The H-R-R Polychromatic Plates

FOR SOME years it has been realized by those concerned with testing for anomalies of color vision that there is an urgent need in office, school, clinic, and in industrial and military examinations for a practical test which goes beyond the mere separation of those with defective color vision from those whose color vision is normal. In addition to this, it is important to be able to determine the type of defect present and its approximate extent in order to judge whether the defect constitutes a real handicap to the subject in his daily life and in the performance of his chosen work. In the H-R-R Plates we are offering such a comprehensive test. It is in the form of a book containing 21 color plates of the pseudoisochromatic type. The only auxiliary equipment is the proper illuminant. The test can be administered in three minutes or less and is