The four surveys contained in this volume illustrate widely diverse aspects of imaging and electron physics. The first two chapters address applications of electron microscopy, including the role of this technique in mineralogy and a study of the high- resolution electron microscopy of quasicrystals. The latter is actually a short monograph presenting the underlying crystallography and explaining in detail how the corresponding images and diffraction patterns should be interpreted. The third contribution is an account of a new approach to deconvolution in image processing in which the author, by associating a polynomial with the gray-level values of (discrete) images, shows that it is possible to invert the convolutional relation that describes many kinds of image formation. The volume ends with a detailed discussion of the dual de Broglie wave, including a critical account of new developments in the debate over the existence and role of such a wave.