[This note covers all of the notebooks in Group 4: Cement House.]
The thirty-four notebooks in this group cover the period July 1908-November 1910; one book has unrelated entries from 1937 regarding the dictation phonograph, or "Ediphone," business. The authors of the books are unidentified. Among the draftsmen who may have composed the books are J. Birkhahn, J. C. Hemphill, and H. B. Levinson. The experimenters involved in the cement house project include George E. Small and Henry J. Harms, Jr., mechanical engineers hired by Edison specifically for the project, and Robert A. Bachman, master machinist at the laboratory. The one selected notebook, N-08-07-08, contains notes, probably by Harms or Small, regarding experiments on the pouring and stabilization of the concrete. Courtesy of Thomas Edison National Historical Park.