THE REALIZATION that changes in the tongue are a consistent and reliable indication of certain deficiency states has led to many sporadic attempts to place observation of the tongue on a measurable basis. Oatway and Middleton1 used smoked paper to make tongue prints; Kruse2 utilized microscopy, and others have tried both monochromatic and color photography. Unfortunately, none of these methods have the virtue of being both simple and accurate. Moreover, none of them actually yield data which can be recorded and measured. Smoked paper prints are meritorious, except that they are negative images and the smoked paper is difficult to prepare and to transport. An added disadvantage is the need for shellacking to make permanent records. Biomicroscopy is difficult for both observer and patient. While color photography produces dramatic and striking pictures, it still does not provide an accurate record and is subject to the same optical inaccuracies