This book is a biography of Dr. Earl H. Wood. Dr. Wood  was one of Mayo Clinic’s most prominent researchers, best known for his ground-breaking work on the G-suit during World War II.  In 1942, Earl was recruited by Mayo Clinic to conduct research on gravitational physiology on their human centrifuge. Using themselves as experimental subjects, he and fellow scientists investigated the effects of acceleration and the cause of gravitational loss of consciousness. The result was a vastly improved G-suit, which allowed Allied pilots to outmaneuver Japanese and German planes and win the air battles of World War II. Following the war, Earl continued his research, pioneering cardiac catheterization on patients with heart disease. The oximeter, which he developed to detect pulse, was enhanced to measure blood oxygen saturation levels; it is now used in every hospital and clinic in the world and is of critical importance in monitoring cardio-pulmonary status during the COVID–19 pandemic. In the 1970s, Earl and his team developed computer-based X-ray techniques, paving the way for modern CAT and MRI scanners. Dr. Wood's innovations put him in the forefront of aviation and medical science in the 20th century, and highlight one  the major contributions made by Mayo Clinic to the Allied victory in World War II