Willem Einthoven, physiologist, physicist, and physician, developed the string galvanometer, which has proved to be one of the important instruments in the diagnosis and treatment of heart disease in modern medicine. The first description of the string galvanometer, designed for recording of heart potentials, was published early in this century. Each successive decade has witnessed increasing application of the basic design and its physical evolution beyond the initial clinical value in the diagnosis and management of maladies of the heart.
Willem Einthoven was born in 1860 at Samarang, Java, where his father was practicing medicine. After his father's death, his mother and siblings settled in Utrecht, Holland; there Willem entered the university and graduated with an MD degree in 1885. Before graduation, he engaged in limited physiological investigation, whereas after graduation he ventured into private practice for a short period. But he was destined for an academic life and, once