No dependent or incompetent relatives of the father are known. It is usual for the progenitors in the paternal branch to die between the ages of 80 and 100 years. The paternal great-grandfathers of A died aged 86 and 89 years, respectively. The paternal great-grandmothers both died at 40 years. The paternal great-great-grandmothers died at 101 and 102 years, respectively. There have been no constitutional diseases in the ancestry. A's father has but one sibling, A's paternal uncle, who is a successful dentist. He married a teacher, and has two young daughters, A's cousins. One of these, about 6 months older than A, has twice been tested by Stanford-Binet, her IQ's being 170 and, a year later, 161. At the age of 8 years, this girl had reached the fifth grade in public school. She now [[1920]] attends a special class organized for children of her age who test over 150 IQ. The other of these cousins was tested by Stanford-Binet on November 9, 1923, yielding an IQ of 129. These two girls are the only first cousins A has. A's maternal grandfather is living [[1920]] and well. He is a cloth salesman, but he has always seemed dissatisfied with this vocation. He had to go to work at an early age. The maternal grandmother is living [[1920]] and well, a competent housewife, not especially interested in intellectual pursuits. No dependent or mentally incompetent relatives of the mother are known. All are self-sustaining. There are no constitutional diseases in the maternal ancestry. It is usual for the progenitors on the maternal side to die between the ages of 60 and 70 years, but one of A's maternal great-grandmothers lived to the age of 90 years. A's mother has but one sibling, A's maternal uncle, a salesman, who is unmarried. _Father_. A's father is a large, strong man, now following the profession of organization engineer. He is a high school graduate and a graduate of Webb Academy, holding a diploma from the latter as marine engineer and marine architect. He has invented and patented a complete combustion furnace, and has designed a set of torpedoes which were used in the Japanese-Russian war. During the war of 1914-1918, he participated in the development of a fleet destroyer, and designed a boat superior to previous models for transporting nitrocellulose. He made the original layout for one of the largest steel plants in the United States. His rating on Army Alpha is 180 points. His grip is 70 kg. in the right hand and 64 kg. in the left hand (Smedley's dynamometer). He was 29 years old when A was born.