Harriet was first a student, in 1823, and then a teacher at Hartford Female Seminary, a school founded by her sister Catharine. At that time, Hartford Female Seminary was one of only a handful of schools that took the education of girls seriously. In 1832 Harriet moved with her family to Cincinnati, Ohio, where Rev. Dr. Lyman Beecher became President of Lane Theological Seminary. At that time, Cincinnati was considered the western frontier of the United States. In Cincinnati, in 1836, Harriet met and married Calvin E. Stowe, a professor at Lane. Six of the Stowes' seven children were born in Cincinnati. Cincinnati was just across the river from Kentucky, a slave state. It was in Cincinnati that Harriet first became aware of the horrors of slavery. Cincinnati was one of the largest cities in the country, twice the size of Hartford at that time. When Harriet and Calvin learned that their servant, Zillah, was actually a runaway slave, Calvin and Henry Ward drove her to the next station on the Underground Railroad. One night, Harriet's friend, Mr. Rankin, saw a young woman run across the river over the ice with a baby in her arms. This story moved Harriet deeply and would later become one of the most famous scenes in Uncle Tom's Cabin. In Cincinnati, Harriet became a member of the Semi-Colon Club, a local literary society in which members wrote articles which were read and discussed by other participants. Her experiences in this club sharpened her writing style. During her early married years, Harriet began to publish stories and magazine articles to supplement the family income. While she lived in Cincinnati, Harriet co-authored a book, "Primary Geography for Children". After the publication of this book Harriet received a special commendation from the bishop of Cincinnati because it conveyed a positive image of the Catholic religion. Harriet's religious tolerance was unusual for Protestants at the time. In 1850 Professor Stowe joined the faculty of his alma mater, Bowdoin College, in Brunswick, Maine. The Stowe family moved to Maine and lived in Brunswick until 1852. From 1836 to 1846 they have seven children. In 1846-7 she took the water cure at Brattleboro, Vermont, and in 1848-50 she had her last two sons, Charles and Samuel. She wrote "Uncle Tom’s Cabin,” one of the most popular novels of all time, and also the greatest abolitionist tract of it’s day and almost certainly a contributing cause to the American Civil War(1861-65). "Uncle Tom's Cabin", which appeared first in serial form in an abolitionist newspaper, The National Era, in 1851-52, was written largely in Brunswick. In 1852 the story was published in book form in two volumes. Uncle Tom's Cabin was a best seller in the United States, England, Europe, Asia, and translated into over 60 languages. She wrote "Dred" in 1856, "Oldtown Folks" in 1869 and "Palmetto Leaves" in 1873. She is one of the five seminal figures of her generation along with Emerson, Melville, Thoreau and Hawthorne. In 1852 they moved to Andover, Massachusetts, where Calvin joined the Andover Theological Seminary. In 1864 Calvin retired from Andover, and they moved to Hartford, Connecticut, where Harriet built her dream house, Oakholm. The high maintenance cost and the encroachment of factories caused her to sell it in 1870. In 1873, she moved to her last home, the brick Victorian Gothic cottage-style house on Forest Street in Hartford. In 1874, Samuel Clemens, who was the age of her twins, moved into the house next door. From 1867 to 1884, she and Calvin relocated in the winter from Connecticut to Mandarin, Florida (now a suburb of Jacksonville) to escape the pressures of her writing and to tend to personal issues. In Florida she immersed herself in programs to educate former slaves and black children. She also supervised the organization of an Episcopal church and became an early advocate of environmental protection. In 1886 Calvin died.