lungs. The methods of polisography and calculation are described in this paper.