Germany's Great Meter Man
Yesterday was the 200th anniversary of the birth of German physicist Johann Christian Poggendorf. Showing a talent for creating electronic instruments early in life, Poggendorf in 1821 invented the galvanometer, a device for detecting weak electric currents. Six years later, he came up with another bedrock of modern science: the magnetometer, an instrument for measuring magnetic fields. Poggendorf greatly contributed to the rebirth of German science in the post-Napoleonic era, particularly as editor of Annalen der Physik und Chemie.