These documents, which date from January-March 1924 and September 1925, relate primarily to experiments on a new, lower-cost wax formulation for use on the recording cylinders of the Ediphone (Edison's dictating phonograph for business use). The correspondents include Nelson C. Durand, vice president of the Ediphone Division of Thomas A. Edison, Inc., and experimenters Walter N. Archer, Edward K. Cary, Charles F. (Frank) Hunter, and Joseph S. Wheelan.
All of the documents have been selected except for one item not related to Edison. Courtesy of Thomas Edison National Historical Park.