Because language changes, be sure to use search terms used at the time the materials were created, even if those terms are now obsolete. For example, the following historic terms will produce more results than their modern-day counterparts:
Modern Usage vs. Historic Usage comparison table
gas, service station
Afro American, Negro
From:Chronicling of America-(The Library of Congress) - http://chroniclingamerica.loc.gov/help/
A growing collection of digitized primary documents mostly on American history. You can search the collection by time period, place and broad topic. Library of Congress subject headings as used in the Earlham catalog will also work in this database.
Contains 7,247 books, 80 serials, more than fifteen manuscript collections, & court records from the from the late 15th through the to the present. Material published through partnerships with the Amistad Research Center, Oberlin College, Oxford University, & many other institutions.
This continuously growing library contains legal materials on slavery in the United States and the English-speaking world. Includes: every statute passed by every colony and state on slavery, every federal statute dealing with slavery, and all reported state and federal cases on slavery; hundreds of pamphlets and books written about slavery; every English-language legal commentary on slavery published before 1920; more than a thousand pamphlets and books on slavery from the 19th century; modern histories of slavery and a section containing all modern law review articles on the subject.
Primary documents covering the social justice efforts of Earlham, Goshen, and Manchester College, as well as their affiliated historic peace churches (Quakers, Mennonites, and Church of the Brethren) from the 1700s to the present.
Full-text page images of the newspaper, including advertisements, editorial cartoons, etc. Coverage is from 1851 up to the past three years and includes the New York Times Book Review and the New York Times Magazine.
Full text of over 1100 magazines that began publishing in the USA between 1740 and 1900, including special interest and general magazines, literary journals, children's and women's magazines, and more. Coverage extends to 1940 at the latest.