born July 1, 1818, Lahr, Baden
died Nov. 22, 1884, Tübingen, Ger.
German physician.
He started a medical practice in 1842 and began teaching at the University of Tübingen in 1849. He discovered a way to make an exact red-blood-cell count (see blood analysis ) and invented the sphygmograph, the first instrument to produce a pulse tracing, and the hemotachometer, which monitors blood flow velocity.