That is an important theorem in geometry: if two lines intersect to form adjacent congruent angles, then the lines are perpendicular. Those congruent angles would be right angâ¦les.
Williams later became chief surgeon of the Freedmenâs Hospital. Daniel Hale Williams III was born on January 18, 1856, in Hollidaysburg, Pennsylvania, to Sarah Price Williams and Daniel Hale Williams II. The couple had several children, with the elder Daniel H. Williams inheriting a barber business.
Personal Bio. Dr. Daniel Hale Williams was an African American physician who made history by performing the first successful open heart surgery operation. Daniel Hale Williams was born in 1856 in Hollidaysburg, Pennsylvania, the fifth of eight children. His father was a barber who died when Daniel was only nine.