Sherman Day (February 11, 1806 – December 14, 1884) was an American politician and a civil and mining engineer in California. He designed the progenitor of the San Francisco and San Jose Railroad and served as a member of the California Senate from 1854 to 1855. He discovered, surveyed, and designed the wagon road over the Sierra Nevada in 1856 that the Pony Express used in 1860. He was one of the founders of the College of California and the son of president of Yale University, Jeremiah Day. He served as the U.S. Surveyor General of California from 1868 to 1871.
Early life and family
Sherman Day was born on February 11, 1806, in New Haven, Connecticut, to Martha (née Sherman) and Jeremiah Day. His father was a professor at Yale University. He was named after his maternal grandfather and founding father Roger Sherman. He was first cousin of Ebenezer R. Hoar He was a member of Phi Beta Kappa. After graduating, he traveled to Europe. He served as editor pro tempore of the newspaper The Pacific.
Around 1857, he became superintendent of the Almaden Quicksilver Mines and later the Mariposa Mine. In 1878, he became town engineer of Berkeley, California.