[The following note describes a series of notebooks and has no document records 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 records in 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 fourteen notebooks were used by Charles T. Dally and one unidentified assistant during the period 1918-1924 for experiments on the composition of disc record blanks. The research documented in these books ranges from tests of waxes, clays, and other compounds for discs to experiments on strengthening the blanks. Included are notes describing how the discs performed after being varnished, pressed, and printed in various ways and with different schedules. Many of the blanks were reinspected up to five years after they were produced, and there are brief comments on their condition by various unidentified employees. Some of the mixes tested in these books were subsequently used by William Walter Dinwiddie in his experiments (see the W. W. Dinwiddie Disc Books).
Also included are notes on "drop tests" in which the discs were dropped to test their durability. Two entries in N-19-01-08 indicate that Edison tested the surface of the blanks produced for those experiments and performed some drop tests. A few brief comments by Edison on one of the tests can be found in a loose note inserted into that book. Some early notes on disc composition experiments can also be found in N-17-00-00.6, Notebooks by Other Experimenters -- Navy and World War I Experiments -- Miscellaneous Books.
One notebook, representative of the work in the other books but more heavily annotated by Edison, has been selected. A loose item containing instructions from Edison, inserted into another book, has also been selected.