(Oberlin College Archives)
Mary Louisa Cowles (1839-1859) and Sarah Cowles (1838-1912) were the daughters of Rev. Henry Cowles (1803-1881), teacher and founding member of Oberlin's Theological Department. Mary Lousia Cowles was a student at Oberlin preparatory school at the time of her death in 1859. A brief section of her diary can be viewed in chapter four of "Oberlin: Yesterday, Today, and Tomorrow", a third-grade textbook on the history of Oberlin.
A biography of Rev. Henry Cowles can be found in Oberlin College Archives. A brief description of the archives' inventory of Henry Cowles' papers can be found in the Women's History Guide, an inventory which includes some materials written by both Mary and Sarah. Their mother, Alice Welch Cowles, was Principal of the Ladies' Department from 1836 to 1840.