This folder contains correspondence and reports relating to experiments and tests conducted on dynamos, phonoplex condensers, tubes, wires, and other equipment. There are numerous reports and letters by Henry E. Walter, an employee of the Edison Machine Works in Schenectady. Many of these items are addressed to Charles Batchelor, vice president and general manager of the company. Also included is correspondence by Batchelor pertaining to dynamo tests conducted by him.
All of the documents have been selected. Courtesy of Thomas Edison National Historical Park.