This folder contains correspondence and other documents relating to the business of the Edison Electric Light Co. of Philadelphia. Most of the letters are by William D. Marks, general manager of the company. There are also reports by Marks to the company's board of directors concerning the construction and operation of central stations and a blueprint containing a transverse section of the Philadelphia central station.

Approximately 50 percent of the documents have been selected. The following categories of documents have not been selected: routine correspondence concerning orders; duplicate copies of selected documents.