Charles Francis Brush

Charles Francis Brush (March 17, 1849 – June 15, 1929) was an American engineer, inventor, entrepreneur, and philanthropist.

Brush was born in Euclid Township, Ohio, to Isaac Elbert Brush and Delia Williams Phillips. Isaac Brush was a distant cousin of Delia on the Phillips side. Through Delia he was a descendant of the Rev. George Phillips, who settled Watertown, Massachusetts, in 1630. Delia was also a descendant of Henry Wisner, member of the First and Second Continental Congresses during the American Revolution, as well as Thomas Cornell (settler) and the Winthrop family.

Brush was raised on a farm about 10 miles from downtown Cleveland. He had a great interest in science, particularly with Humphry Davy's experiments with the arc light; he tinkered with and built simple electrical devices such as a static electricity machine at age 12, experimenting in a workshop on his parents' farm. Brush attended Central High School in Cleveland where he built his first arc light, and graduated there with honors in 1867. His high school commencement oration was on the "Conservation of Force". He received his college undergraduate education from the University of Michigan, where he studied mining engineering, graduating in 1869 (there were no majors—as there are today—in electrical engineering). At Michigan, Brush was a member of Delta Kappa Epsilon fraternity (Omicron chapter). Brush earned his PhD at Western Reserve (now Case Western Reserve University), graduating in 1880.

In 1876 he secured the backing of the Wetting Supply Company in Cleveland to design his "dynamo" (an electrical generator) for powering arc lights. Brush began with the dynamo design of Zénobe Gramme but his final design was a marked divergence, retaining the ring armature idea that originated with Antonio Pacinotti. Brush remarked on his motivation for improving the generator in his U.S. patent 189,997: "The best forms of magneto-electric apparatus at present before the public are unnecessarily bulky, heavy, and expensive, and are more or less wasteful of mechanical power." After comparing it to the Gramme dynamo and other European entrants, the Franklin Institute of Philadelphia judged Brush's dynamo superior due to its simpler design and maintainability after completing tests in 1878.

Brush produced additional patents refining the design of his arc lights in the coming years and sold systems to several cities for public lighting, and even equipped Philadelphia's Wanamaker's Grand Depot with a system. His lights were easier to maintain, had automatic functions and burned twice as long as Yablochkov candles. His generators were reliable and automatically increased voltage with greater load while keeping current constant. By 1881, New York, Boston, Philadelphia, Baltimore, Montreal, Buffalo, San Francisco, Cleveland, and other cities had Brush arc light systems, producing public light well into the 20th century.

The San Francisco system was the first case of a utility selling electricity from a central plant to multiple customers via distribution lines. The California Electric Light Company (now PG&E) purchased two generators from Charles Brush's company in 1879 and soon opened a second plant with four additional generators. Service charges for light from sundown to midnight was US$10 per lamp per six day week. Brush's system was lighting Broadway two years before Edison's Pearl Street Station began lighting New York. By 1893 there were 1500 arc lights illuminating New York streets.

Charles F. Brush High School in Lyndhurst, Ohio is named after Brush, whose sports teams and other groups are named the "Arcs", after Brush's lamp. They wear Brown and Gold.

Charles F. Brush Preparatory High School in Dansha, Ethiopia opened in 2018, constructed by Brush alumni and the Tigray Development Association.

Metro Parks, Serving Summit County's Furnace Run Metro Park in Richfield, Ohio, received a donation of land from the Family of Charles F. Brush. The donated tract is known as Brushwood.

USS Brush (DD-745) 1943-1969 (then Taiwan's Hsiang Yang until scrapped in 1993) was named after Brush, sponsored by his great-granddaughter.

Rumford Prize of the American Academy of Arts and Sciences (1899)

Elected Member of the American Philosophical Society (1910)

Elected Member of the American Academy of Arts and Sciences (1917)

Fellow of the North British Academy of Arts

Generator (Magneto Electric Machine) 1877 U.S. patent 189,997

Arc light (automatic control of spark gap) 1878 U.S. patent 203,411

Arc light (double-carbon lamp regulation system) 1879 U.S. patent 219,208

Arc light (Automatic shut off for Electric Lights or Motors) 1880 U.S. patent 234,456

Arc light (improved regulator for the carbon arc) 1885 U.S. patent 312,184