This notebook covers the period July-August 1880. Most of the entries are by Francis Upton. There are also a few entries by Edison. The material relates mainly to tests of carbon lamps. Included are a few notes and a table relating to faults that were found in the lamps, based on the experiments recorded in Notebook #103; notes and occasional drawings relating to tests of six-inch bamboo carbon lamps, along with a table of results; and a record of bets among the laboratory staff on the life of the lamps being tested. There are also notes relating to the burning of kerosene lamps in order to determine their cost; and notes on conductors, dynamos, meters, lamps, and wiring for the Menlo Park distribution system. The label on the front cover is marked "Upton" and "Lamps." The book contains 284 numbered pages.

Blank pages: 4-5.