The principal object of the investigators is implied in the title of this monograph. As pointed out in the introduction, educators are not uniformly aware that deaf children may have deficiencies in reasoning and abstraction, social competence, emotional maturity, vision, and motor control. A historical survey of the conception of the interrelationship of functions for the furtherance of the biological goals of the organism serves as a preface for the entire project.
As will be surmised from the foregoing remarks, the methods and approach figure exclusively in the field of psychology. Intelligence studies, etiological classification, and controlled experimentation are carefully established. The experimental techniques include visual survey tests, drawing tests, board patterns, tachistoscopic investigation, perseveration studies, pattern reproduction, etc.
Deaf children demonstrated a marked inferiority to hearing children in the accuracy with which certain patterns were reproduced and in the capacity for adequate shifting to accommodate changing conditions. The need