This folder contains correspondence, reports, and other documents relating to the organization and operation of Edison illuminating companies. Included are many letters and some reports from William D. Marks, supervising engineer and general manager of the Edison Electric Light Co. of Philadelphia. Some of these documents pertain to an investigation of a boiler explosion in the Philadelphia central station. There is also correspondence from F. S. Gorton, secretary-treasurer of the Chicago Edison Co., relating to environmental hazards resulting from their central station. Some of the documents may be partially illegible due to water damage.

Approximately 70 percent of the documents have been selected. The following categories of documents have not been selected: invitations to Edison to attend central station functions; letters of transmittal and acknowledgement; meeting announcements; other routine business correspondence; duplicate copies of selected documents.