This letterbook covers the period May-August 1913. Most of the correspondence is by Edison and William H. Meadowcroft. Included are letters addressed to longtime Edison associate Samuel Insull; Oskar von Miller of the Deutsche Museum; telegraph magnate and music patron Clarence H. Mackay; and public utility executive and statesman George B. Cortelyou. Many of the letters relate to the commercial and technical development of Edison's alkaline storage battery and its use in railroad cars and electric vehicles. One item concerns the end of ore concentration experiments conducted by Edison on behalf of Henry B. Clifford, a mining engineer and promoter. There are also letters pertaining to Edison's phonograph and motion picture businesses, the choice of suitable music and singers for phonograph recordings, and the development of educational films. Additional documents concern Edison's opinions and prejudices, his charitable contributions, and his reminiscences.

The front cover is marked "T. A. E. From May 13, 1913 to Aug 6, 1913." The spine is marked with similar information, along with the number "33." The book contains 704 numbered pages and an index. Approximately 10 percent of the book has been selected.