Invented by Willem Einthoven in 1903, the electrocardiograph is an
instrument which is used in the examination of people suffering from
heart disease. It indicates how
serious their illness is and maintains a check on
recovery subsequent to a
heart attack. In essence, it detects the amount of
electricity that passes through the heart
muscle as it pumps
blood through the
body.
Einthoven's successful
invention earned him a
Nobel prize in 1924, and stemmed from the discovery by two
German scientists in the mid-19th century that a frog's heart creates an electronic
current.