Please answer a question about the following article about Boston:

Boston has been called the "Athens of America" for its literary culture, earning a reputation as "the intellectual capital of the United States." In the nineteenth century, Ralph Waldo Emerson, Henry David Thoreau, Nathaniel Hawthorne, Margaret Fuller, James Russell Lowell, and Henry Wadsworth Longfellow wrote in Boston. Some consider the Old Corner Bookstore, where these writers met and where The Atlantic Monthly was first published, to be "cradle of American literature. In 1852, the Boston Public Library was founded as the first free library in the United States. Boston's literary culture continues today thanks to the city's many universities and the Boston Book Festival.

What year was the Boston Public Library founded?
1852