Oswald Kulpe and Ludwig Strumpel. Historians have found no letters written by him to colleagues while under Wundt's supervision. However, it is said that while Witmer was Wundt's assistant, they had several disagreements. One of those disputes was that Witmer desired to continue working on the study of reaction times he had previously started with Cattell, but Wundt insisted that they should study the aesthetic value of different visual forms, and other branches of psychology such as educational psychology and developmental psychology. Witmer obtained his PhD in 1892 from Wundt. Return to Pennsylvania In 1892, Witmer left Germany and returned to the University of Pennsylvania, becoming the Director of The Laboratory of Psychology. He was interested in teaching Child Psychology and taught several different courses. He also began conducting research on individual differences in sensory-perceptual variables and presented papers in experimental psychology. In 1896, he taught public school teachers at the University. During March of that year, a special case was brought before him: a 14-year-old student was having extreme difficulties learning to spell, yet was quite able and excelled in other subjects. This case offered a special challenge to Witmer, and was in line with his developing view that psychology should be of practical benefit. He soon began remedial work with the youth. Needing a workspace, Witmer established the first psychological clinic, at the University. During 1896, he presented a plan of organization for practical work in psychology to the American Psychological Association, in which he used and explained the term "Clinical Psychology" for the first time. In 1902, he started advising graduate students and published a laboratory manual. He married Emma Repplier, a prominent graduate from the Agnes Irwin School, in 1904. She was a writer who worked for the American Philosophical Society, to which both she and Witmer belonged. In 1908, he established and staffed a small private residential school near Wallingford, Pennsylvania, an institution dedicated to the care and treatment of retarded and troubled children. Later, he established a similar, but larger facility in Devon, Pennsylvania. He founded the world's first speech clinic in 1914. American Psychological Association By 1896, Witmer, G. Stanley Hall, William James and James McKeen Cattell decided to create a new association for psychology professionals, during a meeting of the American Psychological Association (APA). Witmer and other experimental colleagues proposed that the APA should accept only psychological papers, be separated from the