Mary Frances Leach (March 22, 1858 – 1939) was an American chemist and professor of chemistry and hygiene.
She studied at Mount Holyoke College after a stint as an elementary school teacher in Massachusetts and received her associate degree in 1880.
She then moved to Michigan and taught high school in various districts until 1891.
[1] After graduating, Leach became a chemistry professor at her alma mater, Mount Holyoke, but returned to Michigan in 1901 to become a fellow and pursue her Ph.D., which she earned in 1903.
From 1906 to her retirement in 1921, she was a professor of hygiene and chemistry at the Western College of Women.