Periodic Precipitation Structures

RECENT correspondence¹ has indicated that it is possible to explain the formation of periodic precipitation structures without invoking the aid of colloid-chemical principles. The amount of work which has been done on this subject is probably greater than even those who have made valuable contributions are aware. During the past ten years I have been collecting a bibliography, and I have recently had the assistance of the Science Library, South Kensington, through the kindness of Dr. S. C. Bradford. My collection now contains almost five hundred references. The investigations include not only periodic structures formed by chemical double decomposition, both with and without the presence of colloids, but also those produced by salting-out, coagulation, crystallisation (from melts and from solutions), condensation, evaporation, desiccation, and sedimentation.