[This note covers all of the notebooks in Group 3: Cement.]

The eight notebooks in this group cover the period May 1899-February 1903. They include entries by Francis R. Upton, Robert W. Rafn, and Cloyd M. Chapman; two books also contain notations by Edison. Five of these notebooks were used primarily to record a continuous series of 640 experiments pertaining to the milling of cement rock and to the desired composition of the mixed concrete, though at least one book is missing from the set. A sixth book contains a summary of some of the results obtained. Two additional books are by Chapman and contain notes on orders placed for the construction of kilns and other equipment, as well as notes on the development of bags for the storage and shipment of cement.

Entries from four notebooks have been selected. N-99-05-23 contains Edison marginalia about the milling and mixing experiments, as well as Upton's notes on the "Scheme of Tests." N-99-06-22.1 contains four pages of calculations and preliminary sketches by Edison of a cement operation, in addition to several pages of notes by Upton that summarize some of the milling and mixing tests in the preceding book. N-99-10-00 is the sixth, summary book of results, and N-02-05-24.1 contains notes by Chapman regarding orders for kilns and other equipment, possibly intended for Edison's cement plant in Stewartsville, New Jersey.