Nicolai S. Korotkoff (1874-1920).

As a 31-year-old surgeon, with special interest in vascular disease, Korotkoff discovered the sounds of the blood pressure in 1905 while working on his doctoral thesis. After publication of the latter, he wrote nothing further about his remarkable discovery. As is often the case, others picked up on it, however, and the technique of measuring arterial blood pressure changed from one of touch to one of hearing. If not for Nicolai Korotkoff's astute observation, writes Dock, "we might still be unable to estimate diastolic pressure without trauma or use of complex devices."