In no case do we find any tests except the Binet scales which have reached a stage of practical usefulness for the diagnosis of deficiency except as supplementary aids for checking the Binet indication with children of particular ages. The emphasis has almost universally been placed on determining the central tendencies of children of different ages and not on the lower limits of the distributions. Considering mental tests apart from the Binet scale, in all the extended literature which has been brought together in books like Whipple's Manual of Mental Tests (_220_), one may seek in vain for tests which have reached the position of defining the limits of serious mental deficiency. This indicates, of course, the difficulty as well as the newness of the problem, although the quantity of work that is being done shows the great interest aroused. From all of this mass of research on mental tests one may gather much that is useful in analyzing the character of a mental defect. Many of the tests admirably aid in elaborating the subjective impression of the examiner. The failure to do this systematically has been one of the main criticisms raised against the Binet scale. This and the incorrectness of the borderline described in the published scale seem to be the main objections made by Miss Schmidt to the Binet Method. She voiced the objection of the Juvenile Psychopathic Institute in Chicago to the tests as follows: “It has been the experience of the writer, and it may be added of all others who have worked in this laboratory, where practical results are demanded, that the Binet tests cannot furnish an adequate means through which to come to conclusions for the disposition, classification, or treatment of the cases which come for diagnosis” (_179_). Dr. Merrill of the Seattle court also seems unfriendly to the Binet scale when he says: “Any system of tests by which _alone_[30] it is attempted to classify the child as being of a given mental age involves the fallacy of pseudo-exactness, and needs carefully to be avoided” (_148_). Nobody would seriously urge that real exactness of definition leads to confusion. It is just the looseness of definition of borderline with the Binet Scale which has led to most of the mistakes with it. Perhaps Dr. Merrill has not discovered that the scale works just as well when used as a graded series of tests without the designation of mental ages at all. The latter is merely a convenience. On the other hand, we should agree when he says, that “no scale of tests can give a valid measure of the child's intelligence unless supplemented by a consideration of his history,” especially if he includes in the child's history a medical diagnosis.