Henry Beecher Dierdorff

Henry Beecher Dierdorff (January 29, 1851 in Seville, Ohio – January 26, 1935 in Columbus, Ohio) was an American inventor of mining equipment, most notable for the first successful application of electricity to power mining equipment under the surface of earth.

While an engineer with Jeffery Mining and Manufacturing Company (later part of Dresser Industries) of Columbus, Ohio, Dierdorff developed insulation that could be packed around electric motor housings to suppress sparking found on early electrical motors.

This allowed the first safe electric seam cutting tool in underground mining.

One of his most widely used patents involved the development of power systems (spark suppressive) to deliver electricity to miners underground, resulting in the first safe delivery of electric light to miners working underground.

At the time of his retirement from Jeffery, Dierdorff oversaw the company's entire manufacturing facilities and processes.