This unbound letterbook covers the period September 1887-October 1890. All of the letters are by Charles Batchelor and are in his hand. The correspondence relates primarily to the patents of Batchelor and Frank J. Sprague. Other letters concern the sale of stock in various Edison companies. Among the recipients are Edward H. Johnson, Brandon et Fils, and the Edison Machine Works. The book contains 68 numbered pages. Approximately 70 percent of the book has been selected. Courtesy of Thomas Edison National Historical Park.