Abstract: "A theoretical and experimental investigation is made of the diffraction pattern produced by a slit, whose aperture varies uniformly from a constant value A to zero. The results of this investigation are applied to a proposed high speed camera. It is shown that diffraction effects are very serious and cannot be neglected. It seems, unless the suggested design of this high speed camera is changed, the camera will be of little use for accurate measurements, and photographs will show too much blue to give details."

"This report gives briefly a rather simple method for fabricating foils from uranium buttons. Two log sheets one of a U-238 run and one of a U-255 run are given."