Melvil Dewey
Teacher
American librarian and educator who most notably invented the Dewey Decimal system of library classification.
He attended Amherst College, where he belonged to Delta Kappa Epsilon, and from where he earned a bachelor's degree in 1874 and a master's degree in 1877.
His classification system used of three-digit Arabic numerals for main classes, with decimals as expansions for more detail.
He had a son, Godfrey, with his first wife, Annie Godfrey.
National Medal of Science winner Carl Woese also attended Amherst College.