Abstract: The present invention is a display apparatus having a display surface formed by an array of contiguous elements which are rotatable about vertical shafts to display a surface of contrasting appearance to the background appearance of the display surface thereby forming a mosaic displaying information. A column of solenoid operated actuator devices is driven along the back of the display surface and selected devices operate to rotate selected ones of the elements in each vertical shaft. The elements have a generally cubic overall shape with their vertical surfaces being cylindrically concave to allow rotation of an element without causing movement of a contiguous element. The bottom surfaces of the elements are grooved and arranged so as to co-operate with fixed horizontal members to provide an indexing arrangement. In addition, vertically extending channels communicate with the bore of each element to allow rain water to flow freely down the display surface.