The Berks County Farm and Business Directory, 1915, is now online in pdf format as part of Penn State's DIgital Bookshelf project.

Go to http://apps.libraries.psu.edu/digitalbookshelf/index.cfm, click on "Browse All Subjects," and scroll down to Berks County (Pa.) Directories.

This directory contains a list of farmers in the county as well as a business directory, and some interesting ads.

There are many other titles about Pennsylvania history at this site, too.