This notebook was used by Zachariah P. Halpin during March-July 1913 for experimental notes on a variety of subjects. Most of the entries pertain to the home projecting kinetoscope and to disc and cylinder phonographs. Included are tests on lenses and arc lamps for the kinetoscope, tests on various types of disc machines, and experiments on acetylene burners and miner\'s safety lamps. Also included are a few notes relating to battery tests. One entry contains a \"verbatim\"" transcription of instructions from Edison. The work on disc and cylinder machines is continued in N-13-06-13 [not selected]. The book contains 37 numbered pages, which are preceded and followed by numerous unnumbered pages; approximately 100 pages have been used. Several pages have been removed from the book."