This set of fifty-six unbound and numbered pages contains two caveats copied from Edison's original manuscript by Charles Batchelor. The first, dated January 26, 1874, is for the duplex telegraph. The second, dated February 1, 1874, is for the Roman letter chemical telegraph. Several pages of the original caveat can be found in "1874. Telegraph -- General " (NS-74-001) in Unbound Notes and Drawings. In addition, there is a description in Batchelor's hand of an experiment with an automatic repeater (page 53), along with a description in Edison's hand of a chemical experiment (page 55).Blank pages not selected: 39, and all even-numbered pages.Missing pages: 1-6.
Courtesy of Thomas Edison National Historical Park.