Paul Renno Heyl (1872 in Philadelphia – 22 October 1961) was an American inventor, physicist,[1] and author.
Born in Philadelphia, Heyl earned his PhD in physics in 1899 from the University of Pennsylvania.
In 1920, he was employed as a physicist at the National Bureau of Standards in Washington D.C. With Lyman J. Briggs, Heyl invented the Heyl–Briggs earth inductor compass.
This invention won for Heyl and Briggs the 1922 Magellan Medal of the American Philosophical Society.
At the NBS, Heyl worked on a redetermination of Newton's constant of gravitation using a torsion balance.