This notebook covers the period September-October 1891. All entries are by Edison. The book contains notes and drawings regarding the "blue bulb" phenomenon and the reduction of mercury vapor in incandescent lamps. There are also notes on various filament experiments, including entries, numbered 1-19, relating to the deposition of carbon and other compounds on the filaments. Edison's notations indicate that he was often assisted by an experimenter named "Joe," possibly John Joseph Force. The spine is labeled "122." The book contains 187 numbered pages.
Blank pages: 178-185.
[NA041001], Technical Note, Charles Deshler, Thomas Alva Edison, September 3rd, 1891 1891-09-03
[NA041009], Technical Note, Thomas Alva Edison, September 4th, 1891 1891-09-04
[NA041027], Technical Note, Thomas Alva Edison, Jonas Walter Aylsworth, September 5th, 1891 1891-09-05
[NA041065], Technical Note, Thomas Alva Edison, September 14th, 1891 1891-09-14
[NA041065A], Technical Note, John Joseph Force, Thomas Alva Edison, September 16th, 1891 1891-09-16
[NA041089], Technical Note, John Joseph Force, Thomas Alva Edison, October 11th, 1891 1891-10-11
[NA041101], Technical Note, John Joseph Force, Thomas Alva Edison, October 12th, 1891 1891-10-12
[NA041145], Technical Note, Thomas Alva Edison, October 13th, 1891 1891-10-13
[NA041173], Technical Note, Thomas Alva Edison, October 14th, 1891 1891-10-14