Following James' retirement William left to run the Pittsburg operation in 1856 and the Baltimore factory was renamed to the Edwin Bennett Pottery. The first pitched battle of the American Civil War happened right in front of his business on April 19, 1861 and Edwin moved with his wife and children to Philadelphia, where in the next year or two he entered into a partnership with his friend the glassmaker William Gillinder, a notable maker of millefiori paperweights, with Bennett contributing some new pressed glass tableware designs. In 1867, the year he sold his interests to Gillinder and his sons, it was the largest glass factory within the city limits.