[This introductory note to Group 7: Cell and Tube Books -- Long Tube Record Books describes all of the notebooks in Groups 5-8: Cell and Tube Books. It is followed by an enumeration of the six notebooks in Group 7. This note has no documents attached to it. For that reason, a "no Documents found" message will appear if the "List Documents" button at the bottom of the note is used. To see the notebooks described here, use the "Which Series Notes?" button to enter the Series Notes or use the "Next Text" button to move to the first item in the series.]
These forty-seven notebooks are arranged in four groups: Group 5: Battery Record Books, Nos. 1-30; Group 6: Long Tube Books, Nos. 1-7; Group 7: Long Tube Record Books, Nos. 1-6; Group 8: Battery Works Tube Books, Nos. 1-4 [not selected]. The entries, which cover the period February 1907-July 1914, are by Edison, Walter E. Holland, and other experimenters. Labels on the front covers of some of the books contain notations by Edison regarding the importance of the data contained therein.
The Battery Record Books contain logs of cell endurance tests that detail the performance of cells using various preparations of metal flake (primarily nickel, but also some cobalt). The three sets of Long Tube Books contain entries pertaining to the preparation of the tubes used in the cells. All three sets relate to the same cells, and the numbers assigned to the tubes correspond to those assigned to the cells in the endurance tests.