The image is a vintage, black and white photograph depicting the effect of radium rays. It appears to be a scientific illustration, labeled 'FIG. 21.—Reversal produced by radium rays.' The central focus is a small, dark, circular spot, likely representing the source of the radium rays. Emanating from this spot are numerous, faint rays that spread outwards, creating a radial pattern. The rays are more concentrated near the center and gradually fade as they extend towards the edges of the image. The overall effect is a soft, diffused glow, with a darker background. The image has a grainy texture, typical of older photographic processes. The contrast is moderate, with a clear distinction between the central spot and the surrounding rays. The image is framed by a rectangular border.