In the teaching of the physics connected with the diffraction of x-rays, as well as the daily research practice of taking x-ray diffraction pictures, it is customary to take the pictures on flat x-ray film or upon sheets of film which has been curved into cylinders. In physics teaching this practice has very definite handicaps and appears to be somewhat indirect, because the theoretical treatment of the diffraction of x-rays is more directly connected to the geometry of spheres. We have, therefore, as a teaching aid, coated the inside surface of some hollow glass spheres with photographic emulsion and have recorded upon these spheres the diffraction of x-rays from small crystals located at their centers. Some of the results are shown in Figs. 1 a, b, and c.